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Posted to users@camel.apache.org by Nasim Anza <na...@googlemail.com> on 2009/05/14 11:45:34 UTC
Calling dynamically multiple http endpoints
Hi,
I would like to implement the following route with Camel 1.6 :
from("direct:endpointA")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
.to("http://xxxxxx")
.to("direct:endPointB")
from("direct:endpointB")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
.to("http://xxxxxx")
.to("direct:endPointC")
from("direct:endPointC")
.to("xquery:response.xml");
This route works fine if both URLs : http://myAddressA and
http://myAddressBare accessible and no error occurs during the
invocation.
Unfortunately, sometimes these services become unreachable and I would like
to try other URLs until getting valid answer:
If an exception happens when calling the URL http:/:myAddressA, I would like
to attempt other URLs : myAddressA1, myAddressA2, ...until getting valid
HTTP response.
The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
With java this could be simply coded like following :
try
{
call_http(myAddressA)
}
catch(Throwable th)
{
try
{
call_http(myAddressA1)
}
catch(Exception x)
{
//Call addressA2
....
}
}
I've tried the onException() mechanism and the deadLetterChannel processor
but I never get working my route.
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
On Tue, May 19, 2009 at 6:29 PM, Nasim Anza <na...@googlemail.com> wrote:
> My second webservice generates an internal error.
> I corrected the error and added the FileOverProcessor within my camel route.
> All things are working fine.
> Thank you for all answers and ideas.
Fantastic. Glad you got it sorted and that we could find a solution
for our failover requirement.
We will of course in the future improve the one we have in Camel 2.0
to allow it to have settings for master/slave etc and much.
Any feedback is much welcome.
Anyway, Nasmo welcome on the Camel rider.
>
> Nasmo.
>
> On Tue, May 19, 2009 at 11:03 AM, Claus Ibsen <cl...@gmail.com> wrote:
>
>> On Tue, May 19, 2009 at 10:52 AM, Nasim Anza <na...@googlemail.com>
>> wrote:
>> > Hi,
>> >
>> > Yes the pipeline EIP answers to my needs.
>> > I've tried to do it using the pipes and filters EIP pattern as suggested.
>> >
>> > The first block "endpointA" works and its output is the input of the
>> > endpointB block but I got the following exception when myServiceB is
>> > requested : "org.apache.commons.httpclient.NoHttpResponseException: The
>> > server localhost failed to respond"
>> Well look at the HTTP server and see why it did not reply. Maybe
>> something went wrong on this server so it could no reply.
>>
>>
>>
>> >
>> > It seems very simple but hard to get it working ,-)
>> >
>> > My route can be displayed on "http://pastebin.com/m2009204d" :
>> >
>> > from("jbi:endpoint:myClientEndPoint").to("direct:pipelinetest");
>> >
>> > from("direct:pipelinetest")
>> > .pipeline("direct:endpointA", "direct:endpointB", "direct:endpointC");
>> >
>> >
>> > from("direct:endpointA")
>> > .setHeader(HttpProducer.HTTP_URI).constant("http://localhost/myServiceA
>> ")
>> > .setHeader("SOAPAction", constant("mynamespace#OperationA"))
>> > .setHeader("Content-Type", constant("text/xml;charset=ISO-8859-1"))
>> > .to("http://localhost/myServiceA");
>> >
>> > from("direct:endpointA")
>> > .setHeader(HttpProducer.HTTP_URI).constant("http://localhost/myServiceB
>> ")
>> > .setHeader("SOAPAction", constant("mynamespace#OperationB"))
>> > .setHeader("Content-Type", constant("text/xml;charset=ISO-8859-1"))
>> > .to("http://localhost/myServiceB");
>> >
>> > from("direct:endpointC")
>> > .to("log:display output");
>> >
>> > Thanks for your help.
>> > nasmo
>> >
>> >
>> > On Mon, May 18, 2009 at 4:05 PM, Claus Ibsen <cl...@gmail.com>
>> wrote:
>> >
>> >> On Mon, May 18, 2009 at 3:56 PM, Nasim Anza <na...@googlemail.com>
>> >> wrote:
>> >> > Thanks Claus for your help.
>> >> >
>> >> > Actually the problem I got is not related to the FailOverProcessor
>> >> mechanism
>> >> > but in the global route:
>> >> > I would like that the result of a given HTTP endoint goes into
>> another
>> >> HTTP
>> >> > endpoint.
>> >> > For example the result of HTTP endpointA will be redirected to the
>> HTTP
>> >> > endpoint B.... etc
>> >> That is the pipes and filters EIP pattern:
>> >> http://camel.apache.org/pipes-and-filters.html
>> >>
>> >> So basically its like
>> >> .to("a", "b", "c");
>> >> where the output from a is input to b and output from b is input to c
>> and
>> >> so on.
>> >>
>> >> I will suggest that you try without the failover and get this
>> >> implemented so you got the "normal situation" covered.
>> >> When that is working we can take a look again how to do error handling
>> >> and failover.
>> >>
>> >>
>> >> >
>> >> > I've pasted my route and my FailOver Processor on pastbin URL :
>> >> > http://mmo.pastebin.com/m7160e173
>> >> >
>> >> > Please let me know if I have any error or mistake in the code.
>> >> >
>> >> > Note : the appliA1, appliA2, .appliX are webservices that return valid
>> >> SOAP
>> >> > XMLs
>> >> >
>> >> > Thanks a lot for any help
>> >> >
>> >> > Nasmo
>> >> >
>> >> >
>> >> > On Sat, May 16, 2009 at 4:52 PM, Claus Ibsen <cl...@gmail.com>
>> >> wrote:
>> >> >
>> >> >> Hi
>> >> >>
>> >> >> I have created an example how to do your own custom processor as
>> >> >> failover. Its based on an unit test and the code is here:
>> >> >>
>> >> >>
>> >> >>
>> >>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/issues/CustomFailveOverProcessor.java
>> >> >>
>> >> >> The code is based on Camel 2.0, but you can do the same in Camel 1.x.
>> >> >>
>> >> >>
>> >> >> On Sat, May 16, 2009 at 4:37 PM, Claus Ibsen <cl...@gmail.com>
>> >> >> wrote:
>> >> >> > Hi
>> >> >> >
>> >> >> > Sometimes its easier to read the code when there is quite a bit if
>> you
>> >> >> > paste it using http://pastebin.com/ or the likes.
>> >> >> >
>> >> >> >
>> >> >> >
>> >> >> > On Fri, May 15, 2009 at 5:44 PM, Nasim Anza <
>> nasmo2009@googlemail.com
>> >> >
>> >> >> wrote:
>> >> >> >> Thanks Claus for answers.
>> >> >> >>
>> >> >> >> My processor is working fine and it finds the URL to invoke but
>> the
>> >> >> problem
>> >> >> >> is on the last step : the next endpoint is not called with right
>> XML
>> >> >> input :
>> >> >> >>
>> >> >> >> Just to explain my actual problem :
>> >> >> >> Let's assume that my route is :
>> >> >> >>
>> >> >> >> from("direct:endpointA")
>> >> >> >> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >> >> >> .process(myFailOverProcessor("direct:endpointB")); //forward HTTP
>> >> >> response
>> >> >> >> to the direct:endpointB
>> >> >> >>
>> >> >> >> from("direct:endpointB")
>> >> >> >> .to("log:display the XML input"); //just display it to compare
>> XMLs
>> >> >> >>
>> >> >> >> The displayed XML on the "log:..." endpoint doesn't correspond to
>> the
>> >> >> http
>> >> >> >> response of "http://myAddressA"...
>> >> >> >>
>> >> >> >> Here is my Processor class :
>> >> >> >>
>> >> >> >>
>> >> >> >> public class FailOverProcessor implements Processor{
>> >> >> >>
>> >> >> >> public FailOverProcessor(String endpoint) {
>> >> >> >> this.endpoint=endpoint;
>> >> >> >> }
>> >> >> >>
>> >> >> >> public void process(Exchange exchange) throws Exception {
>> >> >> >> Exchange out = null;
>> >> >> >> int index = 0;
>> >> >> >> out = processExchange(exchange);
>> >> >> >>
>> >> >> >> while (exchange.getException() != null){
>> >> >> >>
>> >> >> >> //reset the exchange exceptiuon
>> >> >> >> exchange.setException(null);
>> >> >> >>
>> >> >> >> if (index++ < 4 ) {
>> >> >> >> System.out.println(index+" : processExchange
>> .....");
>> >> >> >>
>> >> >> >> out = processExchange(exchange);
>> >> >> >> }
>> >> >> >> }
>> >> >> >>
>> >> >> >> if(endpoint != null)
>> >> >> >> {
>> >> >> >> ProducerTemplate<Exchange> template =
>> >> >> >> exchange.getContext().createProducerTemplate();
>> >> >> >> if(out != null)
>> >> >> >> {
>> >> >> >>
>> >> >> >> Message responseOut = exchange.getOut();
>> >> >> >> int responseCode =
>> >> >> >> responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE,
>> >> Integer.class);
>> >> >> >> System.out.println("\n\n Response out \\n" +
>> responseCode
>> >> +
>> >> >> >> responseOut.getBody(String.class));
>> >> >> >>
>> >> >> >> //I've tried all the these calls but no valid response
>> >> >> >> // template.send(endpoint,
>> >> exchange.getOut().getExchange());
>> >> >> >> // template.sendBody(endpoint, exchange.getBody());
>> >> >> >> template.send(endpoint, exchange);
>> >> >> >> }
>> >> >> >> }
>> >> >> >> }
>> >> >> >>
>> >> >> >> private Exchange processExchange(Exchange exchange) {
>> >> >> >>
>> >> >> >> Exchange out = null;
>> >> >> >>
>> >> >> >> try {
>> >> >> >>
>> >> >> >> //Define the strategy to use for processing message
>> >> >> >> String uri =
>> >> >> >>
>> >> >>
>> >>
>> exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
>> >> >> >> System.out.println("Current URI ==> "+uri);
>> >> >> >>
>> >> >> >> //just for test
>> >> >> >> if(uri.equalsIgnoreCase("http://myAddressA"))
>> >> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> >> >> http://serverA/appli1");
>> >> >> >> else if(uri.equalsIgnoreCase("http://myAddressB"))
>> >> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> >> >> http://serverB/appli2");
>> >> >> >> else
>> >> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> >> >> http://serverC/error");
>> >> >> >>
>> >> >> >> ProducerTemplate<Exchange> template =
>> >> >> >> exchange.getContext().createProducerTemplate();
>> >> >> >>
>> >> >> >> out = template.send(uri, exchange);
>> >> >> >>
>> >> >> >> } catch (Throwable th) {
>> >> >> >> //Set the thrown exception
>> >> >> >> exchange.setException(th.getCause());
>> >> >> >> }
>> >> >> >>
>> >> >> >> return out;
>> >> >> >> }
>> >> >> >> }
>> >> >> >>
>> >> >> >> Thanks for your help
>> >> >> >> Nasmo
>> >> >> >>
>> >> >> >>
>> >> >> >>
>> >> >> >>
>> >> >> >> On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <
>> claus.ibsen@gmail.com>
>> >> >> wrote:
>> >> >> >>
>> >> >> >>> You need to test the exchange afterwards if there was an
>> exception.
>> >> >> >>>
>> >> >> >>> template.send(endpoint, exchange);
>> >> >> >>> if (exchange.getException() != null) {
>> >> >> >>> // ops it failed so call the next URI as fallback
>> >> >> >>> ...
>> >> >> >>> }
>> >> >> >>>
>> >> >> >>>
>> >> >> >>>
>> >> >> >>>
>> >> >> >>> >
>> >> >> >>> > Unfortunately this doesn't change anything on the SMIX console.
>> I
>> >> >> have
>> >> >> >>> the
>> >> >> >>> > same error :
>> >> >> >>> >
>> >> >> >>> > FATAL - DeadLetterChannel - Failed delivery for
>> >> >> exchangeId:
>> >> >> >>> > ID-ROME/1982-1242375956166/0-
>> >> >> >>> > Handled by the failure
>> >> >> >>> processor:sendTo(Endpoint[direct:deadLetterChannel])
>> >> >> >>> >
>> >> >> >>> > Thanks for help
>> >> >> >>> >
>> >> >> >>> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <
>> >> claus.ibsen@gmail.com
>> >> >> >
>> >> >> >>> wrote:
>> >> >> >>> >
>> >> >> >>> >> Hi
>> >> >> >>> >>
>> >> >> >>> >> You should *not* route after your custom failover processor.
>> You
>> >> >> >>> >> custom failover processor should be the end of the route (eg
>> no
>> >> more
>> >> >> >>> >> .to after your processor).
>> >> >> >>> >>
>> >> >> >>> >>
>> >> >> >>> >>
>> >> >> >>> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <
>> >> >> nasmo2009@googlemail.com>
>> >> >> >>> >> wrote:
>> >> >> >>> >> > Hi,
>> >> >> >>> >> >
>> >> >> >>> >> > I’ve tried this solution:
>> >> >> >>> >> > I started by developing a processor that loops on URIs until
>> >> >> getting a
>> >> >> >>> >> valid
>> >> >> >>> >> > answer.
>> >> >> >>> >> > The only problem is my route is interrupted at the end of
>> the
>> >> >> first
>> >> >> >>> >> > processing, so no way to pass from first block (addressA) to
>> >> next
>> >> >> >>> block
>> >> >> >>> >> > (AddressB).
>> >> >> >>> >> >
>> >> >> >>> >> > The process() method loops on all URI until getting the
>> valid
>> >> URI.
>> >> >> >>> This
>> >> >> >>> >> > works but after that I got a fatal error and the route flow
>> was
>> >> >> >>> >> interrupted.
>> >> >> >>> >> > Below the error I got on ServiceMix console:
>> >> >> >>> >> >
>> >> >> >>> >> > ----------------
>> >> >> >>> >> >
>> >> >> >>> >> > FATAL - DeadLetterChannel - Failed delivery for
>> >> >> >>> exchangeId:
>> >> >> >>> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure
>> >> processor:
>> >> >> >>> >> > sendTo(Endpoint[direct:deadLetterChannel])
>> >> >> >>> >> > 15 mai 2009 09:32:37
>> org.apache.cxf.phase.PhaseInterceptorChain
>> >> >> >>> >> doIntercept
>> >> >> >>> >> > INFO: Interceptor has thrown exception, unwinding now
>> >> >> >>> >> > org.apache.xerces.dom.TextImpl
>> >> >> >>> >> >
>> >> >> >>> >> > ----------------
>> >> >> >>> >> >
>> >> >> >>> >> > Here is my Camel route:
>> >> >> >>> >> >
>> >> >> >>> >> > * //Declare Deadletter processor*
>> >> >> >>> >> >
>> >> >> >>> >> >
>> >> >> >>> >>
>> >> >> >>>
>> >> >>
>> >>
>> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
>> >> >> >>> >> > *
>> >> >> >>> >> >
>> >> >> >>> >> > * //Declare global exception*
>> >> >> >>> >> >
>> >> >> >>> >> > *onException(Exception.class).maximumRedeliveries(5) //5 :
>> >> because
>> >> >> I
>> >> >> >>> have
>> >> >> >>> >> 5
>> >> >> >>> >> > address maximum to call*
>> >> >> >>> >> >
>> >> >> >>> >> > *final Processor myprocessor() = new Processor(Exchange
>> >> exchange)
>> >> >> >>> throws
>> >> >> >>> >> > Exception{*
>> >> >> >>> >> > **
>> >> >> >>> >> >
>> >> >> >>> >> > *ProducerTemplate<Exchange> template
>> >> >> >>> >> > exchange.getContext().createProducerTemplate();
>> >> >> >>> >> > String uri =
>> >> >> >>> >>
>> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
>> >> >> >>> >> > *
>> >> >> >>> >> >
>> >> >> >>> >> > *//This method returns the valid list depending on the
>> current
>> >> >> http
>> >> >> >>> URI*
>> >> >> >>> >> >
>> >> >> >>> >> > *List<Strig> uris = getUriList(uri);*
>> >> >> >>> >> >
>> >> >> >>> >> > *for (String uri : uris) {*
>> >> >> >>> >> >
>> >> >> >>> >> > * try {*
>> >> >> >>> >> >
>> >> >> >>> >> > * template.send(uri, exchange);*
>> >> >> >>> >> >
>> >> >> >>> >> > * } catch (Exception e) {*
>> >> >> >>> >> >
>> >> >> >>> >> > * exchange.setExceptipn(e);*
>> >> >> >>> >> >
>> >> >> >>> >> > * }*
>> >> >> >>> >> >
>> >> >> >>> >> > * if (exchange.getException() == null) {*
>> >> >> >>> >> >
>> >> >> >>> >> > * return;
>> >> >> >>> >> > }
>> >> >> >>> >> > }
>> >> >> >>> >> > }*
>> >> >> >>> >> >
>> >> >> >>> >> > * *
>> >> >> >>> >> >
>> >> >> >>> >> > *from("direct:endpointA")
>> >> >> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA
>> ")
>> >> >> >>> >> > .process(myUrlLookerProcessor())
>> >> >> >>> >> > .to("direct:endPointB")*
>> >> >> >>> >> >
>> >> >> >>> >> > *from("direct:endpointB")
>> >> >> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB
>> ")
>> >> >> >>> >> > .process(myUrlLookerProcessor())
>> >> >> >>> >> > .to("direct:endPointC")*
>> >> >> >>> >> >
>> >> >> >>> >> > *
>> >> >> >>> >> > from("direct:endPointC")
>> >> >> >>> >> > .to("xquery:response.xml");*
>> >> >> >>> >> >
>> >> >> >>> >> > *from("direct:letter")
>> >> >> >>> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
>> >> >> >>> >> >
>> >> >> >>> >> >
>> >> >> >>> >> >
>> >> >> >>> >> > Thanks in advance for help.
>> >> >> >>> >> >
>> >> >> >>> >> > Nasmo
>> >> >> >>> >> >
>> >> >> >>> >> >
>> >> >> >>> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <
>> >> >> claus.ibsen@gmail.com>
>> >> >> >>> >> wrote:
>> >> >> >>> >> >
>> >> >> >>> >> >> Hi
>> >> >> >>> >> >>
>> >> >> >>> >> >> BTW You can also always just use a Processor and implement
>> the
>> >> >> >>> >> >> failover logic yourself as pure Java with try .. catch and
>> use
>> >> >> the
>> >> >> >>> >> >> ProducerTemplate to send the exchange to the endpoint based
>> on
>> >> >> the
>> >> >> >>> >> >> URI.
>> >> >> >>> >> >>
>> >> >> >>> >> >> Something like
>> >> >> >>> >> >> ProducerTemplate template = // get it from CamelContext and
>> >> get
>> >> >> it
>> >> >> >>> once
>> >> >> >>> >> >> List<Strig> uris = ...
>> >> >> >>> >> >>
>> >> >> >>> >> >> for (String uri : uris) {
>> >> >> >>> >> >> try {
>> >> >> >>> >> >> template.send(uri, exchange);
>> >> >> >>> >> >> } catch (Exception e) {
>> >> >> >>> >> >> exchange.setExceptipn(e);
>> >> >> >>> >> >> }
>> >> >> >>> >> >> if (exchange.getException() == null) {
>> >> >> >>> >> >> return;
>> >> >> >>> >> >> }
>> >> >> >>> >> >> }
>> >> >> >>> >> >>
>> >> >> >>> >> >>
>> >> >> >>> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <
>> >> >> claus.ibsen@gmail.com>
>> >> >> >>> >> >> wrote:
>> >> >> >>> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
>> >> >> >>> nasmo2009@googlemail.com
>> >> >> >>> >> >
>> >> >> >>> >> >> wrote:
>> >> >> >>> >> >> >> Thanks Claus for your quick answer.
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >> I downloaded the source of camel 2.0 and I looked at the
>> >> >> >>> >> >> >> FailOverLoadBalancer class. I think that this could
>> answer
>> >> to
>> >> >> my
>> >> >> >>> >> >> question.
>> >> >> >>> >> >> >> I've tried to adapt the code to my requirement but I
>> have
>> >> some
>> >> >> >>> >> questions
>> >> >> >>> >> >> >> about the list of processors used in this class :
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >> 1. I don't know How to create or initialize the
>> processors
>> >> >> used
>> >> >> >>> for
>> >> >> >>> >> >> >> balancing user requests ?
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >> 3. Whait is the syntaxe (maybe something like new
>> >> >> >>> >> Processor(myHttpURL))
>> >> >> >>> >> >> > Hi
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > Yeah there is no nice DSL support for it and the
>> >> loadbalance()
>> >> >> DSL
>> >> >> >>> >> >> > does not have a nice support for custom load balancer.
>> >> >> >>> >> >> > So that is something we might need to improve in the
>> future.
>> >> I
>> >> >> have
>> >> >> >>> to
>> >> >> >>> >> >> > remember this thread.
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > So what you basically have to do is to add your custom
>> load
>> >> >> >>> balancer
>> >> >> >>> >> >> > as a processor, so use the process() DSL.
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > And your custom fail over loadbalancer can accept a list
>> of
>> >> >> >>> endpoints
>> >> >> >>> >> >> > to select among. You can wrap an endpoint to a processor
>> >> >> >>> >> >> > with the SendToProcessor.
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > Something like this
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > MyFailover my = new MyFailoverProcessor()l;
>> >> >> >>> >> >> > my.addEndpoint("foo");
>> >> >> >>> >> >> > my.addEndpoint("bar");
>> >> >> >>> >> >> >
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > And in the route DSL you just route to your processor
>> >> >> >>> >> >> > from(x).process(my);
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > And in the addEndpoint method you add the endpoint by
>> >> wrapping
>> >> >> it
>> >> >> >>> with
>> >> >> >>> >> >> > a SendToProcessor so you can add it to the
>> >> LoadBalancerSupport
>> >> >> >>> class.
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > See how it goes and ask again tomorrow when I am back in
>> the
>> >> >> office
>> >> >> >>> >> >> > and can better work. As I sit now with the laptop in the
>> >> living
>> >> >> >>> room.
>> >> >> >>> >> >> >
>> >> >> >>> >> >> >
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >> Thanks for help
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
>> >> >> >>> claus.ibsen@gmail.com
>> >> >> >>> >> >
>> >> >> >>> >> >> wrote:
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >>> Hi
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>> There are load balancers with Camel
>> >> >> >>> >> >> >>> http://camel.apache.org/load-balancer.html
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>> And there is a failover load balancer as well that can
>> do
>> >> a
>> >> >> >>> simple
>> >> >> >>> >> try
>> >> >> >>> >> >> >>> the next endpoint until success kinda style.
>> >> >> >>> >> >> >>> Its a bit primitive at the moment and we would like to
>> >> >> improve
>> >> >> >>> that
>> >> >> >>> >> in
>> >> >> >>> >> >> >>> the future.
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>> But it allows you to implement your own load balancer
>> and
>> >> do
>> >> >> your
>> >> >> >>> >> >> >>> strategy how you like it.
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>> Any feedback for features that could be needed for a
>> more
>> >> >> >>> advanced
>> >> >> >>> >> >> >>> failover loadbalancer is much welcome.
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x.
>> But
>> >> >> you
>> >> >> >>> can
>> >> >> >>> >> >> >>> check the source code for 2.0 and create your own kinda
>> to
>> >> >> use in
>> >> >> >>> >> 1.x.
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >>
>> >> >> >>> >>
>> >> >> >>>
>> >> >>
>> >>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
>> >> >> >>> >> nasmo2009@googlemail.com
>> >> >> >>> >> >> >
>> >> >> >>> >> >> >>> wrote:
>> >> >> >>> >> >> >>> > Hi,
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > I would like to implement the following route with
>> Camel
>> >> >> 1.6 :
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > from("direct:endpointA")
>> >> >> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
>> >> >> http://myAddressA")
>> >> >> >>> >> >> >>> > .to("http://xxxxxx")
>> >> >> >>> >> >> >>> > .to("direct:endPointB")
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > from("direct:endpointB")
>> >> >> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
>> >> >> http://myAddressB")
>> >> >> >>> >> >> >>> > .to("http://xxxxxx")
>> >> >> >>> >> >> >>> > .to("direct:endPointC")
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > from("direct:endPointC")
>> >> >> >>> >> >> >>> > .to("xquery:response.xml");
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > This route works fine if both URLs :
>> http://myAddressAand
>> >> >> >>> >> >> >>> > http://myAddressBare accessible and no error occurs
>> >> during
>> >> >> the
>> >> >> >>> >> >> >>> > invocation.
>> >> >> >>> >> >> >>> > Unfortunately, sometimes these services become
>> >> unreachable
>> >> >> and
>> >> >> >>> I
>> >> >> >>> >> >> would
>> >> >> >>> >> >> >>> like
>> >> >> >>> >> >> >>> > to try other URLs until getting valid answer:
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > If an exception happens when calling the URL
>> >> >> http:/:myAddressA,
>> >> >> >>> I
>> >> >> >>> >> >> would
>> >> >> >>> >> >> >>> like
>> >> >> >>> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2,
>> >> ...until
>> >> >> >>> getting
>> >> >> >>> >> >> valid
>> >> >> >>> >> >> >>> > HTTP response.
>> >> >> >>> >> >> >>> > The same thing with myAddressB ==> myAddressB1,
>> >> >> myAddressB2,
>> >> >> >>> ...
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > With java this could be simply coded like following :
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > try
>> >> >> >>> >> >> >>> > {
>> >> >> >>> >> >> >>> > call_http(myAddressA)
>> >> >> >>> >> >> >>> > }
>> >> >> >>> >> >> >>> > catch(Throwable th)
>> >> >> >>> >> >> >>> > {
>> >> >> >>> >> >> >>> > try
>> >> >> >>> >> >> >>> > {
>> >> >> >>> >> >> >>> > call_http(myAddressA1)
>> >> >> >>> >> >> >>> > }
>> >> >> >>> >> >> >>> > catch(Exception x)
>> >> >> >>> >> >> >>> > {
>> >> >> >>> >> >> >>> > //Call addressA2
>> >> >> >>> >> >> >>> > ....
>> >> >> >>> >> >> >>> > }
>> >> >> >>> >> >> >>> > }
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>> > I've tried the onException() mechanism and the
>> >> >> >>> deadLetterChannel
>> >> >> >>> >> >> >>> processor
>> >> >> >>> >> >> >>> > but I never get working my route.
>> >> >> >>> >> >> >>> >
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>> --
>> >> >> >>> >> >> >>> Claus Ibsen
>> >> >> >>> >> >> >>> Apache Camel Committer
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>> Open Source Integration: http://fusesource.com
>> >> >> >>> >> >> >>> Blog: http://davsclaus.blogspot.com/
>> >> >> >>> >> >> >>> Twitter: http://twitter.com/davsclaus
>> >> >> >>> >> >> >>>
>> >> >> >>> >> >> >>
>> >> >> >>> >> >> >
>> >> >> >>> >> >> >
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > --
>> >> >> >>> >> >> > Claus Ibsen
>> >> >> >>> >> >> > Apache Camel Committer
>> >> >> >>> >> >> >
>> >> >> >>> >> >> > Open Source Integration: http://fusesource.com
>> >> >> >>> >> >> > Blog: http://davsclaus.blogspot.com/
>> >> >> >>> >> >> > Twitter: http://twitter.com/davsclaus
>> >> >> >>> >> >> >
>> >> >> >>> >> >>
>> >> >> >>> >> >>
>> >> >> >>> >> >>
>> >> >> >>> >> >> --
>> >> >> >>> >> >> Claus Ibsen
>> >> >> >>> >> >> Apache Camel Committer
>> >> >> >>> >> >>
>> >> >> >>> >> >> Open Source Integration: http://fusesource.com
>> >> >> >>> >> >> Blog: http://davsclaus.blogspot.com/
>> >> >> >>> >> >> Twitter: http://twitter.com/davsclaus
>> >> >> >>> >> >>
>> >> >> >>> >> >
>> >> >> >>> >>
>> >> >> >>> >>
>> >> >> >>> >>
>> >> >> >>> >> --
>> >> >> >>> >> Claus Ibsen
>> >> >> >>> >> Apache Camel Committer
>> >> >> >>> >>
>> >> >> >>> >> Open Source Integration: http://fusesource.com
>> >> >> >>> >> Blog: http://davsclaus.blogspot.com/
>> >> >> >>> >> Twitter: http://twitter.com/davsclaus
>> >> >> >>> >>
>> >> >> >>> >
>> >> >> >>>
>> >> >> >>>
>> >> >> >>>
>> >> >> >>> --
>> >> >> >>> Claus Ibsen
>> >> >> >>> Apache Camel Committer
>> >> >> >>>
>> >> >> >>> Open Source Integration: http://fusesource.com
>> >> >> >>> Blog: http://davsclaus.blogspot.com/
>> >> >> >>> Twitter: http://twitter.com/davsclaus
>> >> >> >>>
>> >> >> >>
>> >> >> >
>> >> >> >
>> >> >> >
>> >> >> > --
>> >> >> > Claus Ibsen
>> >> >> > Apache Camel Committer
>> >> >> >
>> >> >> > Open Source Integration: http://fusesource.com
>> >> >> > Blog: http://davsclaus.blogspot.com/
>> >> >> > Twitter: http://twitter.com/davsclaus
>> >> >> >
>> >> >>
>> >> >>
>> >> >>
>> >> >> --
>> >> >> Claus Ibsen
>> >> >> Apache Camel Committer
>> >> >>
>> >> >> Open Source Integration: http://fusesource.com
>> >> >> Blog: http://davsclaus.blogspot.com/
>> >> >> Twitter: http://twitter.com/davsclaus
>> >> >>
>> >> >
>> >>
>> >>
>> >>
>> >> --
>> >> Claus Ibsen
>> >> Apache Camel Committer
>> >>
>> >> Open Source Integration: http://fusesource.com
>> >> Blog: http://davsclaus.blogspot.com/
>> >> Twitter: http://twitter.com/davsclaus
>> >>
>> >
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Nasim Anza <na...@googlemail.com>.
My second webservice generates an internal error.
I corrected the error and added the FileOverProcessor within my camel route.
All things are working fine.
Thank you for all answers and ideas.
Nasmo.
On Tue, May 19, 2009 at 11:03 AM, Claus Ibsen <cl...@gmail.com> wrote:
> On Tue, May 19, 2009 at 10:52 AM, Nasim Anza <na...@googlemail.com>
> wrote:
> > Hi,
> >
> > Yes the pipeline EIP answers to my needs.
> > I've tried to do it using the pipes and filters EIP pattern as suggested.
> >
> > The first block "endpointA" works and its output is the input of the
> > endpointB block but I got the following exception when myServiceB is
> > requested : "org.apache.commons.httpclient.NoHttpResponseException: The
> > server localhost failed to respond"
> Well look at the HTTP server and see why it did not reply. Maybe
> something went wrong on this server so it could no reply.
>
>
>
> >
> > It seems very simple but hard to get it working ,-)
> >
> > My route can be displayed on "http://pastebin.com/m2009204d" :
> >
> > from("jbi:endpoint:myClientEndPoint").to("direct:pipelinetest");
> >
> > from("direct:pipelinetest")
> > .pipeline("direct:endpointA", "direct:endpointB", "direct:endpointC");
> >
> >
> > from("direct:endpointA")
> > .setHeader(HttpProducer.HTTP_URI).constant("http://localhost/myServiceA
> ")
> > .setHeader("SOAPAction", constant("mynamespace#OperationA"))
> > .setHeader("Content-Type", constant("text/xml;charset=ISO-8859-1"))
> > .to("http://localhost/myServiceA");
> >
> > from("direct:endpointA")
> > .setHeader(HttpProducer.HTTP_URI).constant("http://localhost/myServiceB
> ")
> > .setHeader("SOAPAction", constant("mynamespace#OperationB"))
> > .setHeader("Content-Type", constant("text/xml;charset=ISO-8859-1"))
> > .to("http://localhost/myServiceB");
> >
> > from("direct:endpointC")
> > .to("log:display output");
> >
> > Thanks for your help.
> > nasmo
> >
> >
> > On Mon, May 18, 2009 at 4:05 PM, Claus Ibsen <cl...@gmail.com>
> wrote:
> >
> >> On Mon, May 18, 2009 at 3:56 PM, Nasim Anza <na...@googlemail.com>
> >> wrote:
> >> > Thanks Claus for your help.
> >> >
> >> > Actually the problem I got is not related to the FailOverProcessor
> >> mechanism
> >> > but in the global route:
> >> > I would like that the result of a given HTTP endoint goes into
> another
> >> HTTP
> >> > endpoint.
> >> > For example the result of HTTP endpointA will be redirected to the
> HTTP
> >> > endpoint B.... etc
> >> That is the pipes and filters EIP pattern:
> >> http://camel.apache.org/pipes-and-filters.html
> >>
> >> So basically its like
> >> .to("a", "b", "c");
> >> where the output from a is input to b and output from b is input to c
> and
> >> so on.
> >>
> >> I will suggest that you try without the failover and get this
> >> implemented so you got the "normal situation" covered.
> >> When that is working we can take a look again how to do error handling
> >> and failover.
> >>
> >>
> >> >
> >> > I've pasted my route and my FailOver Processor on pastbin URL :
> >> > http://mmo.pastebin.com/m7160e173
> >> >
> >> > Please let me know if I have any error or mistake in the code.
> >> >
> >> > Note : the appliA1, appliA2, .appliX are webservices that return valid
> >> SOAP
> >> > XMLs
> >> >
> >> > Thanks a lot for any help
> >> >
> >> > Nasmo
> >> >
> >> >
> >> > On Sat, May 16, 2009 at 4:52 PM, Claus Ibsen <cl...@gmail.com>
> >> wrote:
> >> >
> >> >> Hi
> >> >>
> >> >> I have created an example how to do your own custom processor as
> >> >> failover. Its based on an unit test and the code is here:
> >> >>
> >> >>
> >> >>
> >>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/issues/CustomFailveOverProcessor.java
> >> >>
> >> >> The code is based on Camel 2.0, but you can do the same in Camel 1.x.
> >> >>
> >> >>
> >> >> On Sat, May 16, 2009 at 4:37 PM, Claus Ibsen <cl...@gmail.com>
> >> >> wrote:
> >> >> > Hi
> >> >> >
> >> >> > Sometimes its easier to read the code when there is quite a bit if
> you
> >> >> > paste it using http://pastebin.com/ or the likes.
> >> >> >
> >> >> >
> >> >> >
> >> >> > On Fri, May 15, 2009 at 5:44 PM, Nasim Anza <
> nasmo2009@googlemail.com
> >> >
> >> >> wrote:
> >> >> >> Thanks Claus for answers.
> >> >> >>
> >> >> >> My processor is working fine and it finds the URL to invoke but
> the
> >> >> problem
> >> >> >> is on the last step : the next endpoint is not called with right
> XML
> >> >> input :
> >> >> >>
> >> >> >> Just to explain my actual problem :
> >> >> >> Let's assume that my route is :
> >> >> >>
> >> >> >> from("direct:endpointA")
> >> >> >> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >> >> >> .process(myFailOverProcessor("direct:endpointB")); //forward HTTP
> >> >> response
> >> >> >> to the direct:endpointB
> >> >> >>
> >> >> >> from("direct:endpointB")
> >> >> >> .to("log:display the XML input"); //just display it to compare
> XMLs
> >> >> >>
> >> >> >> The displayed XML on the "log:..." endpoint doesn't correspond to
> the
> >> >> http
> >> >> >> response of "http://myAddressA"...
> >> >> >>
> >> >> >> Here is my Processor class :
> >> >> >>
> >> >> >>
> >> >> >> public class FailOverProcessor implements Processor{
> >> >> >>
> >> >> >> public FailOverProcessor(String endpoint) {
> >> >> >> this.endpoint=endpoint;
> >> >> >> }
> >> >> >>
> >> >> >> public void process(Exchange exchange) throws Exception {
> >> >> >> Exchange out = null;
> >> >> >> int index = 0;
> >> >> >> out = processExchange(exchange);
> >> >> >>
> >> >> >> while (exchange.getException() != null){
> >> >> >>
> >> >> >> //reset the exchange exceptiuon
> >> >> >> exchange.setException(null);
> >> >> >>
> >> >> >> if (index++ < 4 ) {
> >> >> >> System.out.println(index+" : processExchange
> .....");
> >> >> >>
> >> >> >> out = processExchange(exchange);
> >> >> >> }
> >> >> >> }
> >> >> >>
> >> >> >> if(endpoint != null)
> >> >> >> {
> >> >> >> ProducerTemplate<Exchange> template =
> >> >> >> exchange.getContext().createProducerTemplate();
> >> >> >> if(out != null)
> >> >> >> {
> >> >> >>
> >> >> >> Message responseOut = exchange.getOut();
> >> >> >> int responseCode =
> >> >> >> responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE,
> >> Integer.class);
> >> >> >> System.out.println("\n\n Response out \\n" +
> responseCode
> >> +
> >> >> >> responseOut.getBody(String.class));
> >> >> >>
> >> >> >> //I've tried all the these calls but no valid response
> >> >> >> // template.send(endpoint,
> >> exchange.getOut().getExchange());
> >> >> >> // template.sendBody(endpoint, exchange.getBody());
> >> >> >> template.send(endpoint, exchange);
> >> >> >> }
> >> >> >> }
> >> >> >> }
> >> >> >>
> >> >> >> private Exchange processExchange(Exchange exchange) {
> >> >> >>
> >> >> >> Exchange out = null;
> >> >> >>
> >> >> >> try {
> >> >> >>
> >> >> >> //Define the strategy to use for processing message
> >> >> >> String uri =
> >> >> >>
> >> >>
> >>
> exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
> >> >> >> System.out.println("Current URI ==> "+uri);
> >> >> >>
> >> >> >> //just for test
> >> >> >> if(uri.equalsIgnoreCase("http://myAddressA"))
> >> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> >> >> http://serverA/appli1");
> >> >> >> else if(uri.equalsIgnoreCase("http://myAddressB"))
> >> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> >> >> http://serverB/appli2");
> >> >> >> else
> >> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> >> >> http://serverC/error");
> >> >> >>
> >> >> >> ProducerTemplate<Exchange> template =
> >> >> >> exchange.getContext().createProducerTemplate();
> >> >> >>
> >> >> >> out = template.send(uri, exchange);
> >> >> >>
> >> >> >> } catch (Throwable th) {
> >> >> >> //Set the thrown exception
> >> >> >> exchange.setException(th.getCause());
> >> >> >> }
> >> >> >>
> >> >> >> return out;
> >> >> >> }
> >> >> >> }
> >> >> >>
> >> >> >> Thanks for your help
> >> >> >> Nasmo
> >> >> >>
> >> >> >>
> >> >> >>
> >> >> >>
> >> >> >> On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <
> claus.ibsen@gmail.com>
> >> >> wrote:
> >> >> >>
> >> >> >>> You need to test the exchange afterwards if there was an
> exception.
> >> >> >>>
> >> >> >>> template.send(endpoint, exchange);
> >> >> >>> if (exchange.getException() != null) {
> >> >> >>> // ops it failed so call the next URI as fallback
> >> >> >>> ...
> >> >> >>> }
> >> >> >>>
> >> >> >>>
> >> >> >>>
> >> >> >>>
> >> >> >>> >
> >> >> >>> > Unfortunately this doesn't change anything on the SMIX console.
> I
> >> >> have
> >> >> >>> the
> >> >> >>> > same error :
> >> >> >>> >
> >> >> >>> > FATAL - DeadLetterChannel - Failed delivery for
> >> >> exchangeId:
> >> >> >>> > ID-ROME/1982-1242375956166/0-
> >> >> >>> > Handled by the failure
> >> >> >>> processor:sendTo(Endpoint[direct:deadLetterChannel])
> >> >> >>> >
> >> >> >>> > Thanks for help
> >> >> >>> >
> >> >> >>> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <
> >> claus.ibsen@gmail.com
> >> >> >
> >> >> >>> wrote:
> >> >> >>> >
> >> >> >>> >> Hi
> >> >> >>> >>
> >> >> >>> >> You should *not* route after your custom failover processor.
> You
> >> >> >>> >> custom failover processor should be the end of the route (eg
> no
> >> more
> >> >> >>> >> .to after your processor).
> >> >> >>> >>
> >> >> >>> >>
> >> >> >>> >>
> >> >> >>> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <
> >> >> nasmo2009@googlemail.com>
> >> >> >>> >> wrote:
> >> >> >>> >> > Hi,
> >> >> >>> >> >
> >> >> >>> >> > I’ve tried this solution:
> >> >> >>> >> > I started by developing a processor that loops on URIs until
> >> >> getting a
> >> >> >>> >> valid
> >> >> >>> >> > answer.
> >> >> >>> >> > The only problem is my route is interrupted at the end of
> the
> >> >> first
> >> >> >>> >> > processing, so no way to pass from first block (addressA) to
> >> next
> >> >> >>> block
> >> >> >>> >> > (AddressB).
> >> >> >>> >> >
> >> >> >>> >> > The process() method loops on all URI until getting the
> valid
> >> URI.
> >> >> >>> This
> >> >> >>> >> > works but after that I got a fatal error and the route flow
> was
> >> >> >>> >> interrupted.
> >> >> >>> >> > Below the error I got on ServiceMix console:
> >> >> >>> >> >
> >> >> >>> >> > ----------------
> >> >> >>> >> >
> >> >> >>> >> > FATAL - DeadLetterChannel - Failed delivery for
> >> >> >>> exchangeId:
> >> >> >>> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure
> >> processor:
> >> >> >>> >> > sendTo(Endpoint[direct:deadLetterChannel])
> >> >> >>> >> > 15 mai 2009 09:32:37
> org.apache.cxf.phase.PhaseInterceptorChain
> >> >> >>> >> doIntercept
> >> >> >>> >> > INFO: Interceptor has thrown exception, unwinding now
> >> >> >>> >> > org.apache.xerces.dom.TextImpl
> >> >> >>> >> >
> >> >> >>> >> > ----------------
> >> >> >>> >> >
> >> >> >>> >> > Here is my Camel route:
> >> >> >>> >> >
> >> >> >>> >> > * //Declare Deadletter processor*
> >> >> >>> >> >
> >> >> >>> >> >
> >> >> >>> >>
> >> >> >>>
> >> >>
> >>
> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
> >> >> >>> >> > *
> >> >> >>> >> >
> >> >> >>> >> > * //Declare global exception*
> >> >> >>> >> >
> >> >> >>> >> > *onException(Exception.class).maximumRedeliveries(5) //5 :
> >> because
> >> >> I
> >> >> >>> have
> >> >> >>> >> 5
> >> >> >>> >> > address maximum to call*
> >> >> >>> >> >
> >> >> >>> >> > *final Processor myprocessor() = new Processor(Exchange
> >> exchange)
> >> >> >>> throws
> >> >> >>> >> > Exception{*
> >> >> >>> >> > **
> >> >> >>> >> >
> >> >> >>> >> > *ProducerTemplate<Exchange> template
> >> >> >>> >> > exchange.getContext().createProducerTemplate();
> >> >> >>> >> > String uri =
> >> >> >>> >>
> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
> >> >> >>> >> > *
> >> >> >>> >> >
> >> >> >>> >> > *//This method returns the valid list depending on the
> current
> >> >> http
> >> >> >>> URI*
> >> >> >>> >> >
> >> >> >>> >> > *List<Strig> uris = getUriList(uri);*
> >> >> >>> >> >
> >> >> >>> >> > *for (String uri : uris) {*
> >> >> >>> >> >
> >> >> >>> >> > * try {*
> >> >> >>> >> >
> >> >> >>> >> > * template.send(uri, exchange);*
> >> >> >>> >> >
> >> >> >>> >> > * } catch (Exception e) {*
> >> >> >>> >> >
> >> >> >>> >> > * exchange.setExceptipn(e);*
> >> >> >>> >> >
> >> >> >>> >> > * }*
> >> >> >>> >> >
> >> >> >>> >> > * if (exchange.getException() == null) {*
> >> >> >>> >> >
> >> >> >>> >> > * return;
> >> >> >>> >> > }
> >> >> >>> >> > }
> >> >> >>> >> > }*
> >> >> >>> >> >
> >> >> >>> >> > * *
> >> >> >>> >> >
> >> >> >>> >> > *from("direct:endpointA")
> >> >> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA
> ")
> >> >> >>> >> > .process(myUrlLookerProcessor())
> >> >> >>> >> > .to("direct:endPointB")*
> >> >> >>> >> >
> >> >> >>> >> > *from("direct:endpointB")
> >> >> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB
> ")
> >> >> >>> >> > .process(myUrlLookerProcessor())
> >> >> >>> >> > .to("direct:endPointC")*
> >> >> >>> >> >
> >> >> >>> >> > *
> >> >> >>> >> > from("direct:endPointC")
> >> >> >>> >> > .to("xquery:response.xml");*
> >> >> >>> >> >
> >> >> >>> >> > *from("direct:letter")
> >> >> >>> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
> >> >> >>> >> >
> >> >> >>> >> >
> >> >> >>> >> >
> >> >> >>> >> > Thanks in advance for help.
> >> >> >>> >> >
> >> >> >>> >> > Nasmo
> >> >> >>> >> >
> >> >> >>> >> >
> >> >> >>> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <
> >> >> claus.ibsen@gmail.com>
> >> >> >>> >> wrote:
> >> >> >>> >> >
> >> >> >>> >> >> Hi
> >> >> >>> >> >>
> >> >> >>> >> >> BTW You can also always just use a Processor and implement
> the
> >> >> >>> >> >> failover logic yourself as pure Java with try .. catch and
> use
> >> >> the
> >> >> >>> >> >> ProducerTemplate to send the exchange to the endpoint based
> on
> >> >> the
> >> >> >>> >> >> URI.
> >> >> >>> >> >>
> >> >> >>> >> >> Something like
> >> >> >>> >> >> ProducerTemplate template = // get it from CamelContext and
> >> get
> >> >> it
> >> >> >>> once
> >> >> >>> >> >> List<Strig> uris = ...
> >> >> >>> >> >>
> >> >> >>> >> >> for (String uri : uris) {
> >> >> >>> >> >> try {
> >> >> >>> >> >> template.send(uri, exchange);
> >> >> >>> >> >> } catch (Exception e) {
> >> >> >>> >> >> exchange.setExceptipn(e);
> >> >> >>> >> >> }
> >> >> >>> >> >> if (exchange.getException() == null) {
> >> >> >>> >> >> return;
> >> >> >>> >> >> }
> >> >> >>> >> >> }
> >> >> >>> >> >>
> >> >> >>> >> >>
> >> >> >>> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <
> >> >> claus.ibsen@gmail.com>
> >> >> >>> >> >> wrote:
> >> >> >>> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
> >> >> >>> nasmo2009@googlemail.com
> >> >> >>> >> >
> >> >> >>> >> >> wrote:
> >> >> >>> >> >> >> Thanks Claus for your quick answer.
> >> >> >>> >> >> >>
> >> >> >>> >> >> >> I downloaded the source of camel 2.0 and I looked at the
> >> >> >>> >> >> >> FailOverLoadBalancer class. I think that this could
> answer
> >> to
> >> >> my
> >> >> >>> >> >> question.
> >> >> >>> >> >> >> I've tried to adapt the code to my requirement but I
> have
> >> some
> >> >> >>> >> questions
> >> >> >>> >> >> >> about the list of processors used in this class :
> >> >> >>> >> >> >>
> >> >> >>> >> >> >> 1. I don't know How to create or initialize the
> processors
> >> >> used
> >> >> >>> for
> >> >> >>> >> >> >> balancing user requests ?
> >> >> >>> >> >> >>
> >> >> >>> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
> >> >> >>> >> >> >>
> >> >> >>> >> >> >> 3. Whait is the syntaxe (maybe something like new
> >> >> >>> >> Processor(myHttpURL))
> >> >> >>> >> >> > Hi
> >> >> >>> >> >> >
> >> >> >>> >> >> > Yeah there is no nice DSL support for it and the
> >> loadbalance()
> >> >> DSL
> >> >> >>> >> >> > does not have a nice support for custom load balancer.
> >> >> >>> >> >> > So that is something we might need to improve in the
> future.
> >> I
> >> >> have
> >> >> >>> to
> >> >> >>> >> >> > remember this thread.
> >> >> >>> >> >> >
> >> >> >>> >> >> > So what you basically have to do is to add your custom
> load
> >> >> >>> balancer
> >> >> >>> >> >> > as a processor, so use the process() DSL.
> >> >> >>> >> >> >
> >> >> >>> >> >> > And your custom fail over loadbalancer can accept a list
> of
> >> >> >>> endpoints
> >> >> >>> >> >> > to select among. You can wrap an endpoint to a processor
> >> >> >>> >> >> > with the SendToProcessor.
> >> >> >>> >> >> >
> >> >> >>> >> >> > Something like this
> >> >> >>> >> >> >
> >> >> >>> >> >> > MyFailover my = new MyFailoverProcessor()l;
> >> >> >>> >> >> > my.addEndpoint("foo");
> >> >> >>> >> >> > my.addEndpoint("bar");
> >> >> >>> >> >> >
> >> >> >>> >> >> >
> >> >> >>> >> >> > And in the route DSL you just route to your processor
> >> >> >>> >> >> > from(x).process(my);
> >> >> >>> >> >> >
> >> >> >>> >> >> > And in the addEndpoint method you add the endpoint by
> >> wrapping
> >> >> it
> >> >> >>> with
> >> >> >>> >> >> > a SendToProcessor so you can add it to the
> >> LoadBalancerSupport
> >> >> >>> class.
> >> >> >>> >> >> >
> >> >> >>> >> >> > See how it goes and ask again tomorrow when I am back in
> the
> >> >> office
> >> >> >>> >> >> > and can better work. As I sit now with the laptop in the
> >> living
> >> >> >>> room.
> >> >> >>> >> >> >
> >> >> >>> >> >> >
> >> >> >>> >> >> >>
> >> >> >>> >> >> >> Thanks for help
> >> >> >>> >> >> >>
> >> >> >>> >> >> >>
> >> >> >>> >> >> >>
> >> >> >>> >> >> >>
> >> >> >>> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
> >> >> >>> claus.ibsen@gmail.com
> >> >> >>> >> >
> >> >> >>> >> >> wrote:
> >> >> >>> >> >> >>
> >> >> >>> >> >> >>> Hi
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>> There are load balancers with Camel
> >> >> >>> >> >> >>> http://camel.apache.org/load-balancer.html
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>> And there is a failover load balancer as well that can
> do
> >> a
> >> >> >>> simple
> >> >> >>> >> try
> >> >> >>> >> >> >>> the next endpoint until success kinda style.
> >> >> >>> >> >> >>> Its a bit primitive at the moment and we would like to
> >> >> improve
> >> >> >>> that
> >> >> >>> >> in
> >> >> >>> >> >> >>> the future.
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>> But it allows you to implement your own load balancer
> and
> >> do
> >> >> your
> >> >> >>> >> >> >>> strategy how you like it.
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>> Any feedback for features that could be needed for a
> more
> >> >> >>> advanced
> >> >> >>> >> >> >>> failover loadbalancer is much welcome.
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x.
> But
> >> >> you
> >> >> >>> can
> >> >> >>> >> >> >>> check the source code for 2.0 and create your own kinda
> to
> >> >> use in
> >> >> >>> >> 1.x.
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>>
> >> >> >>> >> >>
> >> >> >>> >>
> >> >> >>>
> >> >>
> >>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
> >> >> >>> >> nasmo2009@googlemail.com
> >> >> >>> >> >> >
> >> >> >>> >> >> >>> wrote:
> >> >> >>> >> >> >>> > Hi,
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > I would like to implement the following route with
> Camel
> >> >> 1.6 :
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > from("direct:endpointA")
> >> >> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
> >> >> http://myAddressA")
> >> >> >>> >> >> >>> > .to("http://xxxxxx")
> >> >> >>> >> >> >>> > .to("direct:endPointB")
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > from("direct:endpointB")
> >> >> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
> >> >> http://myAddressB")
> >> >> >>> >> >> >>> > .to("http://xxxxxx")
> >> >> >>> >> >> >>> > .to("direct:endPointC")
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > from("direct:endPointC")
> >> >> >>> >> >> >>> > .to("xquery:response.xml");
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > This route works fine if both URLs :
> http://myAddressAand
> >> >> >>> >> >> >>> > http://myAddressBare accessible and no error occurs
> >> during
> >> >> the
> >> >> >>> >> >> >>> > invocation.
> >> >> >>> >> >> >>> > Unfortunately, sometimes these services become
> >> unreachable
> >> >> and
> >> >> >>> I
> >> >> >>> >> >> would
> >> >> >>> >> >> >>> like
> >> >> >>> >> >> >>> > to try other URLs until getting valid answer:
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > If an exception happens when calling the URL
> >> >> http:/:myAddressA,
> >> >> >>> I
> >> >> >>> >> >> would
> >> >> >>> >> >> >>> like
> >> >> >>> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2,
> >> ...until
> >> >> >>> getting
> >> >> >>> >> >> valid
> >> >> >>> >> >> >>> > HTTP response.
> >> >> >>> >> >> >>> > The same thing with myAddressB ==> myAddressB1,
> >> >> myAddressB2,
> >> >> >>> ...
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > With java this could be simply coded like following :
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > try
> >> >> >>> >> >> >>> > {
> >> >> >>> >> >> >>> > call_http(myAddressA)
> >> >> >>> >> >> >>> > }
> >> >> >>> >> >> >>> > catch(Throwable th)
> >> >> >>> >> >> >>> > {
> >> >> >>> >> >> >>> > try
> >> >> >>> >> >> >>> > {
> >> >> >>> >> >> >>> > call_http(myAddressA1)
> >> >> >>> >> >> >>> > }
> >> >> >>> >> >> >>> > catch(Exception x)
> >> >> >>> >> >> >>> > {
> >> >> >>> >> >> >>> > //Call addressA2
> >> >> >>> >> >> >>> > ....
> >> >> >>> >> >> >>> > }
> >> >> >>> >> >> >>> > }
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>> > I've tried the onException() mechanism and the
> >> >> >>> deadLetterChannel
> >> >> >>> >> >> >>> processor
> >> >> >>> >> >> >>> > but I never get working my route.
> >> >> >>> >> >> >>> >
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>> --
> >> >> >>> >> >> >>> Claus Ibsen
> >> >> >>> >> >> >>> Apache Camel Committer
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>> Open Source Integration: http://fusesource.com
> >> >> >>> >> >> >>> Blog: http://davsclaus.blogspot.com/
> >> >> >>> >> >> >>> Twitter: http://twitter.com/davsclaus
> >> >> >>> >> >> >>>
> >> >> >>> >> >> >>
> >> >> >>> >> >> >
> >> >> >>> >> >> >
> >> >> >>> >> >> >
> >> >> >>> >> >> > --
> >> >> >>> >> >> > Claus Ibsen
> >> >> >>> >> >> > Apache Camel Committer
> >> >> >>> >> >> >
> >> >> >>> >> >> > Open Source Integration: http://fusesource.com
> >> >> >>> >> >> > Blog: http://davsclaus.blogspot.com/
> >> >> >>> >> >> > Twitter: http://twitter.com/davsclaus
> >> >> >>> >> >> >
> >> >> >>> >> >>
> >> >> >>> >> >>
> >> >> >>> >> >>
> >> >> >>> >> >> --
> >> >> >>> >> >> Claus Ibsen
> >> >> >>> >> >> Apache Camel Committer
> >> >> >>> >> >>
> >> >> >>> >> >> Open Source Integration: http://fusesource.com
> >> >> >>> >> >> Blog: http://davsclaus.blogspot.com/
> >> >> >>> >> >> Twitter: http://twitter.com/davsclaus
> >> >> >>> >> >>
> >> >> >>> >> >
> >> >> >>> >>
> >> >> >>> >>
> >> >> >>> >>
> >> >> >>> >> --
> >> >> >>> >> Claus Ibsen
> >> >> >>> >> Apache Camel Committer
> >> >> >>> >>
> >> >> >>> >> Open Source Integration: http://fusesource.com
> >> >> >>> >> Blog: http://davsclaus.blogspot.com/
> >> >> >>> >> Twitter: http://twitter.com/davsclaus
> >> >> >>> >>
> >> >> >>> >
> >> >> >>>
> >> >> >>>
> >> >> >>>
> >> >> >>> --
> >> >> >>> Claus Ibsen
> >> >> >>> Apache Camel Committer
> >> >> >>>
> >> >> >>> Open Source Integration: http://fusesource.com
> >> >> >>> Blog: http://davsclaus.blogspot.com/
> >> >> >>> Twitter: http://twitter.com/davsclaus
> >> >> >>>
> >> >> >>
> >> >> >
> >> >> >
> >> >> >
> >> >> > --
> >> >> > Claus Ibsen
> >> >> > Apache Camel Committer
> >> >> >
> >> >> > Open Source Integration: http://fusesource.com
> >> >> > Blog: http://davsclaus.blogspot.com/
> >> >> > Twitter: http://twitter.com/davsclaus
> >> >> >
> >> >>
> >> >>
> >> >>
> >> >> --
> >> >> Claus Ibsen
> >> >> Apache Camel Committer
> >> >>
> >> >> Open Source Integration: http://fusesource.com
> >> >> Blog: http://davsclaus.blogspot.com/
> >> >> Twitter: http://twitter.com/davsclaus
> >> >>
> >> >
> >>
> >>
> >>
> >> --
> >> Claus Ibsen
> >> Apache Camel Committer
> >>
> >> Open Source Integration: http://fusesource.com
> >> Blog: http://davsclaus.blogspot.com/
> >> Twitter: http://twitter.com/davsclaus
> >>
> >
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
On Tue, May 19, 2009 at 10:52 AM, Nasim Anza <na...@googlemail.com> wrote:
> Hi,
>
> Yes the pipeline EIP answers to my needs.
> I've tried to do it using the pipes and filters EIP pattern as suggested.
>
> The first block "endpointA" works and its output is the input of the
> endpointB block but I got the following exception when myServiceB is
> requested : "org.apache.commons.httpclient.NoHttpResponseException: The
> server localhost failed to respond"
Well look at the HTTP server and see why it did not reply. Maybe
something went wrong on this server so it could no reply.
>
> It seems very simple but hard to get it working ,-)
>
> My route can be displayed on "http://pastebin.com/m2009204d" :
>
> from("jbi:endpoint:myClientEndPoint").to("direct:pipelinetest");
>
> from("direct:pipelinetest")
> .pipeline("direct:endpointA", "direct:endpointB", "direct:endpointC");
>
>
> from("direct:endpointA")
> .setHeader(HttpProducer.HTTP_URI).constant("http://localhost/myServiceA")
> .setHeader("SOAPAction", constant("mynamespace#OperationA"))
> .setHeader("Content-Type", constant("text/xml;charset=ISO-8859-1"))
> .to("http://localhost/myServiceA");
>
> from("direct:endpointA")
> .setHeader(HttpProducer.HTTP_URI).constant("http://localhost/myServiceB")
> .setHeader("SOAPAction", constant("mynamespace#OperationB"))
> .setHeader("Content-Type", constant("text/xml;charset=ISO-8859-1"))
> .to("http://localhost/myServiceB");
>
> from("direct:endpointC")
> .to("log:display output");
>
> Thanks for your help.
> nasmo
>
>
> On Mon, May 18, 2009 at 4:05 PM, Claus Ibsen <cl...@gmail.com> wrote:
>
>> On Mon, May 18, 2009 at 3:56 PM, Nasim Anza <na...@googlemail.com>
>> wrote:
>> > Thanks Claus for your help.
>> >
>> > Actually the problem I got is not related to the FailOverProcessor
>> mechanism
>> > but in the global route:
>> > I would like that the result of a given HTTP endoint goes into another
>> HTTP
>> > endpoint.
>> > For example the result of HTTP endpointA will be redirected to the HTTP
>> > endpoint B.... etc
>> That is the pipes and filters EIP pattern:
>> http://camel.apache.org/pipes-and-filters.html
>>
>> So basically its like
>> .to("a", "b", "c");
>> where the output from a is input to b and output from b is input to c and
>> so on.
>>
>> I will suggest that you try without the failover and get this
>> implemented so you got the "normal situation" covered.
>> When that is working we can take a look again how to do error handling
>> and failover.
>>
>>
>> >
>> > I've pasted my route and my FailOver Processor on pastbin URL :
>> > http://mmo.pastebin.com/m7160e173
>> >
>> > Please let me know if I have any error or mistake in the code.
>> >
>> > Note : the appliA1, appliA2, .appliX are webservices that return valid
>> SOAP
>> > XMLs
>> >
>> > Thanks a lot for any help
>> >
>> > Nasmo
>> >
>> >
>> > On Sat, May 16, 2009 at 4:52 PM, Claus Ibsen <cl...@gmail.com>
>> wrote:
>> >
>> >> Hi
>> >>
>> >> I have created an example how to do your own custom processor as
>> >> failover. Its based on an unit test and the code is here:
>> >>
>> >>
>> >>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/issues/CustomFailveOverProcessor.java
>> >>
>> >> The code is based on Camel 2.0, but you can do the same in Camel 1.x.
>> >>
>> >>
>> >> On Sat, May 16, 2009 at 4:37 PM, Claus Ibsen <cl...@gmail.com>
>> >> wrote:
>> >> > Hi
>> >> >
>> >> > Sometimes its easier to read the code when there is quite a bit if you
>> >> > paste it using http://pastebin.com/ or the likes.
>> >> >
>> >> >
>> >> >
>> >> > On Fri, May 15, 2009 at 5:44 PM, Nasim Anza <nasmo2009@googlemail.com
>> >
>> >> wrote:
>> >> >> Thanks Claus for answers.
>> >> >>
>> >> >> My processor is working fine and it finds the URL to invoke but the
>> >> problem
>> >> >> is on the last step : the next endpoint is not called with right XML
>> >> input :
>> >> >>
>> >> >> Just to explain my actual problem :
>> >> >> Let's assume that my route is :
>> >> >>
>> >> >> from("direct:endpointA")
>> >> >> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >> >> .process(myFailOverProcessor("direct:endpointB")); //forward HTTP
>> >> response
>> >> >> to the direct:endpointB
>> >> >>
>> >> >> from("direct:endpointB")
>> >> >> .to("log:display the XML input"); //just display it to compare XMLs
>> >> >>
>> >> >> The displayed XML on the "log:..." endpoint doesn't correspond to the
>> >> http
>> >> >> response of "http://myAddressA"...
>> >> >>
>> >> >> Here is my Processor class :
>> >> >>
>> >> >>
>> >> >> public class FailOverProcessor implements Processor{
>> >> >>
>> >> >> public FailOverProcessor(String endpoint) {
>> >> >> this.endpoint=endpoint;
>> >> >> }
>> >> >>
>> >> >> public void process(Exchange exchange) throws Exception {
>> >> >> Exchange out = null;
>> >> >> int index = 0;
>> >> >> out = processExchange(exchange);
>> >> >>
>> >> >> while (exchange.getException() != null){
>> >> >>
>> >> >> //reset the exchange exceptiuon
>> >> >> exchange.setException(null);
>> >> >>
>> >> >> if (index++ < 4 ) {
>> >> >> System.out.println(index+" : processExchange .....");
>> >> >>
>> >> >> out = processExchange(exchange);
>> >> >> }
>> >> >> }
>> >> >>
>> >> >> if(endpoint != null)
>> >> >> {
>> >> >> ProducerTemplate<Exchange> template =
>> >> >> exchange.getContext().createProducerTemplate();
>> >> >> if(out != null)
>> >> >> {
>> >> >>
>> >> >> Message responseOut = exchange.getOut();
>> >> >> int responseCode =
>> >> >> responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE,
>> Integer.class);
>> >> >> System.out.println("\n\n Response out \\n" + responseCode
>> +
>> >> >> responseOut.getBody(String.class));
>> >> >>
>> >> >> //I've tried all the these calls but no valid response
>> >> >> // template.send(endpoint,
>> exchange.getOut().getExchange());
>> >> >> // template.sendBody(endpoint, exchange.getBody());
>> >> >> template.send(endpoint, exchange);
>> >> >> }
>> >> >> }
>> >> >> }
>> >> >>
>> >> >> private Exchange processExchange(Exchange exchange) {
>> >> >>
>> >> >> Exchange out = null;
>> >> >>
>> >> >> try {
>> >> >>
>> >> >> //Define the strategy to use for processing message
>> >> >> String uri =
>> >> >>
>> >>
>> exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
>> >> >> System.out.println("Current URI ==> "+uri);
>> >> >>
>> >> >> //just for test
>> >> >> if(uri.equalsIgnoreCase("http://myAddressA"))
>> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> >> http://serverA/appli1");
>> >> >> else if(uri.equalsIgnoreCase("http://myAddressB"))
>> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> >> http://serverB/appli2");
>> >> >> else
>> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> >> http://serverC/error");
>> >> >>
>> >> >> ProducerTemplate<Exchange> template =
>> >> >> exchange.getContext().createProducerTemplate();
>> >> >>
>> >> >> out = template.send(uri, exchange);
>> >> >>
>> >> >> } catch (Throwable th) {
>> >> >> //Set the thrown exception
>> >> >> exchange.setException(th.getCause());
>> >> >> }
>> >> >>
>> >> >> return out;
>> >> >> }
>> >> >> }
>> >> >>
>> >> >> Thanks for your help
>> >> >> Nasmo
>> >> >>
>> >> >>
>> >> >>
>> >> >>
>> >> >> On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <cl...@gmail.com>
>> >> wrote:
>> >> >>
>> >> >>> You need to test the exchange afterwards if there was an exception.
>> >> >>>
>> >> >>> template.send(endpoint, exchange);
>> >> >>> if (exchange.getException() != null) {
>> >> >>> // ops it failed so call the next URI as fallback
>> >> >>> ...
>> >> >>> }
>> >> >>>
>> >> >>>
>> >> >>>
>> >> >>>
>> >> >>> >
>> >> >>> > Unfortunately this doesn't change anything on the SMIX console. I
>> >> have
>> >> >>> the
>> >> >>> > same error :
>> >> >>> >
>> >> >>> > FATAL - DeadLetterChannel - Failed delivery for
>> >> exchangeId:
>> >> >>> > ID-ROME/1982-1242375956166/0-
>> >> >>> > Handled by the failure
>> >> >>> processor:sendTo(Endpoint[direct:deadLetterChannel])
>> >> >>> >
>> >> >>> > Thanks for help
>> >> >>> >
>> >> >>> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <
>> claus.ibsen@gmail.com
>> >> >
>> >> >>> wrote:
>> >> >>> >
>> >> >>> >> Hi
>> >> >>> >>
>> >> >>> >> You should *not* route after your custom failover processor. You
>> >> >>> >> custom failover processor should be the end of the route (eg no
>> more
>> >> >>> >> .to after your processor).
>> >> >>> >>
>> >> >>> >>
>> >> >>> >>
>> >> >>> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <
>> >> nasmo2009@googlemail.com>
>> >> >>> >> wrote:
>> >> >>> >> > Hi,
>> >> >>> >> >
>> >> >>> >> > I’ve tried this solution:
>> >> >>> >> > I started by developing a processor that loops on URIs until
>> >> getting a
>> >> >>> >> valid
>> >> >>> >> > answer.
>> >> >>> >> > The only problem is my route is interrupted at the end of the
>> >> first
>> >> >>> >> > processing, so no way to pass from first block (addressA) to
>> next
>> >> >>> block
>> >> >>> >> > (AddressB).
>> >> >>> >> >
>> >> >>> >> > The process() method loops on all URI until getting the valid
>> URI.
>> >> >>> This
>> >> >>> >> > works but after that I got a fatal error and the route flow was
>> >> >>> >> interrupted.
>> >> >>> >> > Below the error I got on ServiceMix console:
>> >> >>> >> >
>> >> >>> >> > ----------------
>> >> >>> >> >
>> >> >>> >> > FATAL - DeadLetterChannel - Failed delivery for
>> >> >>> exchangeId:
>> >> >>> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure
>> processor:
>> >> >>> >> > sendTo(Endpoint[direct:deadLetterChannel])
>> >> >>> >> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
>> >> >>> >> doIntercept
>> >> >>> >> > INFO: Interceptor has thrown exception, unwinding now
>> >> >>> >> > org.apache.xerces.dom.TextImpl
>> >> >>> >> >
>> >> >>> >> > ----------------
>> >> >>> >> >
>> >> >>> >> > Here is my Camel route:
>> >> >>> >> >
>> >> >>> >> > * //Declare Deadletter processor*
>> >> >>> >> >
>> >> >>> >> >
>> >> >>> >>
>> >> >>>
>> >>
>> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
>> >> >>> >> > *
>> >> >>> >> >
>> >> >>> >> > * //Declare global exception*
>> >> >>> >> >
>> >> >>> >> > *onException(Exception.class).maximumRedeliveries(5) //5 :
>> because
>> >> I
>> >> >>> have
>> >> >>> >> 5
>> >> >>> >> > address maximum to call*
>> >> >>> >> >
>> >> >>> >> > *final Processor myprocessor() = new Processor(Exchange
>> exchange)
>> >> >>> throws
>> >> >>> >> > Exception{*
>> >> >>> >> > **
>> >> >>> >> >
>> >> >>> >> > *ProducerTemplate<Exchange> template
>> >> >>> >> > exchange.getContext().createProducerTemplate();
>> >> >>> >> > String uri =
>> >> >>> >> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
>> >> >>> >> > *
>> >> >>> >> >
>> >> >>> >> > *//This method returns the valid list depending on the current
>> >> http
>> >> >>> URI*
>> >> >>> >> >
>> >> >>> >> > *List<Strig> uris = getUriList(uri);*
>> >> >>> >> >
>> >> >>> >> > *for (String uri : uris) {*
>> >> >>> >> >
>> >> >>> >> > * try {*
>> >> >>> >> >
>> >> >>> >> > * template.send(uri, exchange);*
>> >> >>> >> >
>> >> >>> >> > * } catch (Exception e) {*
>> >> >>> >> >
>> >> >>> >> > * exchange.setExceptipn(e);*
>> >> >>> >> >
>> >> >>> >> > * }*
>> >> >>> >> >
>> >> >>> >> > * if (exchange.getException() == null) {*
>> >> >>> >> >
>> >> >>> >> > * return;
>> >> >>> >> > }
>> >> >>> >> > }
>> >> >>> >> > }*
>> >> >>> >> >
>> >> >>> >> > * *
>> >> >>> >> >
>> >> >>> >> > *from("direct:endpointA")
>> >> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >> >>> >> > .process(myUrlLookerProcessor())
>> >> >>> >> > .to("direct:endPointB")*
>> >> >>> >> >
>> >> >>> >> > *from("direct:endpointB")
>> >> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>> >> >>> >> > .process(myUrlLookerProcessor())
>> >> >>> >> > .to("direct:endPointC")*
>> >> >>> >> >
>> >> >>> >> > *
>> >> >>> >> > from("direct:endPointC")
>> >> >>> >> > .to("xquery:response.xml");*
>> >> >>> >> >
>> >> >>> >> > *from("direct:letter")
>> >> >>> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
>> >> >>> >> >
>> >> >>> >> >
>> >> >>> >> >
>> >> >>> >> > Thanks in advance for help.
>> >> >>> >> >
>> >> >>> >> > Nasmo
>> >> >>> >> >
>> >> >>> >> >
>> >> >>> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <
>> >> claus.ibsen@gmail.com>
>> >> >>> >> wrote:
>> >> >>> >> >
>> >> >>> >> >> Hi
>> >> >>> >> >>
>> >> >>> >> >> BTW You can also always just use a Processor and implement the
>> >> >>> >> >> failover logic yourself as pure Java with try .. catch and use
>> >> the
>> >> >>> >> >> ProducerTemplate to send the exchange to the endpoint based on
>> >> the
>> >> >>> >> >> URI.
>> >> >>> >> >>
>> >> >>> >> >> Something like
>> >> >>> >> >> ProducerTemplate template = // get it from CamelContext and
>> get
>> >> it
>> >> >>> once
>> >> >>> >> >> List<Strig> uris = ...
>> >> >>> >> >>
>> >> >>> >> >> for (String uri : uris) {
>> >> >>> >> >> try {
>> >> >>> >> >> template.send(uri, exchange);
>> >> >>> >> >> } catch (Exception e) {
>> >> >>> >> >> exchange.setExceptipn(e);
>> >> >>> >> >> }
>> >> >>> >> >> if (exchange.getException() == null) {
>> >> >>> >> >> return;
>> >> >>> >> >> }
>> >> >>> >> >> }
>> >> >>> >> >>
>> >> >>> >> >>
>> >> >>> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <
>> >> claus.ibsen@gmail.com>
>> >> >>> >> >> wrote:
>> >> >>> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
>> >> >>> nasmo2009@googlemail.com
>> >> >>> >> >
>> >> >>> >> >> wrote:
>> >> >>> >> >> >> Thanks Claus for your quick answer.
>> >> >>> >> >> >>
>> >> >>> >> >> >> I downloaded the source of camel 2.0 and I looked at the
>> >> >>> >> >> >> FailOverLoadBalancer class. I think that this could answer
>> to
>> >> my
>> >> >>> >> >> question.
>> >> >>> >> >> >> I've tried to adapt the code to my requirement but I have
>> some
>> >> >>> >> questions
>> >> >>> >> >> >> about the list of processors used in this class :
>> >> >>> >> >> >>
>> >> >>> >> >> >> 1. I don't know How to create or initialize the processors
>> >> used
>> >> >>> for
>> >> >>> >> >> >> balancing user requests ?
>> >> >>> >> >> >>
>> >> >>> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
>> >> >>> >> >> >>
>> >> >>> >> >> >> 3. Whait is the syntaxe (maybe something like new
>> >> >>> >> Processor(myHttpURL))
>> >> >>> >> >> > Hi
>> >> >>> >> >> >
>> >> >>> >> >> > Yeah there is no nice DSL support for it and the
>> loadbalance()
>> >> DSL
>> >> >>> >> >> > does not have a nice support for custom load balancer.
>> >> >>> >> >> > So that is something we might need to improve in the future.
>> I
>> >> have
>> >> >>> to
>> >> >>> >> >> > remember this thread.
>> >> >>> >> >> >
>> >> >>> >> >> > So what you basically have to do is to add your custom load
>> >> >>> balancer
>> >> >>> >> >> > as a processor, so use the process() DSL.
>> >> >>> >> >> >
>> >> >>> >> >> > And your custom fail over loadbalancer can accept a list of
>> >> >>> endpoints
>> >> >>> >> >> > to select among. You can wrap an endpoint to a processor
>> >> >>> >> >> > with the SendToProcessor.
>> >> >>> >> >> >
>> >> >>> >> >> > Something like this
>> >> >>> >> >> >
>> >> >>> >> >> > MyFailover my = new MyFailoverProcessor()l;
>> >> >>> >> >> > my.addEndpoint("foo");
>> >> >>> >> >> > my.addEndpoint("bar");
>> >> >>> >> >> >
>> >> >>> >> >> >
>> >> >>> >> >> > And in the route DSL you just route to your processor
>> >> >>> >> >> > from(x).process(my);
>> >> >>> >> >> >
>> >> >>> >> >> > And in the addEndpoint method you add the endpoint by
>> wrapping
>> >> it
>> >> >>> with
>> >> >>> >> >> > a SendToProcessor so you can add it to the
>> LoadBalancerSupport
>> >> >>> class.
>> >> >>> >> >> >
>> >> >>> >> >> > See how it goes and ask again tomorrow when I am back in the
>> >> office
>> >> >>> >> >> > and can better work. As I sit now with the laptop in the
>> living
>> >> >>> room.
>> >> >>> >> >> >
>> >> >>> >> >> >
>> >> >>> >> >> >>
>> >> >>> >> >> >> Thanks for help
>> >> >>> >> >> >>
>> >> >>> >> >> >>
>> >> >>> >> >> >>
>> >> >>> >> >> >>
>> >> >>> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
>> >> >>> claus.ibsen@gmail.com
>> >> >>> >> >
>> >> >>> >> >> wrote:
>> >> >>> >> >> >>
>> >> >>> >> >> >>> Hi
>> >> >>> >> >> >>>
>> >> >>> >> >> >>> There are load balancers with Camel
>> >> >>> >> >> >>> http://camel.apache.org/load-balancer.html
>> >> >>> >> >> >>>
>> >> >>> >> >> >>> And there is a failover load balancer as well that can do
>> a
>> >> >>> simple
>> >> >>> >> try
>> >> >>> >> >> >>> the next endpoint until success kinda style.
>> >> >>> >> >> >>> Its a bit primitive at the moment and we would like to
>> >> improve
>> >> >>> that
>> >> >>> >> in
>> >> >>> >> >> >>> the future.
>> >> >>> >> >> >>>
>> >> >>> >> >> >>> But it allows you to implement your own load balancer and
>> do
>> >> your
>> >> >>> >> >> >>> strategy how you like it.
>> >> >>> >> >> >>>
>> >> >>> >> >> >>> Any feedback for features that could be needed for a more
>> >> >>> advanced
>> >> >>> >> >> >>> failover loadbalancer is much welcome.
>> >> >>> >> >> >>>
>> >> >>> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But
>> >> you
>> >> >>> can
>> >> >>> >> >> >>> check the source code for 2.0 and create your own kinda to
>> >> use in
>> >> >>> >> 1.x.
>> >> >>> >> >> >>>
>> >> >>> >> >> >>>
>> >> >>> >> >>
>> >> >>> >>
>> >> >>>
>> >>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>> >> >>> >> >> >>>
>> >> >>> >> >> >>>
>> >> >>> >> >> >>>
>> >> >>> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
>> >> >>> >> nasmo2009@googlemail.com
>> >> >>> >> >> >
>> >> >>> >> >> >>> wrote:
>> >> >>> >> >> >>> > Hi,
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > I would like to implement the following route with Camel
>> >> 1.6 :
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > from("direct:endpointA")
>> >> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
>> >> http://myAddressA")
>> >> >>> >> >> >>> > .to("http://xxxxxx")
>> >> >>> >> >> >>> > .to("direct:endPointB")
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > from("direct:endpointB")
>> >> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
>> >> http://myAddressB")
>> >> >>> >> >> >>> > .to("http://xxxxxx")
>> >> >>> >> >> >>> > .to("direct:endPointC")
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > from("direct:endPointC")
>> >> >>> >> >> >>> > .to("xquery:response.xml");
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > This route works fine if both URLs : http://myAddressAand
>> >> >>> >> >> >>> > http://myAddressBare accessible and no error occurs
>> during
>> >> the
>> >> >>> >> >> >>> > invocation.
>> >> >>> >> >> >>> > Unfortunately, sometimes these services become
>> unreachable
>> >> and
>> >> >>> I
>> >> >>> >> >> would
>> >> >>> >> >> >>> like
>> >> >>> >> >> >>> > to try other URLs until getting valid answer:
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > If an exception happens when calling the URL
>> >> http:/:myAddressA,
>> >> >>> I
>> >> >>> >> >> would
>> >> >>> >> >> >>> like
>> >> >>> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2,
>> ...until
>> >> >>> getting
>> >> >>> >> >> valid
>> >> >>> >> >> >>> > HTTP response.
>> >> >>> >> >> >>> > The same thing with myAddressB ==> myAddressB1,
>> >> myAddressB2,
>> >> >>> ...
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > With java this could be simply coded like following :
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > try
>> >> >>> >> >> >>> > {
>> >> >>> >> >> >>> > call_http(myAddressA)
>> >> >>> >> >> >>> > }
>> >> >>> >> >> >>> > catch(Throwable th)
>> >> >>> >> >> >>> > {
>> >> >>> >> >> >>> > try
>> >> >>> >> >> >>> > {
>> >> >>> >> >> >>> > call_http(myAddressA1)
>> >> >>> >> >> >>> > }
>> >> >>> >> >> >>> > catch(Exception x)
>> >> >>> >> >> >>> > {
>> >> >>> >> >> >>> > //Call addressA2
>> >> >>> >> >> >>> > ....
>> >> >>> >> >> >>> > }
>> >> >>> >> >> >>> > }
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>> > I've tried the onException() mechanism and the
>> >> >>> deadLetterChannel
>> >> >>> >> >> >>> processor
>> >> >>> >> >> >>> > but I never get working my route.
>> >> >>> >> >> >>> >
>> >> >>> >> >> >>>
>> >> >>> >> >> >>>
>> >> >>> >> >> >>>
>> >> >>> >> >> >>> --
>> >> >>> >> >> >>> Claus Ibsen
>> >> >>> >> >> >>> Apache Camel Committer
>> >> >>> >> >> >>>
>> >> >>> >> >> >>> Open Source Integration: http://fusesource.com
>> >> >>> >> >> >>> Blog: http://davsclaus.blogspot.com/
>> >> >>> >> >> >>> Twitter: http://twitter.com/davsclaus
>> >> >>> >> >> >>>
>> >> >>> >> >> >>
>> >> >>> >> >> >
>> >> >>> >> >> >
>> >> >>> >> >> >
>> >> >>> >> >> > --
>> >> >>> >> >> > Claus Ibsen
>> >> >>> >> >> > Apache Camel Committer
>> >> >>> >> >> >
>> >> >>> >> >> > Open Source Integration: http://fusesource.com
>> >> >>> >> >> > Blog: http://davsclaus.blogspot.com/
>> >> >>> >> >> > Twitter: http://twitter.com/davsclaus
>> >> >>> >> >> >
>> >> >>> >> >>
>> >> >>> >> >>
>> >> >>> >> >>
>> >> >>> >> >> --
>> >> >>> >> >> Claus Ibsen
>> >> >>> >> >> Apache Camel Committer
>> >> >>> >> >>
>> >> >>> >> >> Open Source Integration: http://fusesource.com
>> >> >>> >> >> Blog: http://davsclaus.blogspot.com/
>> >> >>> >> >> Twitter: http://twitter.com/davsclaus
>> >> >>> >> >>
>> >> >>> >> >
>> >> >>> >>
>> >> >>> >>
>> >> >>> >>
>> >> >>> >> --
>> >> >>> >> Claus Ibsen
>> >> >>> >> Apache Camel Committer
>> >> >>> >>
>> >> >>> >> Open Source Integration: http://fusesource.com
>> >> >>> >> Blog: http://davsclaus.blogspot.com/
>> >> >>> >> Twitter: http://twitter.com/davsclaus
>> >> >>> >>
>> >> >>> >
>> >> >>>
>> >> >>>
>> >> >>>
>> >> >>> --
>> >> >>> Claus Ibsen
>> >> >>> Apache Camel Committer
>> >> >>>
>> >> >>> Open Source Integration: http://fusesource.com
>> >> >>> Blog: http://davsclaus.blogspot.com/
>> >> >>> Twitter: http://twitter.com/davsclaus
>> >> >>>
>> >> >>
>> >> >
>> >> >
>> >> >
>> >> > --
>> >> > Claus Ibsen
>> >> > Apache Camel Committer
>> >> >
>> >> > Open Source Integration: http://fusesource.com
>> >> > Blog: http://davsclaus.blogspot.com/
>> >> > Twitter: http://twitter.com/davsclaus
>> >> >
>> >>
>> >>
>> >>
>> >> --
>> >> Claus Ibsen
>> >> Apache Camel Committer
>> >>
>> >> Open Source Integration: http://fusesource.com
>> >> Blog: http://davsclaus.blogspot.com/
>> >> Twitter: http://twitter.com/davsclaus
>> >>
>> >
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Nasim Anza <na...@googlemail.com>.
Hi,
Yes the pipeline EIP answers to my needs.
I've tried to do it using the pipes and filters EIP pattern as suggested.
The first block "endpointA" works and its output is the input of the
endpointB block but I got the following exception when myServiceB is
requested : "org.apache.commons.httpclient.NoHttpResponseException: The
server localhost failed to respond"
It seems very simple but hard to get it working ,-)
My route can be displayed on "http://pastebin.com/m2009204d" :
from("jbi:endpoint:myClientEndPoint").to("direct:pipelinetest");
from("direct:pipelinetest")
.pipeline("direct:endpointA", "direct:endpointB", "direct:endpointC");
from("direct:endpointA")
.setHeader(HttpProducer.HTTP_URI).constant("http://localhost/myServiceA")
.setHeader("SOAPAction", constant("mynamespace#OperationA"))
.setHeader("Content-Type", constant("text/xml;charset=ISO-8859-1"))
.to("http://localhost/myServiceA");
from("direct:endpointA")
.setHeader(HttpProducer.HTTP_URI).constant("http://localhost/myServiceB")
.setHeader("SOAPAction", constant("mynamespace#OperationB"))
.setHeader("Content-Type", constant("text/xml;charset=ISO-8859-1"))
.to("http://localhost/myServiceB");
from("direct:endpointC")
.to("log:display output");
Thanks for your help.
nasmo
On Mon, May 18, 2009 at 4:05 PM, Claus Ibsen <cl...@gmail.com> wrote:
> On Mon, May 18, 2009 at 3:56 PM, Nasim Anza <na...@googlemail.com>
> wrote:
> > Thanks Claus for your help.
> >
> > Actually the problem I got is not related to the FailOverProcessor
> mechanism
> > but in the global route:
> > I would like that the result of a given HTTP endoint goes into another
> HTTP
> > endpoint.
> > For example the result of HTTP endpointA will be redirected to the HTTP
> > endpoint B.... etc
> That is the pipes and filters EIP pattern:
> http://camel.apache.org/pipes-and-filters.html
>
> So basically its like
> .to("a", "b", "c");
> where the output from a is input to b and output from b is input to c and
> so on.
>
> I will suggest that you try without the failover and get this
> implemented so you got the "normal situation" covered.
> When that is working we can take a look again how to do error handling
> and failover.
>
>
> >
> > I've pasted my route and my FailOver Processor on pastbin URL :
> > http://mmo.pastebin.com/m7160e173
> >
> > Please let me know if I have any error or mistake in the code.
> >
> > Note : the appliA1, appliA2, .appliX are webservices that return valid
> SOAP
> > XMLs
> >
> > Thanks a lot for any help
> >
> > Nasmo
> >
> >
> > On Sat, May 16, 2009 at 4:52 PM, Claus Ibsen <cl...@gmail.com>
> wrote:
> >
> >> Hi
> >>
> >> I have created an example how to do your own custom processor as
> >> failover. Its based on an unit test and the code is here:
> >>
> >>
> >>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/issues/CustomFailveOverProcessor.java
> >>
> >> The code is based on Camel 2.0, but you can do the same in Camel 1.x.
> >>
> >>
> >> On Sat, May 16, 2009 at 4:37 PM, Claus Ibsen <cl...@gmail.com>
> >> wrote:
> >> > Hi
> >> >
> >> > Sometimes its easier to read the code when there is quite a bit if you
> >> > paste it using http://pastebin.com/ or the likes.
> >> >
> >> >
> >> >
> >> > On Fri, May 15, 2009 at 5:44 PM, Nasim Anza <nasmo2009@googlemail.com
> >
> >> wrote:
> >> >> Thanks Claus for answers.
> >> >>
> >> >> My processor is working fine and it finds the URL to invoke but the
> >> problem
> >> >> is on the last step : the next endpoint is not called with right XML
> >> input :
> >> >>
> >> >> Just to explain my actual problem :
> >> >> Let's assume that my route is :
> >> >>
> >> >> from("direct:endpointA")
> >> >> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >> >> .process(myFailOverProcessor("direct:endpointB")); //forward HTTP
> >> response
> >> >> to the direct:endpointB
> >> >>
> >> >> from("direct:endpointB")
> >> >> .to("log:display the XML input"); //just display it to compare XMLs
> >> >>
> >> >> The displayed XML on the "log:..." endpoint doesn't correspond to the
> >> http
> >> >> response of "http://myAddressA"...
> >> >>
> >> >> Here is my Processor class :
> >> >>
> >> >>
> >> >> public class FailOverProcessor implements Processor{
> >> >>
> >> >> public FailOverProcessor(String endpoint) {
> >> >> this.endpoint=endpoint;
> >> >> }
> >> >>
> >> >> public void process(Exchange exchange) throws Exception {
> >> >> Exchange out = null;
> >> >> int index = 0;
> >> >> out = processExchange(exchange);
> >> >>
> >> >> while (exchange.getException() != null){
> >> >>
> >> >> //reset the exchange exceptiuon
> >> >> exchange.setException(null);
> >> >>
> >> >> if (index++ < 4 ) {
> >> >> System.out.println(index+" : processExchange .....");
> >> >>
> >> >> out = processExchange(exchange);
> >> >> }
> >> >> }
> >> >>
> >> >> if(endpoint != null)
> >> >> {
> >> >> ProducerTemplate<Exchange> template =
> >> >> exchange.getContext().createProducerTemplate();
> >> >> if(out != null)
> >> >> {
> >> >>
> >> >> Message responseOut = exchange.getOut();
> >> >> int responseCode =
> >> >> responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE,
> Integer.class);
> >> >> System.out.println("\n\n Response out \\n" + responseCode
> +
> >> >> responseOut.getBody(String.class));
> >> >>
> >> >> //I've tried all the these calls but no valid response
> >> >> // template.send(endpoint,
> exchange.getOut().getExchange());
> >> >> // template.sendBody(endpoint, exchange.getBody());
> >> >> template.send(endpoint, exchange);
> >> >> }
> >> >> }
> >> >> }
> >> >>
> >> >> private Exchange processExchange(Exchange exchange) {
> >> >>
> >> >> Exchange out = null;
> >> >>
> >> >> try {
> >> >>
> >> >> //Define the strategy to use for processing message
> >> >> String uri =
> >> >>
> >>
> exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
> >> >> System.out.println("Current URI ==> "+uri);
> >> >>
> >> >> //just for test
> >> >> if(uri.equalsIgnoreCase("http://myAddressA"))
> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> >> http://serverA/appli1");
> >> >> else if(uri.equalsIgnoreCase("http://myAddressB"))
> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> >> http://serverB/appli2");
> >> >> else
> >> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> >> http://serverC/error");
> >> >>
> >> >> ProducerTemplate<Exchange> template =
> >> >> exchange.getContext().createProducerTemplate();
> >> >>
> >> >> out = template.send(uri, exchange);
> >> >>
> >> >> } catch (Throwable th) {
> >> >> //Set the thrown exception
> >> >> exchange.setException(th.getCause());
> >> >> }
> >> >>
> >> >> return out;
> >> >> }
> >> >> }
> >> >>
> >> >> Thanks for your help
> >> >> Nasmo
> >> >>
> >> >>
> >> >>
> >> >>
> >> >> On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <cl...@gmail.com>
> >> wrote:
> >> >>
> >> >>> You need to test the exchange afterwards if there was an exception.
> >> >>>
> >> >>> template.send(endpoint, exchange);
> >> >>> if (exchange.getException() != null) {
> >> >>> // ops it failed so call the next URI as fallback
> >> >>> ...
> >> >>> }
> >> >>>
> >> >>>
> >> >>>
> >> >>>
> >> >>> >
> >> >>> > Unfortunately this doesn't change anything on the SMIX console. I
> >> have
> >> >>> the
> >> >>> > same error :
> >> >>> >
> >> >>> > FATAL - DeadLetterChannel - Failed delivery for
> >> exchangeId:
> >> >>> > ID-ROME/1982-1242375956166/0-
> >> >>> > Handled by the failure
> >> >>> processor:sendTo(Endpoint[direct:deadLetterChannel])
> >> >>> >
> >> >>> > Thanks for help
> >> >>> >
> >> >>> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <
> claus.ibsen@gmail.com
> >> >
> >> >>> wrote:
> >> >>> >
> >> >>> >> Hi
> >> >>> >>
> >> >>> >> You should *not* route after your custom failover processor. You
> >> >>> >> custom failover processor should be the end of the route (eg no
> more
> >> >>> >> .to after your processor).
> >> >>> >>
> >> >>> >>
> >> >>> >>
> >> >>> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <
> >> nasmo2009@googlemail.com>
> >> >>> >> wrote:
> >> >>> >> > Hi,
> >> >>> >> >
> >> >>> >> > I’ve tried this solution:
> >> >>> >> > I started by developing a processor that loops on URIs until
> >> getting a
> >> >>> >> valid
> >> >>> >> > answer.
> >> >>> >> > The only problem is my route is interrupted at the end of the
> >> first
> >> >>> >> > processing, so no way to pass from first block (addressA) to
> next
> >> >>> block
> >> >>> >> > (AddressB).
> >> >>> >> >
> >> >>> >> > The process() method loops on all URI until getting the valid
> URI.
> >> >>> This
> >> >>> >> > works but after that I got a fatal error and the route flow was
> >> >>> >> interrupted.
> >> >>> >> > Below the error I got on ServiceMix console:
> >> >>> >> >
> >> >>> >> > ----------------
> >> >>> >> >
> >> >>> >> > FATAL - DeadLetterChannel - Failed delivery for
> >> >>> exchangeId:
> >> >>> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure
> processor:
> >> >>> >> > sendTo(Endpoint[direct:deadLetterChannel])
> >> >>> >> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
> >> >>> >> doIntercept
> >> >>> >> > INFO: Interceptor has thrown exception, unwinding now
> >> >>> >> > org.apache.xerces.dom.TextImpl
> >> >>> >> >
> >> >>> >> > ----------------
> >> >>> >> >
> >> >>> >> > Here is my Camel route:
> >> >>> >> >
> >> >>> >> > * //Declare Deadletter processor*
> >> >>> >> >
> >> >>> >> >
> >> >>> >>
> >> >>>
> >>
> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
> >> >>> >> > *
> >> >>> >> >
> >> >>> >> > * //Declare global exception*
> >> >>> >> >
> >> >>> >> > *onException(Exception.class).maximumRedeliveries(5) //5 :
> because
> >> I
> >> >>> have
> >> >>> >> 5
> >> >>> >> > address maximum to call*
> >> >>> >> >
> >> >>> >> > *final Processor myprocessor() = new Processor(Exchange
> exchange)
> >> >>> throws
> >> >>> >> > Exception{*
> >> >>> >> > **
> >> >>> >> >
> >> >>> >> > *ProducerTemplate<Exchange> template
> >> >>> >> > exchange.getContext().createProducerTemplate();
> >> >>> >> > String uri =
> >> >>> >> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
> >> >>> >> > *
> >> >>> >> >
> >> >>> >> > *//This method returns the valid list depending on the current
> >> http
> >> >>> URI*
> >> >>> >> >
> >> >>> >> > *List<Strig> uris = getUriList(uri);*
> >> >>> >> >
> >> >>> >> > *for (String uri : uris) {*
> >> >>> >> >
> >> >>> >> > * try {*
> >> >>> >> >
> >> >>> >> > * template.send(uri, exchange);*
> >> >>> >> >
> >> >>> >> > * } catch (Exception e) {*
> >> >>> >> >
> >> >>> >> > * exchange.setExceptipn(e);*
> >> >>> >> >
> >> >>> >> > * }*
> >> >>> >> >
> >> >>> >> > * if (exchange.getException() == null) {*
> >> >>> >> >
> >> >>> >> > * return;
> >> >>> >> > }
> >> >>> >> > }
> >> >>> >> > }*
> >> >>> >> >
> >> >>> >> > * *
> >> >>> >> >
> >> >>> >> > *from("direct:endpointA")
> >> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >> >>> >> > .process(myUrlLookerProcessor())
> >> >>> >> > .to("direct:endPointB")*
> >> >>> >> >
> >> >>> >> > *from("direct:endpointB")
> >> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> >> >>> >> > .process(myUrlLookerProcessor())
> >> >>> >> > .to("direct:endPointC")*
> >> >>> >> >
> >> >>> >> > *
> >> >>> >> > from("direct:endPointC")
> >> >>> >> > .to("xquery:response.xml");*
> >> >>> >> >
> >> >>> >> > *from("direct:letter")
> >> >>> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
> >> >>> >> >
> >> >>> >> >
> >> >>> >> >
> >> >>> >> > Thanks in advance for help.
> >> >>> >> >
> >> >>> >> > Nasmo
> >> >>> >> >
> >> >>> >> >
> >> >>> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <
> >> claus.ibsen@gmail.com>
> >> >>> >> wrote:
> >> >>> >> >
> >> >>> >> >> Hi
> >> >>> >> >>
> >> >>> >> >> BTW You can also always just use a Processor and implement the
> >> >>> >> >> failover logic yourself as pure Java with try .. catch and use
> >> the
> >> >>> >> >> ProducerTemplate to send the exchange to the endpoint based on
> >> the
> >> >>> >> >> URI.
> >> >>> >> >>
> >> >>> >> >> Something like
> >> >>> >> >> ProducerTemplate template = // get it from CamelContext and
> get
> >> it
> >> >>> once
> >> >>> >> >> List<Strig> uris = ...
> >> >>> >> >>
> >> >>> >> >> for (String uri : uris) {
> >> >>> >> >> try {
> >> >>> >> >> template.send(uri, exchange);
> >> >>> >> >> } catch (Exception e) {
> >> >>> >> >> exchange.setExceptipn(e);
> >> >>> >> >> }
> >> >>> >> >> if (exchange.getException() == null) {
> >> >>> >> >> return;
> >> >>> >> >> }
> >> >>> >> >> }
> >> >>> >> >>
> >> >>> >> >>
> >> >>> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <
> >> claus.ibsen@gmail.com>
> >> >>> >> >> wrote:
> >> >>> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
> >> >>> nasmo2009@googlemail.com
> >> >>> >> >
> >> >>> >> >> wrote:
> >> >>> >> >> >> Thanks Claus for your quick answer.
> >> >>> >> >> >>
> >> >>> >> >> >> I downloaded the source of camel 2.0 and I looked at the
> >> >>> >> >> >> FailOverLoadBalancer class. I think that this could answer
> to
> >> my
> >> >>> >> >> question.
> >> >>> >> >> >> I've tried to adapt the code to my requirement but I have
> some
> >> >>> >> questions
> >> >>> >> >> >> about the list of processors used in this class :
> >> >>> >> >> >>
> >> >>> >> >> >> 1. I don't know How to create or initialize the processors
> >> used
> >> >>> for
> >> >>> >> >> >> balancing user requests ?
> >> >>> >> >> >>
> >> >>> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
> >> >>> >> >> >>
> >> >>> >> >> >> 3. Whait is the syntaxe (maybe something like new
> >> >>> >> Processor(myHttpURL))
> >> >>> >> >> > Hi
> >> >>> >> >> >
> >> >>> >> >> > Yeah there is no nice DSL support for it and the
> loadbalance()
> >> DSL
> >> >>> >> >> > does not have a nice support for custom load balancer.
> >> >>> >> >> > So that is something we might need to improve in the future.
> I
> >> have
> >> >>> to
> >> >>> >> >> > remember this thread.
> >> >>> >> >> >
> >> >>> >> >> > So what you basically have to do is to add your custom load
> >> >>> balancer
> >> >>> >> >> > as a processor, so use the process() DSL.
> >> >>> >> >> >
> >> >>> >> >> > And your custom fail over loadbalancer can accept a list of
> >> >>> endpoints
> >> >>> >> >> > to select among. You can wrap an endpoint to a processor
> >> >>> >> >> > with the SendToProcessor.
> >> >>> >> >> >
> >> >>> >> >> > Something like this
> >> >>> >> >> >
> >> >>> >> >> > MyFailover my = new MyFailoverProcessor()l;
> >> >>> >> >> > my.addEndpoint("foo");
> >> >>> >> >> > my.addEndpoint("bar");
> >> >>> >> >> >
> >> >>> >> >> >
> >> >>> >> >> > And in the route DSL you just route to your processor
> >> >>> >> >> > from(x).process(my);
> >> >>> >> >> >
> >> >>> >> >> > And in the addEndpoint method you add the endpoint by
> wrapping
> >> it
> >> >>> with
> >> >>> >> >> > a SendToProcessor so you can add it to the
> LoadBalancerSupport
> >> >>> class.
> >> >>> >> >> >
> >> >>> >> >> > See how it goes and ask again tomorrow when I am back in the
> >> office
> >> >>> >> >> > and can better work. As I sit now with the laptop in the
> living
> >> >>> room.
> >> >>> >> >> >
> >> >>> >> >> >
> >> >>> >> >> >>
> >> >>> >> >> >> Thanks for help
> >> >>> >> >> >>
> >> >>> >> >> >>
> >> >>> >> >> >>
> >> >>> >> >> >>
> >> >>> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
> >> >>> claus.ibsen@gmail.com
> >> >>> >> >
> >> >>> >> >> wrote:
> >> >>> >> >> >>
> >> >>> >> >> >>> Hi
> >> >>> >> >> >>>
> >> >>> >> >> >>> There are load balancers with Camel
> >> >>> >> >> >>> http://camel.apache.org/load-balancer.html
> >> >>> >> >> >>>
> >> >>> >> >> >>> And there is a failover load balancer as well that can do
> a
> >> >>> simple
> >> >>> >> try
> >> >>> >> >> >>> the next endpoint until success kinda style.
> >> >>> >> >> >>> Its a bit primitive at the moment and we would like to
> >> improve
> >> >>> that
> >> >>> >> in
> >> >>> >> >> >>> the future.
> >> >>> >> >> >>>
> >> >>> >> >> >>> But it allows you to implement your own load balancer and
> do
> >> your
> >> >>> >> >> >>> strategy how you like it.
> >> >>> >> >> >>>
> >> >>> >> >> >>> Any feedback for features that could be needed for a more
> >> >>> advanced
> >> >>> >> >> >>> failover loadbalancer is much welcome.
> >> >>> >> >> >>>
> >> >>> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But
> >> you
> >> >>> can
> >> >>> >> >> >>> check the source code for 2.0 and create your own kinda to
> >> use in
> >> >>> >> 1.x.
> >> >>> >> >> >>>
> >> >>> >> >> >>>
> >> >>> >> >>
> >> >>> >>
> >> >>>
> >>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
> >> >>> >> >> >>>
> >> >>> >> >> >>>
> >> >>> >> >> >>>
> >> >>> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
> >> >>> >> nasmo2009@googlemail.com
> >> >>> >> >> >
> >> >>> >> >> >>> wrote:
> >> >>> >> >> >>> > Hi,
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > I would like to implement the following route with Camel
> >> 1.6 :
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > from("direct:endpointA")
> >> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
> >> http://myAddressA")
> >> >>> >> >> >>> > .to("http://xxxxxx")
> >> >>> >> >> >>> > .to("direct:endPointB")
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > from("direct:endpointB")
> >> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
> >> http://myAddressB")
> >> >>> >> >> >>> > .to("http://xxxxxx")
> >> >>> >> >> >>> > .to("direct:endPointC")
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > from("direct:endPointC")
> >> >>> >> >> >>> > .to("xquery:response.xml");
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > This route works fine if both URLs : http://myAddressAand
> >> >>> >> >> >>> > http://myAddressBare accessible and no error occurs
> during
> >> the
> >> >>> >> >> >>> > invocation.
> >> >>> >> >> >>> > Unfortunately, sometimes these services become
> unreachable
> >> and
> >> >>> I
> >> >>> >> >> would
> >> >>> >> >> >>> like
> >> >>> >> >> >>> > to try other URLs until getting valid answer:
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > If an exception happens when calling the URL
> >> http:/:myAddressA,
> >> >>> I
> >> >>> >> >> would
> >> >>> >> >> >>> like
> >> >>> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2,
> ...until
> >> >>> getting
> >> >>> >> >> valid
> >> >>> >> >> >>> > HTTP response.
> >> >>> >> >> >>> > The same thing with myAddressB ==> myAddressB1,
> >> myAddressB2,
> >> >>> ...
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > With java this could be simply coded like following :
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > try
> >> >>> >> >> >>> > {
> >> >>> >> >> >>> > call_http(myAddressA)
> >> >>> >> >> >>> > }
> >> >>> >> >> >>> > catch(Throwable th)
> >> >>> >> >> >>> > {
> >> >>> >> >> >>> > try
> >> >>> >> >> >>> > {
> >> >>> >> >> >>> > call_http(myAddressA1)
> >> >>> >> >> >>> > }
> >> >>> >> >> >>> > catch(Exception x)
> >> >>> >> >> >>> > {
> >> >>> >> >> >>> > //Call addressA2
> >> >>> >> >> >>> > ....
> >> >>> >> >> >>> > }
> >> >>> >> >> >>> > }
> >> >>> >> >> >>> >
> >> >>> >> >> >>> > I've tried the onException() mechanism and the
> >> >>> deadLetterChannel
> >> >>> >> >> >>> processor
> >> >>> >> >> >>> > but I never get working my route.
> >> >>> >> >> >>> >
> >> >>> >> >> >>>
> >> >>> >> >> >>>
> >> >>> >> >> >>>
> >> >>> >> >> >>> --
> >> >>> >> >> >>> Claus Ibsen
> >> >>> >> >> >>> Apache Camel Committer
> >> >>> >> >> >>>
> >> >>> >> >> >>> Open Source Integration: http://fusesource.com
> >> >>> >> >> >>> Blog: http://davsclaus.blogspot.com/
> >> >>> >> >> >>> Twitter: http://twitter.com/davsclaus
> >> >>> >> >> >>>
> >> >>> >> >> >>
> >> >>> >> >> >
> >> >>> >> >> >
> >> >>> >> >> >
> >> >>> >> >> > --
> >> >>> >> >> > Claus Ibsen
> >> >>> >> >> > Apache Camel Committer
> >> >>> >> >> >
> >> >>> >> >> > Open Source Integration: http://fusesource.com
> >> >>> >> >> > Blog: http://davsclaus.blogspot.com/
> >> >>> >> >> > Twitter: http://twitter.com/davsclaus
> >> >>> >> >> >
> >> >>> >> >>
> >> >>> >> >>
> >> >>> >> >>
> >> >>> >> >> --
> >> >>> >> >> Claus Ibsen
> >> >>> >> >> Apache Camel Committer
> >> >>> >> >>
> >> >>> >> >> Open Source Integration: http://fusesource.com
> >> >>> >> >> Blog: http://davsclaus.blogspot.com/
> >> >>> >> >> Twitter: http://twitter.com/davsclaus
> >> >>> >> >>
> >> >>> >> >
> >> >>> >>
> >> >>> >>
> >> >>> >>
> >> >>> >> --
> >> >>> >> Claus Ibsen
> >> >>> >> Apache Camel Committer
> >> >>> >>
> >> >>> >> Open Source Integration: http://fusesource.com
> >> >>> >> Blog: http://davsclaus.blogspot.com/
> >> >>> >> Twitter: http://twitter.com/davsclaus
> >> >>> >>
> >> >>> >
> >> >>>
> >> >>>
> >> >>>
> >> >>> --
> >> >>> Claus Ibsen
> >> >>> Apache Camel Committer
> >> >>>
> >> >>> Open Source Integration: http://fusesource.com
> >> >>> Blog: http://davsclaus.blogspot.com/
> >> >>> Twitter: http://twitter.com/davsclaus
> >> >>>
> >> >>
> >> >
> >> >
> >> >
> >> > --
> >> > Claus Ibsen
> >> > Apache Camel Committer
> >> >
> >> > Open Source Integration: http://fusesource.com
> >> > Blog: http://davsclaus.blogspot.com/
> >> > Twitter: http://twitter.com/davsclaus
> >> >
> >>
> >>
> >>
> >> --
> >> Claus Ibsen
> >> Apache Camel Committer
> >>
> >> Open Source Integration: http://fusesource.com
> >> Blog: http://davsclaus.blogspot.com/
> >> Twitter: http://twitter.com/davsclaus
> >>
> >
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
On Mon, May 18, 2009 at 3:56 PM, Nasim Anza <na...@googlemail.com> wrote:
> Thanks Claus for your help.
>
> Actually the problem I got is not related to the FailOverProcessor mechanism
> but in the global route:
> I would like that the result of a given HTTP endoint goes into another HTTP
> endpoint.
> For example the result of HTTP endpointA will be redirected to the HTTP
> endpoint B.... etc
That is the pipes and filters EIP pattern:
http://camel.apache.org/pipes-and-filters.html
So basically its like
.to("a", "b", "c");
where the output from a is input to b and output from b is input to c and so on.
I will suggest that you try without the failover and get this
implemented so you got the "normal situation" covered.
When that is working we can take a look again how to do error handling
and failover.
>
> I've pasted my route and my FailOver Processor on pastbin URL :
> http://mmo.pastebin.com/m7160e173
>
> Please let me know if I have any error or mistake in the code.
>
> Note : the appliA1, appliA2, .appliX are webservices that return valid SOAP
> XMLs
>
> Thanks a lot for any help
>
> Nasmo
>
>
> On Sat, May 16, 2009 at 4:52 PM, Claus Ibsen <cl...@gmail.com> wrote:
>
>> Hi
>>
>> I have created an example how to do your own custom processor as
>> failover. Its based on an unit test and the code is here:
>>
>>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/issues/CustomFailveOverProcessor.java
>>
>> The code is based on Camel 2.0, but you can do the same in Camel 1.x.
>>
>>
>> On Sat, May 16, 2009 at 4:37 PM, Claus Ibsen <cl...@gmail.com>
>> wrote:
>> > Hi
>> >
>> > Sometimes its easier to read the code when there is quite a bit if you
>> > paste it using http://pastebin.com/ or the likes.
>> >
>> >
>> >
>> > On Fri, May 15, 2009 at 5:44 PM, Nasim Anza <na...@googlemail.com>
>> wrote:
>> >> Thanks Claus for answers.
>> >>
>> >> My processor is working fine and it finds the URL to invoke but the
>> problem
>> >> is on the last step : the next endpoint is not called with right XML
>> input :
>> >>
>> >> Just to explain my actual problem :
>> >> Let's assume that my route is :
>> >>
>> >> from("direct:endpointA")
>> >> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >> .process(myFailOverProcessor("direct:endpointB")); //forward HTTP
>> response
>> >> to the direct:endpointB
>> >>
>> >> from("direct:endpointB")
>> >> .to("log:display the XML input"); //just display it to compare XMLs
>> >>
>> >> The displayed XML on the "log:..." endpoint doesn't correspond to the
>> http
>> >> response of "http://myAddressA"...
>> >>
>> >> Here is my Processor class :
>> >>
>> >>
>> >> public class FailOverProcessor implements Processor{
>> >>
>> >> public FailOverProcessor(String endpoint) {
>> >> this.endpoint=endpoint;
>> >> }
>> >>
>> >> public void process(Exchange exchange) throws Exception {
>> >> Exchange out = null;
>> >> int index = 0;
>> >> out = processExchange(exchange);
>> >>
>> >> while (exchange.getException() != null){
>> >>
>> >> //reset the exchange exceptiuon
>> >> exchange.setException(null);
>> >>
>> >> if (index++ < 4 ) {
>> >> System.out.println(index+" : processExchange .....");
>> >>
>> >> out = processExchange(exchange);
>> >> }
>> >> }
>> >>
>> >> if(endpoint != null)
>> >> {
>> >> ProducerTemplate<Exchange> template =
>> >> exchange.getContext().createProducerTemplate();
>> >> if(out != null)
>> >> {
>> >>
>> >> Message responseOut = exchange.getOut();
>> >> int responseCode =
>> >> responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE, Integer.class);
>> >> System.out.println("\n\n Response out \\n" + responseCode +
>> >> responseOut.getBody(String.class));
>> >>
>> >> //I've tried all the these calls but no valid response
>> >> // template.send(endpoint, exchange.getOut().getExchange());
>> >> // template.sendBody(endpoint, exchange.getBody());
>> >> template.send(endpoint, exchange);
>> >> }
>> >> }
>> >> }
>> >>
>> >> private Exchange processExchange(Exchange exchange) {
>> >>
>> >> Exchange out = null;
>> >>
>> >> try {
>> >>
>> >> //Define the strategy to use for processing message
>> >> String uri =
>> >>
>> exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
>> >> System.out.println("Current URI ==> "+uri);
>> >>
>> >> //just for test
>> >> if(uri.equalsIgnoreCase("http://myAddressA"))
>> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> http://serverA/appli1");
>> >> else if(uri.equalsIgnoreCase("http://myAddressB"))
>> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> http://serverB/appli2");
>> >> else
>> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> >> http://serverC/error");
>> >>
>> >> ProducerTemplate<Exchange> template =
>> >> exchange.getContext().createProducerTemplate();
>> >>
>> >> out = template.send(uri, exchange);
>> >>
>> >> } catch (Throwable th) {
>> >> //Set the thrown exception
>> >> exchange.setException(th.getCause());
>> >> }
>> >>
>> >> return out;
>> >> }
>> >> }
>> >>
>> >> Thanks for your help
>> >> Nasmo
>> >>
>> >>
>> >>
>> >>
>> >> On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <cl...@gmail.com>
>> wrote:
>> >>
>> >>> You need to test the exchange afterwards if there was an exception.
>> >>>
>> >>> template.send(endpoint, exchange);
>> >>> if (exchange.getException() != null) {
>> >>> // ops it failed so call the next URI as fallback
>> >>> ...
>> >>> }
>> >>>
>> >>>
>> >>>
>> >>>
>> >>> >
>> >>> > Unfortunately this doesn't change anything on the SMIX console. I
>> have
>> >>> the
>> >>> > same error :
>> >>> >
>> >>> > FATAL - DeadLetterChannel - Failed delivery for
>> exchangeId:
>> >>> > ID-ROME/1982-1242375956166/0-
>> >>> > Handled by the failure
>> >>> processor:sendTo(Endpoint[direct:deadLetterChannel])
>> >>> >
>> >>> > Thanks for help
>> >>> >
>> >>> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <claus.ibsen@gmail.com
>> >
>> >>> wrote:
>> >>> >
>> >>> >> Hi
>> >>> >>
>> >>> >> You should *not* route after your custom failover processor. You
>> >>> >> custom failover processor should be the end of the route (eg no more
>> >>> >> .to after your processor).
>> >>> >>
>> >>> >>
>> >>> >>
>> >>> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <
>> nasmo2009@googlemail.com>
>> >>> >> wrote:
>> >>> >> > Hi,
>> >>> >> >
>> >>> >> > I’ve tried this solution:
>> >>> >> > I started by developing a processor that loops on URIs until
>> getting a
>> >>> >> valid
>> >>> >> > answer.
>> >>> >> > The only problem is my route is interrupted at the end of the
>> first
>> >>> >> > processing, so no way to pass from first block (addressA) to next
>> >>> block
>> >>> >> > (AddressB).
>> >>> >> >
>> >>> >> > The process() method loops on all URI until getting the valid URI.
>> >>> This
>> >>> >> > works but after that I got a fatal error and the route flow was
>> >>> >> interrupted.
>> >>> >> > Below the error I got on ServiceMix console:
>> >>> >> >
>> >>> >> > ----------------
>> >>> >> >
>> >>> >> > FATAL - DeadLetterChannel - Failed delivery for
>> >>> exchangeId:
>> >>> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
>> >>> >> > sendTo(Endpoint[direct:deadLetterChannel])
>> >>> >> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
>> >>> >> doIntercept
>> >>> >> > INFO: Interceptor has thrown exception, unwinding now
>> >>> >> > org.apache.xerces.dom.TextImpl
>> >>> >> >
>> >>> >> > ----------------
>> >>> >> >
>> >>> >> > Here is my Camel route:
>> >>> >> >
>> >>> >> > * //Declare Deadletter processor*
>> >>> >> >
>> >>> >> >
>> >>> >>
>> >>>
>> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
>> >>> >> > *
>> >>> >> >
>> >>> >> > * //Declare global exception*
>> >>> >> >
>> >>> >> > *onException(Exception.class).maximumRedeliveries(5) //5 : because
>> I
>> >>> have
>> >>> >> 5
>> >>> >> > address maximum to call*
>> >>> >> >
>> >>> >> > *final Processor myprocessor() = new Processor(Exchange exchange)
>> >>> throws
>> >>> >> > Exception{*
>> >>> >> > **
>> >>> >> >
>> >>> >> > *ProducerTemplate<Exchange> template
>> >>> >> > exchange.getContext().createProducerTemplate();
>> >>> >> > String uri =
>> >>> >> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
>> >>> >> > *
>> >>> >> >
>> >>> >> > *//This method returns the valid list depending on the current
>> http
>> >>> URI*
>> >>> >> >
>> >>> >> > *List<Strig> uris = getUriList(uri);*
>> >>> >> >
>> >>> >> > *for (String uri : uris) {*
>> >>> >> >
>> >>> >> > * try {*
>> >>> >> >
>> >>> >> > * template.send(uri, exchange);*
>> >>> >> >
>> >>> >> > * } catch (Exception e) {*
>> >>> >> >
>> >>> >> > * exchange.setExceptipn(e);*
>> >>> >> >
>> >>> >> > * }*
>> >>> >> >
>> >>> >> > * if (exchange.getException() == null) {*
>> >>> >> >
>> >>> >> > * return;
>> >>> >> > }
>> >>> >> > }
>> >>> >> > }*
>> >>> >> >
>> >>> >> > * *
>> >>> >> >
>> >>> >> > *from("direct:endpointA")
>> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >>> >> > .process(myUrlLookerProcessor())
>> >>> >> > .to("direct:endPointB")*
>> >>> >> >
>> >>> >> > *from("direct:endpointB")
>> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>> >>> >> > .process(myUrlLookerProcessor())
>> >>> >> > .to("direct:endPointC")*
>> >>> >> >
>> >>> >> > *
>> >>> >> > from("direct:endPointC")
>> >>> >> > .to("xquery:response.xml");*
>> >>> >> >
>> >>> >> > *from("direct:letter")
>> >>> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
>> >>> >> >
>> >>> >> >
>> >>> >> >
>> >>> >> > Thanks in advance for help.
>> >>> >> >
>> >>> >> > Nasmo
>> >>> >> >
>> >>> >> >
>> >>> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <
>> claus.ibsen@gmail.com>
>> >>> >> wrote:
>> >>> >> >
>> >>> >> >> Hi
>> >>> >> >>
>> >>> >> >> BTW You can also always just use a Processor and implement the
>> >>> >> >> failover logic yourself as pure Java with try .. catch and use
>> the
>> >>> >> >> ProducerTemplate to send the exchange to the endpoint based on
>> the
>> >>> >> >> URI.
>> >>> >> >>
>> >>> >> >> Something like
>> >>> >> >> ProducerTemplate template = // get it from CamelContext and get
>> it
>> >>> once
>> >>> >> >> List<Strig> uris = ...
>> >>> >> >>
>> >>> >> >> for (String uri : uris) {
>> >>> >> >> try {
>> >>> >> >> template.send(uri, exchange);
>> >>> >> >> } catch (Exception e) {
>> >>> >> >> exchange.setExceptipn(e);
>> >>> >> >> }
>> >>> >> >> if (exchange.getException() == null) {
>> >>> >> >> return;
>> >>> >> >> }
>> >>> >> >> }
>> >>> >> >>
>> >>> >> >>
>> >>> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <
>> claus.ibsen@gmail.com>
>> >>> >> >> wrote:
>> >>> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
>> >>> nasmo2009@googlemail.com
>> >>> >> >
>> >>> >> >> wrote:
>> >>> >> >> >> Thanks Claus for your quick answer.
>> >>> >> >> >>
>> >>> >> >> >> I downloaded the source of camel 2.0 and I looked at the
>> >>> >> >> >> FailOverLoadBalancer class. I think that this could answer to
>> my
>> >>> >> >> question.
>> >>> >> >> >> I've tried to adapt the code to my requirement but I have some
>> >>> >> questions
>> >>> >> >> >> about the list of processors used in this class :
>> >>> >> >> >>
>> >>> >> >> >> 1. I don't know How to create or initialize the processors
>> used
>> >>> for
>> >>> >> >> >> balancing user requests ?
>> >>> >> >> >>
>> >>> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
>> >>> >> >> >>
>> >>> >> >> >> 3. Whait is the syntaxe (maybe something like new
>> >>> >> Processor(myHttpURL))
>> >>> >> >> > Hi
>> >>> >> >> >
>> >>> >> >> > Yeah there is no nice DSL support for it and the loadbalance()
>> DSL
>> >>> >> >> > does not have a nice support for custom load balancer.
>> >>> >> >> > So that is something we might need to improve in the future. I
>> have
>> >>> to
>> >>> >> >> > remember this thread.
>> >>> >> >> >
>> >>> >> >> > So what you basically have to do is to add your custom load
>> >>> balancer
>> >>> >> >> > as a processor, so use the process() DSL.
>> >>> >> >> >
>> >>> >> >> > And your custom fail over loadbalancer can accept a list of
>> >>> endpoints
>> >>> >> >> > to select among. You can wrap an endpoint to a processor
>> >>> >> >> > with the SendToProcessor.
>> >>> >> >> >
>> >>> >> >> > Something like this
>> >>> >> >> >
>> >>> >> >> > MyFailover my = new MyFailoverProcessor()l;
>> >>> >> >> > my.addEndpoint("foo");
>> >>> >> >> > my.addEndpoint("bar");
>> >>> >> >> >
>> >>> >> >> >
>> >>> >> >> > And in the route DSL you just route to your processor
>> >>> >> >> > from(x).process(my);
>> >>> >> >> >
>> >>> >> >> > And in the addEndpoint method you add the endpoint by wrapping
>> it
>> >>> with
>> >>> >> >> > a SendToProcessor so you can add it to the LoadBalancerSupport
>> >>> class.
>> >>> >> >> >
>> >>> >> >> > See how it goes and ask again tomorrow when I am back in the
>> office
>> >>> >> >> > and can better work. As I sit now with the laptop in the living
>> >>> room.
>> >>> >> >> >
>> >>> >> >> >
>> >>> >> >> >>
>> >>> >> >> >> Thanks for help
>> >>> >> >> >>
>> >>> >> >> >>
>> >>> >> >> >>
>> >>> >> >> >>
>> >>> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
>> >>> claus.ibsen@gmail.com
>> >>> >> >
>> >>> >> >> wrote:
>> >>> >> >> >>
>> >>> >> >> >>> Hi
>> >>> >> >> >>>
>> >>> >> >> >>> There are load balancers with Camel
>> >>> >> >> >>> http://camel.apache.org/load-balancer.html
>> >>> >> >> >>>
>> >>> >> >> >>> And there is a failover load balancer as well that can do a
>> >>> simple
>> >>> >> try
>> >>> >> >> >>> the next endpoint until success kinda style.
>> >>> >> >> >>> Its a bit primitive at the moment and we would like to
>> improve
>> >>> that
>> >>> >> in
>> >>> >> >> >>> the future.
>> >>> >> >> >>>
>> >>> >> >> >>> But it allows you to implement your own load balancer and do
>> your
>> >>> >> >> >>> strategy how you like it.
>> >>> >> >> >>>
>> >>> >> >> >>> Any feedback for features that could be needed for a more
>> >>> advanced
>> >>> >> >> >>> failover loadbalancer is much welcome.
>> >>> >> >> >>>
>> >>> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But
>> you
>> >>> can
>> >>> >> >> >>> check the source code for 2.0 and create your own kinda to
>> use in
>> >>> >> 1.x.
>> >>> >> >> >>>
>> >>> >> >> >>>
>> >>> >> >>
>> >>> >>
>> >>>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>> >>> >> >> >>>
>> >>> >> >> >>>
>> >>> >> >> >>>
>> >>> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
>> >>> >> nasmo2009@googlemail.com
>> >>> >> >> >
>> >>> >> >> >>> wrote:
>> >>> >> >> >>> > Hi,
>> >>> >> >> >>> >
>> >>> >> >> >>> > I would like to implement the following route with Camel
>> 1.6 :
>> >>> >> >> >>> >
>> >>> >> >> >>> > from("direct:endpointA")
>> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
>> http://myAddressA")
>> >>> >> >> >>> > .to("http://xxxxxx")
>> >>> >> >> >>> > .to("direct:endPointB")
>> >>> >> >> >>> >
>> >>> >> >> >>> > from("direct:endpointB")
>> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
>> http://myAddressB")
>> >>> >> >> >>> > .to("http://xxxxxx")
>> >>> >> >> >>> > .to("direct:endPointC")
>> >>> >> >> >>> >
>> >>> >> >> >>> > from("direct:endPointC")
>> >>> >> >> >>> > .to("xquery:response.xml");
>> >>> >> >> >>> >
>> >>> >> >> >>> > This route works fine if both URLs : http://myAddressA and
>> >>> >> >> >>> > http://myAddressBare accessible and no error occurs during
>> the
>> >>> >> >> >>> > invocation.
>> >>> >> >> >>> > Unfortunately, sometimes these services become unreachable
>> and
>> >>> I
>> >>> >> >> would
>> >>> >> >> >>> like
>> >>> >> >> >>> > to try other URLs until getting valid answer:
>> >>> >> >> >>> >
>> >>> >> >> >>> > If an exception happens when calling the URL
>> http:/:myAddressA,
>> >>> I
>> >>> >> >> would
>> >>> >> >> >>> like
>> >>> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until
>> >>> getting
>> >>> >> >> valid
>> >>> >> >> >>> > HTTP response.
>> >>> >> >> >>> > The same thing with myAddressB ==> myAddressB1,
>> myAddressB2,
>> >>> ...
>> >>> >> >> >>> >
>> >>> >> >> >>> > With java this could be simply coded like following :
>> >>> >> >> >>> >
>> >>> >> >> >>> > try
>> >>> >> >> >>> > {
>> >>> >> >> >>> > call_http(myAddressA)
>> >>> >> >> >>> > }
>> >>> >> >> >>> > catch(Throwable th)
>> >>> >> >> >>> > {
>> >>> >> >> >>> > try
>> >>> >> >> >>> > {
>> >>> >> >> >>> > call_http(myAddressA1)
>> >>> >> >> >>> > }
>> >>> >> >> >>> > catch(Exception x)
>> >>> >> >> >>> > {
>> >>> >> >> >>> > //Call addressA2
>> >>> >> >> >>> > ....
>> >>> >> >> >>> > }
>> >>> >> >> >>> > }
>> >>> >> >> >>> >
>> >>> >> >> >>> > I've tried the onException() mechanism and the
>> >>> deadLetterChannel
>> >>> >> >> >>> processor
>> >>> >> >> >>> > but I never get working my route.
>> >>> >> >> >>> >
>> >>> >> >> >>>
>> >>> >> >> >>>
>> >>> >> >> >>>
>> >>> >> >> >>> --
>> >>> >> >> >>> Claus Ibsen
>> >>> >> >> >>> Apache Camel Committer
>> >>> >> >> >>>
>> >>> >> >> >>> Open Source Integration: http://fusesource.com
>> >>> >> >> >>> Blog: http://davsclaus.blogspot.com/
>> >>> >> >> >>> Twitter: http://twitter.com/davsclaus
>> >>> >> >> >>>
>> >>> >> >> >>
>> >>> >> >> >
>> >>> >> >> >
>> >>> >> >> >
>> >>> >> >> > --
>> >>> >> >> > Claus Ibsen
>> >>> >> >> > Apache Camel Committer
>> >>> >> >> >
>> >>> >> >> > Open Source Integration: http://fusesource.com
>> >>> >> >> > Blog: http://davsclaus.blogspot.com/
>> >>> >> >> > Twitter: http://twitter.com/davsclaus
>> >>> >> >> >
>> >>> >> >>
>> >>> >> >>
>> >>> >> >>
>> >>> >> >> --
>> >>> >> >> Claus Ibsen
>> >>> >> >> Apache Camel Committer
>> >>> >> >>
>> >>> >> >> Open Source Integration: http://fusesource.com
>> >>> >> >> Blog: http://davsclaus.blogspot.com/
>> >>> >> >> Twitter: http://twitter.com/davsclaus
>> >>> >> >>
>> >>> >> >
>> >>> >>
>> >>> >>
>> >>> >>
>> >>> >> --
>> >>> >> Claus Ibsen
>> >>> >> Apache Camel Committer
>> >>> >>
>> >>> >> Open Source Integration: http://fusesource.com
>> >>> >> Blog: http://davsclaus.blogspot.com/
>> >>> >> Twitter: http://twitter.com/davsclaus
>> >>> >>
>> >>> >
>> >>>
>> >>>
>> >>>
>> >>> --
>> >>> Claus Ibsen
>> >>> Apache Camel Committer
>> >>>
>> >>> Open Source Integration: http://fusesource.com
>> >>> Blog: http://davsclaus.blogspot.com/
>> >>> Twitter: http://twitter.com/davsclaus
>> >>>
>> >>
>> >
>> >
>> >
>> > --
>> > Claus Ibsen
>> > Apache Camel Committer
>> >
>> > Open Source Integration: http://fusesource.com
>> > Blog: http://davsclaus.blogspot.com/
>> > Twitter: http://twitter.com/davsclaus
>> >
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Nasim Anza <na...@googlemail.com>.
Thanks Claus for your help.
Actually the problem I got is not related to the FailOverProcessor mechanism
but in the global route:
I would like that the result of a given HTTP endoint goes into another HTTP
endpoint.
For example the result of HTTP endpointA will be redirected to the HTTP
endpoint B.... etc
I've pasted my route and my FailOver Processor on pastbin URL :
http://mmo.pastebin.com/m7160e173
Please let me know if I have any error or mistake in the code.
Note : the appliA1, appliA2, .appliX are webservices that return valid SOAP
XMLs
Thanks a lot for any help
Nasmo
On Sat, May 16, 2009 at 4:52 PM, Claus Ibsen <cl...@gmail.com> wrote:
> Hi
>
> I have created an example how to do your own custom processor as
> failover. Its based on an unit test and the code is here:
>
>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/issues/CustomFailveOverProcessor.java
>
> The code is based on Camel 2.0, but you can do the same in Camel 1.x.
>
>
> On Sat, May 16, 2009 at 4:37 PM, Claus Ibsen <cl...@gmail.com>
> wrote:
> > Hi
> >
> > Sometimes its easier to read the code when there is quite a bit if you
> > paste it using http://pastebin.com/ or the likes.
> >
> >
> >
> > On Fri, May 15, 2009 at 5:44 PM, Nasim Anza <na...@googlemail.com>
> wrote:
> >> Thanks Claus for answers.
> >>
> >> My processor is working fine and it finds the URL to invoke but the
> problem
> >> is on the last step : the next endpoint is not called with right XML
> input :
> >>
> >> Just to explain my actual problem :
> >> Let's assume that my route is :
> >>
> >> from("direct:endpointA")
> >> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >> .process(myFailOverProcessor("direct:endpointB")); //forward HTTP
> response
> >> to the direct:endpointB
> >>
> >> from("direct:endpointB")
> >> .to("log:display the XML input"); //just display it to compare XMLs
> >>
> >> The displayed XML on the "log:..." endpoint doesn't correspond to the
> http
> >> response of "http://myAddressA"...
> >>
> >> Here is my Processor class :
> >>
> >>
> >> public class FailOverProcessor implements Processor{
> >>
> >> public FailOverProcessor(String endpoint) {
> >> this.endpoint=endpoint;
> >> }
> >>
> >> public void process(Exchange exchange) throws Exception {
> >> Exchange out = null;
> >> int index = 0;
> >> out = processExchange(exchange);
> >>
> >> while (exchange.getException() != null){
> >>
> >> //reset the exchange exceptiuon
> >> exchange.setException(null);
> >>
> >> if (index++ < 4 ) {
> >> System.out.println(index+" : processExchange .....");
> >>
> >> out = processExchange(exchange);
> >> }
> >> }
> >>
> >> if(endpoint != null)
> >> {
> >> ProducerTemplate<Exchange> template =
> >> exchange.getContext().createProducerTemplate();
> >> if(out != null)
> >> {
> >>
> >> Message responseOut = exchange.getOut();
> >> int responseCode =
> >> responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE, Integer.class);
> >> System.out.println("\n\n Response out \\n" + responseCode +
> >> responseOut.getBody(String.class));
> >>
> >> //I've tried all the these calls but no valid response
> >> // template.send(endpoint, exchange.getOut().getExchange());
> >> // template.sendBody(endpoint, exchange.getBody());
> >> template.send(endpoint, exchange);
> >> }
> >> }
> >> }
> >>
> >> private Exchange processExchange(Exchange exchange) {
> >>
> >> Exchange out = null;
> >>
> >> try {
> >>
> >> //Define the strategy to use for processing message
> >> String uri =
> >>
> exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
> >> System.out.println("Current URI ==> "+uri);
> >>
> >> //just for test
> >> if(uri.equalsIgnoreCase("http://myAddressA"))
> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> http://serverA/appli1");
> >> else if(uri.equalsIgnoreCase("http://myAddressB"))
> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> http://serverB/appli2");
> >> else
> >> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> >> http://serverC/error");
> >>
> >> ProducerTemplate<Exchange> template =
> >> exchange.getContext().createProducerTemplate();
> >>
> >> out = template.send(uri, exchange);
> >>
> >> } catch (Throwable th) {
> >> //Set the thrown exception
> >> exchange.setException(th.getCause());
> >> }
> >>
> >> return out;
> >> }
> >> }
> >>
> >> Thanks for your help
> >> Nasmo
> >>
> >>
> >>
> >>
> >> On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <cl...@gmail.com>
> wrote:
> >>
> >>> You need to test the exchange afterwards if there was an exception.
> >>>
> >>> template.send(endpoint, exchange);
> >>> if (exchange.getException() != null) {
> >>> // ops it failed so call the next URI as fallback
> >>> ...
> >>> }
> >>>
> >>>
> >>>
> >>>
> >>> >
> >>> > Unfortunately this doesn't change anything on the SMIX console. I
> have
> >>> the
> >>> > same error :
> >>> >
> >>> > FATAL - DeadLetterChannel - Failed delivery for
> exchangeId:
> >>> > ID-ROME/1982-1242375956166/0-
> >>> > Handled by the failure
> >>> processor:sendTo(Endpoint[direct:deadLetterChannel])
> >>> >
> >>> > Thanks for help
> >>> >
> >>> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <claus.ibsen@gmail.com
> >
> >>> wrote:
> >>> >
> >>> >> Hi
> >>> >>
> >>> >> You should *not* route after your custom failover processor. You
> >>> >> custom failover processor should be the end of the route (eg no more
> >>> >> .to after your processor).
> >>> >>
> >>> >>
> >>> >>
> >>> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <
> nasmo2009@googlemail.com>
> >>> >> wrote:
> >>> >> > Hi,
> >>> >> >
> >>> >> > I’ve tried this solution:
> >>> >> > I started by developing a processor that loops on URIs until
> getting a
> >>> >> valid
> >>> >> > answer.
> >>> >> > The only problem is my route is interrupted at the end of the
> first
> >>> >> > processing, so no way to pass from first block (addressA) to next
> >>> block
> >>> >> > (AddressB).
> >>> >> >
> >>> >> > The process() method loops on all URI until getting the valid URI.
> >>> This
> >>> >> > works but after that I got a fatal error and the route flow was
> >>> >> interrupted.
> >>> >> > Below the error I got on ServiceMix console:
> >>> >> >
> >>> >> > ----------------
> >>> >> >
> >>> >> > FATAL - DeadLetterChannel - Failed delivery for
> >>> exchangeId:
> >>> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
> >>> >> > sendTo(Endpoint[direct:deadLetterChannel])
> >>> >> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
> >>> >> doIntercept
> >>> >> > INFO: Interceptor has thrown exception, unwinding now
> >>> >> > org.apache.xerces.dom.TextImpl
> >>> >> >
> >>> >> > ----------------
> >>> >> >
> >>> >> > Here is my Camel route:
> >>> >> >
> >>> >> > * //Declare Deadletter processor*
> >>> >> >
> >>> >> >
> >>> >>
> >>>
> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
> >>> >> > *
> >>> >> >
> >>> >> > * //Declare global exception*
> >>> >> >
> >>> >> > *onException(Exception.class).maximumRedeliveries(5) //5 : because
> I
> >>> have
> >>> >> 5
> >>> >> > address maximum to call*
> >>> >> >
> >>> >> > *final Processor myprocessor() = new Processor(Exchange exchange)
> >>> throws
> >>> >> > Exception{*
> >>> >> > **
> >>> >> >
> >>> >> > *ProducerTemplate<Exchange> template
> >>> >> > exchange.getContext().createProducerTemplate();
> >>> >> > String uri =
> >>> >> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
> >>> >> > *
> >>> >> >
> >>> >> > *//This method returns the valid list depending on the current
> http
> >>> URI*
> >>> >> >
> >>> >> > *List<Strig> uris = getUriList(uri);*
> >>> >> >
> >>> >> > *for (String uri : uris) {*
> >>> >> >
> >>> >> > * try {*
> >>> >> >
> >>> >> > * template.send(uri, exchange);*
> >>> >> >
> >>> >> > * } catch (Exception e) {*
> >>> >> >
> >>> >> > * exchange.setExceptipn(e);*
> >>> >> >
> >>> >> > * }*
> >>> >> >
> >>> >> > * if (exchange.getException() == null) {*
> >>> >> >
> >>> >> > * return;
> >>> >> > }
> >>> >> > }
> >>> >> > }*
> >>> >> >
> >>> >> > * *
> >>> >> >
> >>> >> > *from("direct:endpointA")
> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >>> >> > .process(myUrlLookerProcessor())
> >>> >> > .to("direct:endPointB")*
> >>> >> >
> >>> >> > *from("direct:endpointB")
> >>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> >>> >> > .process(myUrlLookerProcessor())
> >>> >> > .to("direct:endPointC")*
> >>> >> >
> >>> >> > *
> >>> >> > from("direct:endPointC")
> >>> >> > .to("xquery:response.xml");*
> >>> >> >
> >>> >> > *from("direct:letter")
> >>> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
> >>> >> >
> >>> >> >
> >>> >> >
> >>> >> > Thanks in advance for help.
> >>> >> >
> >>> >> > Nasmo
> >>> >> >
> >>> >> >
> >>> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <
> claus.ibsen@gmail.com>
> >>> >> wrote:
> >>> >> >
> >>> >> >> Hi
> >>> >> >>
> >>> >> >> BTW You can also always just use a Processor and implement the
> >>> >> >> failover logic yourself as pure Java with try .. catch and use
> the
> >>> >> >> ProducerTemplate to send the exchange to the endpoint based on
> the
> >>> >> >> URI.
> >>> >> >>
> >>> >> >> Something like
> >>> >> >> ProducerTemplate template = // get it from CamelContext and get
> it
> >>> once
> >>> >> >> List<Strig> uris = ...
> >>> >> >>
> >>> >> >> for (String uri : uris) {
> >>> >> >> try {
> >>> >> >> template.send(uri, exchange);
> >>> >> >> } catch (Exception e) {
> >>> >> >> exchange.setExceptipn(e);
> >>> >> >> }
> >>> >> >> if (exchange.getException() == null) {
> >>> >> >> return;
> >>> >> >> }
> >>> >> >> }
> >>> >> >>
> >>> >> >>
> >>> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <
> claus.ibsen@gmail.com>
> >>> >> >> wrote:
> >>> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
> >>> nasmo2009@googlemail.com
> >>> >> >
> >>> >> >> wrote:
> >>> >> >> >> Thanks Claus for your quick answer.
> >>> >> >> >>
> >>> >> >> >> I downloaded the source of camel 2.0 and I looked at the
> >>> >> >> >> FailOverLoadBalancer class. I think that this could answer to
> my
> >>> >> >> question.
> >>> >> >> >> I've tried to adapt the code to my requirement but I have some
> >>> >> questions
> >>> >> >> >> about the list of processors used in this class :
> >>> >> >> >>
> >>> >> >> >> 1. I don't know How to create or initialize the processors
> used
> >>> for
> >>> >> >> >> balancing user requests ?
> >>> >> >> >>
> >>> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
> >>> >> >> >>
> >>> >> >> >> 3. Whait is the syntaxe (maybe something like new
> >>> >> Processor(myHttpURL))
> >>> >> >> > Hi
> >>> >> >> >
> >>> >> >> > Yeah there is no nice DSL support for it and the loadbalance()
> DSL
> >>> >> >> > does not have a nice support for custom load balancer.
> >>> >> >> > So that is something we might need to improve in the future. I
> have
> >>> to
> >>> >> >> > remember this thread.
> >>> >> >> >
> >>> >> >> > So what you basically have to do is to add your custom load
> >>> balancer
> >>> >> >> > as a processor, so use the process() DSL.
> >>> >> >> >
> >>> >> >> > And your custom fail over loadbalancer can accept a list of
> >>> endpoints
> >>> >> >> > to select among. You can wrap an endpoint to a processor
> >>> >> >> > with the SendToProcessor.
> >>> >> >> >
> >>> >> >> > Something like this
> >>> >> >> >
> >>> >> >> > MyFailover my = new MyFailoverProcessor()l;
> >>> >> >> > my.addEndpoint("foo");
> >>> >> >> > my.addEndpoint("bar");
> >>> >> >> >
> >>> >> >> >
> >>> >> >> > And in the route DSL you just route to your processor
> >>> >> >> > from(x).process(my);
> >>> >> >> >
> >>> >> >> > And in the addEndpoint method you add the endpoint by wrapping
> it
> >>> with
> >>> >> >> > a SendToProcessor so you can add it to the LoadBalancerSupport
> >>> class.
> >>> >> >> >
> >>> >> >> > See how it goes and ask again tomorrow when I am back in the
> office
> >>> >> >> > and can better work. As I sit now with the laptop in the living
> >>> room.
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >>
> >>> >> >> >> Thanks for help
> >>> >> >> >>
> >>> >> >> >>
> >>> >> >> >>
> >>> >> >> >>
> >>> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
> >>> claus.ibsen@gmail.com
> >>> >> >
> >>> >> >> wrote:
> >>> >> >> >>
> >>> >> >> >>> Hi
> >>> >> >> >>>
> >>> >> >> >>> There are load balancers with Camel
> >>> >> >> >>> http://camel.apache.org/load-balancer.html
> >>> >> >> >>>
> >>> >> >> >>> And there is a failover load balancer as well that can do a
> >>> simple
> >>> >> try
> >>> >> >> >>> the next endpoint until success kinda style.
> >>> >> >> >>> Its a bit primitive at the moment and we would like to
> improve
> >>> that
> >>> >> in
> >>> >> >> >>> the future.
> >>> >> >> >>>
> >>> >> >> >>> But it allows you to implement your own load balancer and do
> your
> >>> >> >> >>> strategy how you like it.
> >>> >> >> >>>
> >>> >> >> >>> Any feedback for features that could be needed for a more
> >>> advanced
> >>> >> >> >>> failover loadbalancer is much welcome.
> >>> >> >> >>>
> >>> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But
> you
> >>> can
> >>> >> >> >>> check the source code for 2.0 and create your own kinda to
> use in
> >>> >> 1.x.
> >>> >> >> >>>
> >>> >> >> >>>
> >>> >> >>
> >>> >>
> >>>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
> >>> >> >> >>>
> >>> >> >> >>>
> >>> >> >> >>>
> >>> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
> >>> >> nasmo2009@googlemail.com
> >>> >> >> >
> >>> >> >> >>> wrote:
> >>> >> >> >>> > Hi,
> >>> >> >> >>> >
> >>> >> >> >>> > I would like to implement the following route with Camel
> 1.6 :
> >>> >> >> >>> >
> >>> >> >> >>> > from("direct:endpointA")
> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
> http://myAddressA")
> >>> >> >> >>> > .to("http://xxxxxx")
> >>> >> >> >>> > .to("direct:endPointB")
> >>> >> >> >>> >
> >>> >> >> >>> > from("direct:endpointB")
> >>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("
> http://myAddressB")
> >>> >> >> >>> > .to("http://xxxxxx")
> >>> >> >> >>> > .to("direct:endPointC")
> >>> >> >> >>> >
> >>> >> >> >>> > from("direct:endPointC")
> >>> >> >> >>> > .to("xquery:response.xml");
> >>> >> >> >>> >
> >>> >> >> >>> > This route works fine if both URLs : http://myAddressA and
> >>> >> >> >>> > http://myAddressBare accessible and no error occurs during
> the
> >>> >> >> >>> > invocation.
> >>> >> >> >>> > Unfortunately, sometimes these services become unreachable
> and
> >>> I
> >>> >> >> would
> >>> >> >> >>> like
> >>> >> >> >>> > to try other URLs until getting valid answer:
> >>> >> >> >>> >
> >>> >> >> >>> > If an exception happens when calling the URL
> http:/:myAddressA,
> >>> I
> >>> >> >> would
> >>> >> >> >>> like
> >>> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until
> >>> getting
> >>> >> >> valid
> >>> >> >> >>> > HTTP response.
> >>> >> >> >>> > The same thing with myAddressB ==> myAddressB1,
> myAddressB2,
> >>> ...
> >>> >> >> >>> >
> >>> >> >> >>> > With java this could be simply coded like following :
> >>> >> >> >>> >
> >>> >> >> >>> > try
> >>> >> >> >>> > {
> >>> >> >> >>> > call_http(myAddressA)
> >>> >> >> >>> > }
> >>> >> >> >>> > catch(Throwable th)
> >>> >> >> >>> > {
> >>> >> >> >>> > try
> >>> >> >> >>> > {
> >>> >> >> >>> > call_http(myAddressA1)
> >>> >> >> >>> > }
> >>> >> >> >>> > catch(Exception x)
> >>> >> >> >>> > {
> >>> >> >> >>> > //Call addressA2
> >>> >> >> >>> > ....
> >>> >> >> >>> > }
> >>> >> >> >>> > }
> >>> >> >> >>> >
> >>> >> >> >>> > I've tried the onException() mechanism and the
> >>> deadLetterChannel
> >>> >> >> >>> processor
> >>> >> >> >>> > but I never get working my route.
> >>> >> >> >>> >
> >>> >> >> >>>
> >>> >> >> >>>
> >>> >> >> >>>
> >>> >> >> >>> --
> >>> >> >> >>> Claus Ibsen
> >>> >> >> >>> Apache Camel Committer
> >>> >> >> >>>
> >>> >> >> >>> Open Source Integration: http://fusesource.com
> >>> >> >> >>> Blog: http://davsclaus.blogspot.com/
> >>> >> >> >>> Twitter: http://twitter.com/davsclaus
> >>> >> >> >>>
> >>> >> >> >>
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> >>> >> >> > --
> >>> >> >> > Claus Ibsen
> >>> >> >> > Apache Camel Committer
> >>> >> >> >
> >>> >> >> > Open Source Integration: http://fusesource.com
> >>> >> >> > Blog: http://davsclaus.blogspot.com/
> >>> >> >> > Twitter: http://twitter.com/davsclaus
> >>> >> >> >
> >>> >> >>
> >>> >> >>
> >>> >> >>
> >>> >> >> --
> >>> >> >> Claus Ibsen
> >>> >> >> Apache Camel Committer
> >>> >> >>
> >>> >> >> Open Source Integration: http://fusesource.com
> >>> >> >> Blog: http://davsclaus.blogspot.com/
> >>> >> >> Twitter: http://twitter.com/davsclaus
> >>> >> >>
> >>> >> >
> >>> >>
> >>> >>
> >>> >>
> >>> >> --
> >>> >> Claus Ibsen
> >>> >> Apache Camel Committer
> >>> >>
> >>> >> Open Source Integration: http://fusesource.com
> >>> >> Blog: http://davsclaus.blogspot.com/
> >>> >> Twitter: http://twitter.com/davsclaus
> >>> >>
> >>> >
> >>>
> >>>
> >>>
> >>> --
> >>> Claus Ibsen
> >>> Apache Camel Committer
> >>>
> >>> Open Source Integration: http://fusesource.com
> >>> Blog: http://davsclaus.blogspot.com/
> >>> Twitter: http://twitter.com/davsclaus
> >>>
> >>
> >
> >
> >
> > --
> > Claus Ibsen
> > Apache Camel Committer
> >
> > Open Source Integration: http://fusesource.com
> > Blog: http://davsclaus.blogspot.com/
> > Twitter: http://twitter.com/davsclaus
> >
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
Hi
I have created an example how to do your own custom processor as
failover. Its based on an unit test and the code is here:
https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/issues/CustomFailveOverProcessor.java
The code is based on Camel 2.0, but you can do the same in Camel 1.x.
On Sat, May 16, 2009 at 4:37 PM, Claus Ibsen <cl...@gmail.com> wrote:
> Hi
>
> Sometimes its easier to read the code when there is quite a bit if you
> paste it using http://pastebin.com/ or the likes.
>
>
>
> On Fri, May 15, 2009 at 5:44 PM, Nasim Anza <na...@googlemail.com> wrote:
>> Thanks Claus for answers.
>>
>> My processor is working fine and it finds the URL to invoke but the problem
>> is on the last step : the next endpoint is not called with right XML input :
>>
>> Just to explain my actual problem :
>> Let's assume that my route is :
>>
>> from("direct:endpointA")
>> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> .process(myFailOverProcessor("direct:endpointB")); //forward HTTP response
>> to the direct:endpointB
>>
>> from("direct:endpointB")
>> .to("log:display the XML input"); //just display it to compare XMLs
>>
>> The displayed XML on the "log:..." endpoint doesn't correspond to the http
>> response of "http://myAddressA"...
>>
>> Here is my Processor class :
>>
>>
>> public class FailOverProcessor implements Processor{
>>
>> public FailOverProcessor(String endpoint) {
>> this.endpoint=endpoint;
>> }
>>
>> public void process(Exchange exchange) throws Exception {
>> Exchange out = null;
>> int index = 0;
>> out = processExchange(exchange);
>>
>> while (exchange.getException() != null){
>>
>> //reset the exchange exceptiuon
>> exchange.setException(null);
>>
>> if (index++ < 4 ) {
>> System.out.println(index+" : processExchange .....");
>>
>> out = processExchange(exchange);
>> }
>> }
>>
>> if(endpoint != null)
>> {
>> ProducerTemplate<Exchange> template =
>> exchange.getContext().createProducerTemplate();
>> if(out != null)
>> {
>>
>> Message responseOut = exchange.getOut();
>> int responseCode =
>> responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE, Integer.class);
>> System.out.println("\n\n Response out \\n" + responseCode +
>> responseOut.getBody(String.class));
>>
>> //I've tried all the these calls but no valid response
>> // template.send(endpoint, exchange.getOut().getExchange());
>> // template.sendBody(endpoint, exchange.getBody());
>> template.send(endpoint, exchange);
>> }
>> }
>> }
>>
>> private Exchange processExchange(Exchange exchange) {
>>
>> Exchange out = null;
>>
>> try {
>>
>> //Define the strategy to use for processing message
>> String uri =
>> exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
>> System.out.println("Current URI ==> "+uri);
>>
>> //just for test
>> if(uri.equalsIgnoreCase("http://myAddressA"))
>> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> http://serverA/appli1");
>> else if(uri.equalsIgnoreCase("http://myAddressB"))
>> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> http://serverB/appli2");
>> else
>> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
>> http://serverC/error");
>>
>> ProducerTemplate<Exchange> template =
>> exchange.getContext().createProducerTemplate();
>>
>> out = template.send(uri, exchange);
>>
>> } catch (Throwable th) {
>> //Set the thrown exception
>> exchange.setException(th.getCause());
>> }
>>
>> return out;
>> }
>> }
>>
>> Thanks for your help
>> Nasmo
>>
>>
>>
>>
>> On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <cl...@gmail.com> wrote:
>>
>>> You need to test the exchange afterwards if there was an exception.
>>>
>>> template.send(endpoint, exchange);
>>> if (exchange.getException() != null) {
>>> // ops it failed so call the next URI as fallback
>>> ...
>>> }
>>>
>>>
>>>
>>>
>>> >
>>> > Unfortunately this doesn't change anything on the SMIX console. I have
>>> the
>>> > same error :
>>> >
>>> > FATAL - DeadLetterChannel - Failed delivery for exchangeId:
>>> > ID-ROME/1982-1242375956166/0-
>>> > Handled by the failure
>>> processor:sendTo(Endpoint[direct:deadLetterChannel])
>>> >
>>> > Thanks for help
>>> >
>>> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <cl...@gmail.com>
>>> wrote:
>>> >
>>> >> Hi
>>> >>
>>> >> You should *not* route after your custom failover processor. You
>>> >> custom failover processor should be the end of the route (eg no more
>>> >> .to after your processor).
>>> >>
>>> >>
>>> >>
>>> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <na...@googlemail.com>
>>> >> wrote:
>>> >> > Hi,
>>> >> >
>>> >> > I’ve tried this solution:
>>> >> > I started by developing a processor that loops on URIs until getting a
>>> >> valid
>>> >> > answer.
>>> >> > The only problem is my route is interrupted at the end of the first
>>> >> > processing, so no way to pass from first block (addressA) to next
>>> block
>>> >> > (AddressB).
>>> >> >
>>> >> > The process() method loops on all URI until getting the valid URI.
>>> This
>>> >> > works but after that I got a fatal error and the route flow was
>>> >> interrupted.
>>> >> > Below the error I got on ServiceMix console:
>>> >> >
>>> >> > ----------------
>>> >> >
>>> >> > FATAL - DeadLetterChannel - Failed delivery for
>>> exchangeId:
>>> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
>>> >> > sendTo(Endpoint[direct:deadLetterChannel])
>>> >> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
>>> >> doIntercept
>>> >> > INFO: Interceptor has thrown exception, unwinding now
>>> >> > org.apache.xerces.dom.TextImpl
>>> >> >
>>> >> > ----------------
>>> >> >
>>> >> > Here is my Camel route:
>>> >> >
>>> >> > * //Declare Deadletter processor*
>>> >> >
>>> >> >
>>> >>
>>> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
>>> >> > *
>>> >> >
>>> >> > * //Declare global exception*
>>> >> >
>>> >> > *onException(Exception.class).maximumRedeliveries(5) //5 : because I
>>> have
>>> >> 5
>>> >> > address maximum to call*
>>> >> >
>>> >> > *final Processor myprocessor() = new Processor(Exchange exchange)
>>> throws
>>> >> > Exception{*
>>> >> > **
>>> >> >
>>> >> > *ProducerTemplate<Exchange> template
>>> >> > exchange.getContext().createProducerTemplate();
>>> >> > String uri =
>>> >> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
>>> >> > *
>>> >> >
>>> >> > *//This method returns the valid list depending on the current http
>>> URI*
>>> >> >
>>> >> > *List<Strig> uris = getUriList(uri);*
>>> >> >
>>> >> > *for (String uri : uris) {*
>>> >> >
>>> >> > * try {*
>>> >> >
>>> >> > * template.send(uri, exchange);*
>>> >> >
>>> >> > * } catch (Exception e) {*
>>> >> >
>>> >> > * exchange.setExceptipn(e);*
>>> >> >
>>> >> > * }*
>>> >> >
>>> >> > * if (exchange.getException() == null) {*
>>> >> >
>>> >> > * return;
>>> >> > }
>>> >> > }
>>> >> > }*
>>> >> >
>>> >> > * *
>>> >> >
>>> >> > *from("direct:endpointA")
>>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>>> >> > .process(myUrlLookerProcessor())
>>> >> > .to("direct:endPointB")*
>>> >> >
>>> >> > *from("direct:endpointB")
>>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>>> >> > .process(myUrlLookerProcessor())
>>> >> > .to("direct:endPointC")*
>>> >> >
>>> >> > *
>>> >> > from("direct:endPointC")
>>> >> > .to("xquery:response.xml");*
>>> >> >
>>> >> > *from("direct:letter")
>>> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
>>> >> >
>>> >> >
>>> >> >
>>> >> > Thanks in advance for help.
>>> >> >
>>> >> > Nasmo
>>> >> >
>>> >> >
>>> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <cl...@gmail.com>
>>> >> wrote:
>>> >> >
>>> >> >> Hi
>>> >> >>
>>> >> >> BTW You can also always just use a Processor and implement the
>>> >> >> failover logic yourself as pure Java with try .. catch and use the
>>> >> >> ProducerTemplate to send the exchange to the endpoint based on the
>>> >> >> URI.
>>> >> >>
>>> >> >> Something like
>>> >> >> ProducerTemplate template = // get it from CamelContext and get it
>>> once
>>> >> >> List<Strig> uris = ...
>>> >> >>
>>> >> >> for (String uri : uris) {
>>> >> >> try {
>>> >> >> template.send(uri, exchange);
>>> >> >> } catch (Exception e) {
>>> >> >> exchange.setExceptipn(e);
>>> >> >> }
>>> >> >> if (exchange.getException() == null) {
>>> >> >> return;
>>> >> >> }
>>> >> >> }
>>> >> >>
>>> >> >>
>>> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <cl...@gmail.com>
>>> >> >> wrote:
>>> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
>>> nasmo2009@googlemail.com
>>> >> >
>>> >> >> wrote:
>>> >> >> >> Thanks Claus for your quick answer.
>>> >> >> >>
>>> >> >> >> I downloaded the source of camel 2.0 and I looked at the
>>> >> >> >> FailOverLoadBalancer class. I think that this could answer to my
>>> >> >> question.
>>> >> >> >> I've tried to adapt the code to my requirement but I have some
>>> >> questions
>>> >> >> >> about the list of processors used in this class :
>>> >> >> >>
>>> >> >> >> 1. I don't know How to create or initialize the processors used
>>> for
>>> >> >> >> balancing user requests ?
>>> >> >> >>
>>> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
>>> >> >> >>
>>> >> >> >> 3. Whait is the syntaxe (maybe something like new
>>> >> Processor(myHttpURL))
>>> >> >> > Hi
>>> >> >> >
>>> >> >> > Yeah there is no nice DSL support for it and the loadbalance() DSL
>>> >> >> > does not have a nice support for custom load balancer.
>>> >> >> > So that is something we might need to improve in the future. I have
>>> to
>>> >> >> > remember this thread.
>>> >> >> >
>>> >> >> > So what you basically have to do is to add your custom load
>>> balancer
>>> >> >> > as a processor, so use the process() DSL.
>>> >> >> >
>>> >> >> > And your custom fail over loadbalancer can accept a list of
>>> endpoints
>>> >> >> > to select among. You can wrap an endpoint to a processor
>>> >> >> > with the SendToProcessor.
>>> >> >> >
>>> >> >> > Something like this
>>> >> >> >
>>> >> >> > MyFailover my = new MyFailoverProcessor()l;
>>> >> >> > my.addEndpoint("foo");
>>> >> >> > my.addEndpoint("bar");
>>> >> >> >
>>> >> >> >
>>> >> >> > And in the route DSL you just route to your processor
>>> >> >> > from(x).process(my);
>>> >> >> >
>>> >> >> > And in the addEndpoint method you add the endpoint by wrapping it
>>> with
>>> >> >> > a SendToProcessor so you can add it to the LoadBalancerSupport
>>> class.
>>> >> >> >
>>> >> >> > See how it goes and ask again tomorrow when I am back in the office
>>> >> >> > and can better work. As I sit now with the laptop in the living
>>> room.
>>> >> >> >
>>> >> >> >
>>> >> >> >>
>>> >> >> >> Thanks for help
>>> >> >> >>
>>> >> >> >>
>>> >> >> >>
>>> >> >> >>
>>> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
>>> claus.ibsen@gmail.com
>>> >> >
>>> >> >> wrote:
>>> >> >> >>
>>> >> >> >>> Hi
>>> >> >> >>>
>>> >> >> >>> There are load balancers with Camel
>>> >> >> >>> http://camel.apache.org/load-balancer.html
>>> >> >> >>>
>>> >> >> >>> And there is a failover load balancer as well that can do a
>>> simple
>>> >> try
>>> >> >> >>> the next endpoint until success kinda style.
>>> >> >> >>> Its a bit primitive at the moment and we would like to improve
>>> that
>>> >> in
>>> >> >> >>> the future.
>>> >> >> >>>
>>> >> >> >>> But it allows you to implement your own load balancer and do your
>>> >> >> >>> strategy how you like it.
>>> >> >> >>>
>>> >> >> >>> Any feedback for features that could be needed for a more
>>> advanced
>>> >> >> >>> failover loadbalancer is much welcome.
>>> >> >> >>>
>>> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But you
>>> can
>>> >> >> >>> check the source code for 2.0 and create your own kinda to use in
>>> >> 1.x.
>>> >> >> >>>
>>> >> >> >>>
>>> >> >>
>>> >>
>>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>>> >> >> >>>
>>> >> >> >>>
>>> >> >> >>>
>>> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
>>> >> nasmo2009@googlemail.com
>>> >> >> >
>>> >> >> >>> wrote:
>>> >> >> >>> > Hi,
>>> >> >> >>> >
>>> >> >> >>> > I would like to implement the following route with Camel 1.6 :
>>> >> >> >>> >
>>> >> >> >>> > from("direct:endpointA")
>>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>>> >> >> >>> > .to("http://xxxxxx")
>>> >> >> >>> > .to("direct:endPointB")
>>> >> >> >>> >
>>> >> >> >>> > from("direct:endpointB")
>>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>>> >> >> >>> > .to("http://xxxxxx")
>>> >> >> >>> > .to("direct:endPointC")
>>> >> >> >>> >
>>> >> >> >>> > from("direct:endPointC")
>>> >> >> >>> > .to("xquery:response.xml");
>>> >> >> >>> >
>>> >> >> >>> > This route works fine if both URLs : http://myAddressA and
>>> >> >> >>> > http://myAddressBare accessible and no error occurs during the
>>> >> >> >>> > invocation.
>>> >> >> >>> > Unfortunately, sometimes these services become unreachable and
>>> I
>>> >> >> would
>>> >> >> >>> like
>>> >> >> >>> > to try other URLs until getting valid answer:
>>> >> >> >>> >
>>> >> >> >>> > If an exception happens when calling the URL http:/:myAddressA,
>>> I
>>> >> >> would
>>> >> >> >>> like
>>> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until
>>> getting
>>> >> >> valid
>>> >> >> >>> > HTTP response.
>>> >> >> >>> > The same thing with myAddressB ==> myAddressB1, myAddressB2,
>>> ...
>>> >> >> >>> >
>>> >> >> >>> > With java this could be simply coded like following :
>>> >> >> >>> >
>>> >> >> >>> > try
>>> >> >> >>> > {
>>> >> >> >>> > call_http(myAddressA)
>>> >> >> >>> > }
>>> >> >> >>> > catch(Throwable th)
>>> >> >> >>> > {
>>> >> >> >>> > try
>>> >> >> >>> > {
>>> >> >> >>> > call_http(myAddressA1)
>>> >> >> >>> > }
>>> >> >> >>> > catch(Exception x)
>>> >> >> >>> > {
>>> >> >> >>> > //Call addressA2
>>> >> >> >>> > ....
>>> >> >> >>> > }
>>> >> >> >>> > }
>>> >> >> >>> >
>>> >> >> >>> > I've tried the onException() mechanism and the
>>> deadLetterChannel
>>> >> >> >>> processor
>>> >> >> >>> > but I never get working my route.
>>> >> >> >>> >
>>> >> >> >>>
>>> >> >> >>>
>>> >> >> >>>
>>> >> >> >>> --
>>> >> >> >>> Claus Ibsen
>>> >> >> >>> Apache Camel Committer
>>> >> >> >>>
>>> >> >> >>> Open Source Integration: http://fusesource.com
>>> >> >> >>> Blog: http://davsclaus.blogspot.com/
>>> >> >> >>> Twitter: http://twitter.com/davsclaus
>>> >> >> >>>
>>> >> >> >>
>>> >> >> >
>>> >> >> >
>>> >> >> >
>>> >> >> > --
>>> >> >> > Claus Ibsen
>>> >> >> > Apache Camel Committer
>>> >> >> >
>>> >> >> > Open Source Integration: http://fusesource.com
>>> >> >> > Blog: http://davsclaus.blogspot.com/
>>> >> >> > Twitter: http://twitter.com/davsclaus
>>> >> >> >
>>> >> >>
>>> >> >>
>>> >> >>
>>> >> >> --
>>> >> >> Claus Ibsen
>>> >> >> Apache Camel Committer
>>> >> >>
>>> >> >> Open Source Integration: http://fusesource.com
>>> >> >> Blog: http://davsclaus.blogspot.com/
>>> >> >> Twitter: http://twitter.com/davsclaus
>>> >> >>
>>> >> >
>>> >>
>>> >>
>>> >>
>>> >> --
>>> >> Claus Ibsen
>>> >> Apache Camel Committer
>>> >>
>>> >> Open Source Integration: http://fusesource.com
>>> >> Blog: http://davsclaus.blogspot.com/
>>> >> Twitter: http://twitter.com/davsclaus
>>> >>
>>> >
>>>
>>>
>>>
>>> --
>>> Claus Ibsen
>>> Apache Camel Committer
>>>
>>> Open Source Integration: http://fusesource.com
>>> Blog: http://davsclaus.blogspot.com/
>>> Twitter: http://twitter.com/davsclaus
>>>
>>
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
Hi
Sometimes its easier to read the code when there is quite a bit if you
paste it using http://pastebin.com/ or the likes.
On Fri, May 15, 2009 at 5:44 PM, Nasim Anza <na...@googlemail.com> wrote:
> Thanks Claus for answers.
>
> My processor is working fine and it finds the URL to invoke but the problem
> is on the last step : the next endpoint is not called with right XML input :
>
> Just to explain my actual problem :
> Let's assume that my route is :
>
> from("direct:endpointA")
> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> .process(myFailOverProcessor("direct:endpointB")); //forward HTTP response
> to the direct:endpointB
>
> from("direct:endpointB")
> .to("log:display the XML input"); //just display it to compare XMLs
>
> The displayed XML on the "log:..." endpoint doesn't correspond to the http
> response of "http://myAddressA"...
>
> Here is my Processor class :
>
>
> public class FailOverProcessor implements Processor{
>
> public FailOverProcessor(String endpoint) {
> this.endpoint=endpoint;
> }
>
> public void process(Exchange exchange) throws Exception {
> Exchange out = null;
> int index = 0;
> out = processExchange(exchange);
>
> while (exchange.getException() != null){
>
> //reset the exchange exceptiuon
> exchange.setException(null);
>
> if (index++ < 4 ) {
> System.out.println(index+" : processExchange .....");
>
> out = processExchange(exchange);
> }
> }
>
> if(endpoint != null)
> {
> ProducerTemplate<Exchange> template =
> exchange.getContext().createProducerTemplate();
> if(out != null)
> {
>
> Message responseOut = exchange.getOut();
> int responseCode =
> responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE, Integer.class);
> System.out.println("\n\n Response out \\n" + responseCode +
> responseOut.getBody(String.class));
>
> //I've tried all the these calls but no valid response
> // template.send(endpoint, exchange.getOut().getExchange());
> // template.sendBody(endpoint, exchange.getBody());
> template.send(endpoint, exchange);
> }
> }
> }
>
> private Exchange processExchange(Exchange exchange) {
>
> Exchange out = null;
>
> try {
>
> //Define the strategy to use for processing message
> String uri =
> exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
> System.out.println("Current URI ==> "+uri);
>
> //just for test
> if(uri.equalsIgnoreCase("http://myAddressA"))
> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> http://serverA/appli1");
> else if(uri.equalsIgnoreCase("http://myAddressB"))
> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> http://serverB/appli2");
> else
> exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
> http://serverC/error");
>
> ProducerTemplate<Exchange> template =
> exchange.getContext().createProducerTemplate();
>
> out = template.send(uri, exchange);
>
> } catch (Throwable th) {
> //Set the thrown exception
> exchange.setException(th.getCause());
> }
>
> return out;
> }
> }
>
> Thanks for your help
> Nasmo
>
>
>
>
> On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <cl...@gmail.com> wrote:
>
>> You need to test the exchange afterwards if there was an exception.
>>
>> template.send(endpoint, exchange);
>> if (exchange.getException() != null) {
>> // ops it failed so call the next URI as fallback
>> ...
>> }
>>
>>
>>
>>
>> >
>> > Unfortunately this doesn't change anything on the SMIX console. I have
>> the
>> > same error :
>> >
>> > FATAL - DeadLetterChannel - Failed delivery for exchangeId:
>> > ID-ROME/1982-1242375956166/0-
>> > Handled by the failure
>> processor:sendTo(Endpoint[direct:deadLetterChannel])
>> >
>> > Thanks for help
>> >
>> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <cl...@gmail.com>
>> wrote:
>> >
>> >> Hi
>> >>
>> >> You should *not* route after your custom failover processor. You
>> >> custom failover processor should be the end of the route (eg no more
>> >> .to after your processor).
>> >>
>> >>
>> >>
>> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <na...@googlemail.com>
>> >> wrote:
>> >> > Hi,
>> >> >
>> >> > I’ve tried this solution:
>> >> > I started by developing a processor that loops on URIs until getting a
>> >> valid
>> >> > answer.
>> >> > The only problem is my route is interrupted at the end of the first
>> >> > processing, so no way to pass from first block (addressA) to next
>> block
>> >> > (AddressB).
>> >> >
>> >> > The process() method loops on all URI until getting the valid URI.
>> This
>> >> > works but after that I got a fatal error and the route flow was
>> >> interrupted.
>> >> > Below the error I got on ServiceMix console:
>> >> >
>> >> > ----------------
>> >> >
>> >> > FATAL - DeadLetterChannel - Failed delivery for
>> exchangeId:
>> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
>> >> > sendTo(Endpoint[direct:deadLetterChannel])
>> >> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
>> >> doIntercept
>> >> > INFO: Interceptor has thrown exception, unwinding now
>> >> > org.apache.xerces.dom.TextImpl
>> >> >
>> >> > ----------------
>> >> >
>> >> > Here is my Camel route:
>> >> >
>> >> > * //Declare Deadletter processor*
>> >> >
>> >> >
>> >>
>> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
>> >> > *
>> >> >
>> >> > * //Declare global exception*
>> >> >
>> >> > *onException(Exception.class).maximumRedeliveries(5) //5 : because I
>> have
>> >> 5
>> >> > address maximum to call*
>> >> >
>> >> > *final Processor myprocessor() = new Processor(Exchange exchange)
>> throws
>> >> > Exception{*
>> >> > **
>> >> >
>> >> > *ProducerTemplate<Exchange> template
>> >> > exchange.getContext().createProducerTemplate();
>> >> > String uri =
>> >> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
>> >> > *
>> >> >
>> >> > *//This method returns the valid list depending on the current http
>> URI*
>> >> >
>> >> > *List<Strig> uris = getUriList(uri);*
>> >> >
>> >> > *for (String uri : uris) {*
>> >> >
>> >> > * try {*
>> >> >
>> >> > * template.send(uri, exchange);*
>> >> >
>> >> > * } catch (Exception e) {*
>> >> >
>> >> > * exchange.setExceptipn(e);*
>> >> >
>> >> > * }*
>> >> >
>> >> > * if (exchange.getException() == null) {*
>> >> >
>> >> > * return;
>> >> > }
>> >> > }
>> >> > }*
>> >> >
>> >> > * *
>> >> >
>> >> > *from("direct:endpointA")
>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >> > .process(myUrlLookerProcessor())
>> >> > .to("direct:endPointB")*
>> >> >
>> >> > *from("direct:endpointB")
>> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>> >> > .process(myUrlLookerProcessor())
>> >> > .to("direct:endPointC")*
>> >> >
>> >> > *
>> >> > from("direct:endPointC")
>> >> > .to("xquery:response.xml");*
>> >> >
>> >> > *from("direct:letter")
>> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
>> >> >
>> >> >
>> >> >
>> >> > Thanks in advance for help.
>> >> >
>> >> > Nasmo
>> >> >
>> >> >
>> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <cl...@gmail.com>
>> >> wrote:
>> >> >
>> >> >> Hi
>> >> >>
>> >> >> BTW You can also always just use a Processor and implement the
>> >> >> failover logic yourself as pure Java with try .. catch and use the
>> >> >> ProducerTemplate to send the exchange to the endpoint based on the
>> >> >> URI.
>> >> >>
>> >> >> Something like
>> >> >> ProducerTemplate template = // get it from CamelContext and get it
>> once
>> >> >> List<Strig> uris = ...
>> >> >>
>> >> >> for (String uri : uris) {
>> >> >> try {
>> >> >> template.send(uri, exchange);
>> >> >> } catch (Exception e) {
>> >> >> exchange.setExceptipn(e);
>> >> >> }
>> >> >> if (exchange.getException() == null) {
>> >> >> return;
>> >> >> }
>> >> >> }
>> >> >>
>> >> >>
>> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <cl...@gmail.com>
>> >> >> wrote:
>> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
>> nasmo2009@googlemail.com
>> >> >
>> >> >> wrote:
>> >> >> >> Thanks Claus for your quick answer.
>> >> >> >>
>> >> >> >> I downloaded the source of camel 2.0 and I looked at the
>> >> >> >> FailOverLoadBalancer class. I think that this could answer to my
>> >> >> question.
>> >> >> >> I've tried to adapt the code to my requirement but I have some
>> >> questions
>> >> >> >> about the list of processors used in this class :
>> >> >> >>
>> >> >> >> 1. I don't know How to create or initialize the processors used
>> for
>> >> >> >> balancing user requests ?
>> >> >> >>
>> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
>> >> >> >>
>> >> >> >> 3. Whait is the syntaxe (maybe something like new
>> >> Processor(myHttpURL))
>> >> >> > Hi
>> >> >> >
>> >> >> > Yeah there is no nice DSL support for it and the loadbalance() DSL
>> >> >> > does not have a nice support for custom load balancer.
>> >> >> > So that is something we might need to improve in the future. I have
>> to
>> >> >> > remember this thread.
>> >> >> >
>> >> >> > So what you basically have to do is to add your custom load
>> balancer
>> >> >> > as a processor, so use the process() DSL.
>> >> >> >
>> >> >> > And your custom fail over loadbalancer can accept a list of
>> endpoints
>> >> >> > to select among. You can wrap an endpoint to a processor
>> >> >> > with the SendToProcessor.
>> >> >> >
>> >> >> > Something like this
>> >> >> >
>> >> >> > MyFailover my = new MyFailoverProcessor()l;
>> >> >> > my.addEndpoint("foo");
>> >> >> > my.addEndpoint("bar");
>> >> >> >
>> >> >> >
>> >> >> > And in the route DSL you just route to your processor
>> >> >> > from(x).process(my);
>> >> >> >
>> >> >> > And in the addEndpoint method you add the endpoint by wrapping it
>> with
>> >> >> > a SendToProcessor so you can add it to the LoadBalancerSupport
>> class.
>> >> >> >
>> >> >> > See how it goes and ask again tomorrow when I am back in the office
>> >> >> > and can better work. As I sit now with the laptop in the living
>> room.
>> >> >> >
>> >> >> >
>> >> >> >>
>> >> >> >> Thanks for help
>> >> >> >>
>> >> >> >>
>> >> >> >>
>> >> >> >>
>> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
>> claus.ibsen@gmail.com
>> >> >
>> >> >> wrote:
>> >> >> >>
>> >> >> >>> Hi
>> >> >> >>>
>> >> >> >>> There are load balancers with Camel
>> >> >> >>> http://camel.apache.org/load-balancer.html
>> >> >> >>>
>> >> >> >>> And there is a failover load balancer as well that can do a
>> simple
>> >> try
>> >> >> >>> the next endpoint until success kinda style.
>> >> >> >>> Its a bit primitive at the moment and we would like to improve
>> that
>> >> in
>> >> >> >>> the future.
>> >> >> >>>
>> >> >> >>> But it allows you to implement your own load balancer and do your
>> >> >> >>> strategy how you like it.
>> >> >> >>>
>> >> >> >>> Any feedback for features that could be needed for a more
>> advanced
>> >> >> >>> failover loadbalancer is much welcome.
>> >> >> >>>
>> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But you
>> can
>> >> >> >>> check the source code for 2.0 and create your own kinda to use in
>> >> 1.x.
>> >> >> >>>
>> >> >> >>>
>> >> >>
>> >>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>> >> >> >>>
>> >> >> >>>
>> >> >> >>>
>> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
>> >> nasmo2009@googlemail.com
>> >> >> >
>> >> >> >>> wrote:
>> >> >> >>> > Hi,
>> >> >> >>> >
>> >> >> >>> > I would like to implement the following route with Camel 1.6 :
>> >> >> >>> >
>> >> >> >>> > from("direct:endpointA")
>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >> >> >>> > .to("http://xxxxxx")
>> >> >> >>> > .to("direct:endPointB")
>> >> >> >>> >
>> >> >> >>> > from("direct:endpointB")
>> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>> >> >> >>> > .to("http://xxxxxx")
>> >> >> >>> > .to("direct:endPointC")
>> >> >> >>> >
>> >> >> >>> > from("direct:endPointC")
>> >> >> >>> > .to("xquery:response.xml");
>> >> >> >>> >
>> >> >> >>> > This route works fine if both URLs : http://myAddressA and
>> >> >> >>> > http://myAddressBare accessible and no error occurs during the
>> >> >> >>> > invocation.
>> >> >> >>> > Unfortunately, sometimes these services become unreachable and
>> I
>> >> >> would
>> >> >> >>> like
>> >> >> >>> > to try other URLs until getting valid answer:
>> >> >> >>> >
>> >> >> >>> > If an exception happens when calling the URL http:/:myAddressA,
>> I
>> >> >> would
>> >> >> >>> like
>> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until
>> getting
>> >> >> valid
>> >> >> >>> > HTTP response.
>> >> >> >>> > The same thing with myAddressB ==> myAddressB1, myAddressB2,
>> ...
>> >> >> >>> >
>> >> >> >>> > With java this could be simply coded like following :
>> >> >> >>> >
>> >> >> >>> > try
>> >> >> >>> > {
>> >> >> >>> > call_http(myAddressA)
>> >> >> >>> > }
>> >> >> >>> > catch(Throwable th)
>> >> >> >>> > {
>> >> >> >>> > try
>> >> >> >>> > {
>> >> >> >>> > call_http(myAddressA1)
>> >> >> >>> > }
>> >> >> >>> > catch(Exception x)
>> >> >> >>> > {
>> >> >> >>> > //Call addressA2
>> >> >> >>> > ....
>> >> >> >>> > }
>> >> >> >>> > }
>> >> >> >>> >
>> >> >> >>> > I've tried the onException() mechanism and the
>> deadLetterChannel
>> >> >> >>> processor
>> >> >> >>> > but I never get working my route.
>> >> >> >>> >
>> >> >> >>>
>> >> >> >>>
>> >> >> >>>
>> >> >> >>> --
>> >> >> >>> Claus Ibsen
>> >> >> >>> Apache Camel Committer
>> >> >> >>>
>> >> >> >>> Open Source Integration: http://fusesource.com
>> >> >> >>> Blog: http://davsclaus.blogspot.com/
>> >> >> >>> Twitter: http://twitter.com/davsclaus
>> >> >> >>>
>> >> >> >>
>> >> >> >
>> >> >> >
>> >> >> >
>> >> >> > --
>> >> >> > Claus Ibsen
>> >> >> > Apache Camel Committer
>> >> >> >
>> >> >> > Open Source Integration: http://fusesource.com
>> >> >> > Blog: http://davsclaus.blogspot.com/
>> >> >> > Twitter: http://twitter.com/davsclaus
>> >> >> >
>> >> >>
>> >> >>
>> >> >>
>> >> >> --
>> >> >> Claus Ibsen
>> >> >> Apache Camel Committer
>> >> >>
>> >> >> Open Source Integration: http://fusesource.com
>> >> >> Blog: http://davsclaus.blogspot.com/
>> >> >> Twitter: http://twitter.com/davsclaus
>> >> >>
>> >> >
>> >>
>> >>
>> >>
>> >> --
>> >> Claus Ibsen
>> >> Apache Camel Committer
>> >>
>> >> Open Source Integration: http://fusesource.com
>> >> Blog: http://davsclaus.blogspot.com/
>> >> Twitter: http://twitter.com/davsclaus
>> >>
>> >
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Nasim Anza <na...@googlemail.com>.
Thanks Claus for answers.
My processor is working fine and it finds the URL to invoke but the problem
is on the last step : the next endpoint is not called with right XML input :
Just to explain my actual problem :
Let's assume that my route is :
from("direct:endpointA")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
.process(myFailOverProcessor("direct:endpointB")); //forward HTTP response
to the direct:endpointB
from("direct:endpointB")
.to("log:display the XML input"); //just display it to compare XMLs
The displayed XML on the "log:..." endpoint doesn't correspond to the http
response of "http://myAddressA"...
Here is my Processor class :
public class FailOverProcessor implements Processor{
public FailOverProcessor(String endpoint) {
this.endpoint=endpoint;
}
public void process(Exchange exchange) throws Exception {
Exchange out = null;
int index = 0;
out = processExchange(exchange);
while (exchange.getException() != null){
//reset the exchange exceptiuon
exchange.setException(null);
if (index++ < 4 ) {
System.out.println(index+" : processExchange .....");
out = processExchange(exchange);
}
}
if(endpoint != null)
{
ProducerTemplate<Exchange> template =
exchange.getContext().createProducerTemplate();
if(out != null)
{
Message responseOut = exchange.getOut();
int responseCode =
responseOut.getHeader(HttpProducer.HTTP_RESPONSE_CODE, Integer.class);
System.out.println("\n\n Response out \\n" + responseCode +
responseOut.getBody(String.class));
//I've tried all the these calls but no valid response
// template.send(endpoint, exchange.getOut().getExchange());
// template.sendBody(endpoint, exchange.getBody());
template.send(endpoint, exchange);
}
}
}
private Exchange processExchange(Exchange exchange) {
Exchange out = null;
try {
//Define the strategy to use for processing message
String uri =
exchange.getIn().getHeader(org.apache.camel.component.http.HttpProducer.HTTP_URI).toString();
System.out.println("Current URI ==> "+uri);
//just for test
if(uri.equalsIgnoreCase("http://myAddressA"))
exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
http://serverA/appli1");
else if(uri.equalsIgnoreCase("http://myAddressB"))
exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
http://serverB/appli2");
else
exchange.getIn().setHeader(HttpProducer.HTTP_URI, "
http://serverC/error");
ProducerTemplate<Exchange> template =
exchange.getContext().createProducerTemplate();
out = template.send(uri, exchange);
} catch (Throwable th) {
//Set the thrown exception
exchange.setException(th.getCause());
}
return out;
}
}
Thanks for your help
Nasmo
On Fri, May 15, 2009 at 1:00 PM, Claus Ibsen <cl...@gmail.com> wrote:
> You need to test the exchange afterwards if there was an exception.
>
> template.send(endpoint, exchange);
> if (exchange.getException() != null) {
> // ops it failed so call the next URI as fallback
> ...
> }
>
>
>
>
> >
> > Unfortunately this doesn't change anything on the SMIX console. I have
> the
> > same error :
> >
> > FATAL - DeadLetterChannel - Failed delivery for exchangeId:
> > ID-ROME/1982-1242375956166/0-
> > Handled by the failure
> processor:sendTo(Endpoint[direct:deadLetterChannel])
> >
> > Thanks for help
> >
> > On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <cl...@gmail.com>
> wrote:
> >
> >> Hi
> >>
> >> You should *not* route after your custom failover processor. You
> >> custom failover processor should be the end of the route (eg no more
> >> .to after your processor).
> >>
> >>
> >>
> >> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <na...@googlemail.com>
> >> wrote:
> >> > Hi,
> >> >
> >> > I’ve tried this solution:
> >> > I started by developing a processor that loops on URIs until getting a
> >> valid
> >> > answer.
> >> > The only problem is my route is interrupted at the end of the first
> >> > processing, so no way to pass from first block (addressA) to next
> block
> >> > (AddressB).
> >> >
> >> > The process() method loops on all URI until getting the valid URI.
> This
> >> > works but after that I got a fatal error and the route flow was
> >> interrupted.
> >> > Below the error I got on ServiceMix console:
> >> >
> >> > ----------------
> >> >
> >> > FATAL - DeadLetterChannel - Failed delivery for
> exchangeId:
> >> > ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
> >> > sendTo(Endpoint[direct:deadLetterChannel])
> >> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
> >> doIntercept
> >> > INFO: Interceptor has thrown exception, unwinding now
> >> > org.apache.xerces.dom.TextImpl
> >> >
> >> > ----------------
> >> >
> >> > Here is my Camel route:
> >> >
> >> > * //Declare Deadletter processor*
> >> >
> >> >
> >>
> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
> >> > *
> >> >
> >> > * //Declare global exception*
> >> >
> >> > *onException(Exception.class).maximumRedeliveries(5) //5 : because I
> have
> >> 5
> >> > address maximum to call*
> >> >
> >> > *final Processor myprocessor() = new Processor(Exchange exchange)
> throws
> >> > Exception{*
> >> > **
> >> >
> >> > *ProducerTemplate<Exchange> template
> >> > exchange.getContext().createProducerTemplate();
> >> > String uri =
> >> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
> >> > *
> >> >
> >> > *//This method returns the valid list depending on the current http
> URI*
> >> >
> >> > *List<Strig> uris = getUriList(uri);*
> >> >
> >> > *for (String uri : uris) {*
> >> >
> >> > * try {*
> >> >
> >> > * template.send(uri, exchange);*
> >> >
> >> > * } catch (Exception e) {*
> >> >
> >> > * exchange.setExceptipn(e);*
> >> >
> >> > * }*
> >> >
> >> > * if (exchange.getException() == null) {*
> >> >
> >> > * return;
> >> > }
> >> > }
> >> > }*
> >> >
> >> > * *
> >> >
> >> > *from("direct:endpointA")
> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >> > .process(myUrlLookerProcessor())
> >> > .to("direct:endPointB")*
> >> >
> >> > *from("direct:endpointB")
> >> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> >> > .process(myUrlLookerProcessor())
> >> > .to("direct:endPointC")*
> >> >
> >> > *
> >> > from("direct:endPointC")
> >> > .to("xquery:response.xml");*
> >> >
> >> > *from("direct:letter")
> >> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
> >> >
> >> >
> >> >
> >> > Thanks in advance for help.
> >> >
> >> > Nasmo
> >> >
> >> >
> >> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <cl...@gmail.com>
> >> wrote:
> >> >
> >> >> Hi
> >> >>
> >> >> BTW You can also always just use a Processor and implement the
> >> >> failover logic yourself as pure Java with try .. catch and use the
> >> >> ProducerTemplate to send the exchange to the endpoint based on the
> >> >> URI.
> >> >>
> >> >> Something like
> >> >> ProducerTemplate template = // get it from CamelContext and get it
> once
> >> >> List<Strig> uris = ...
> >> >>
> >> >> for (String uri : uris) {
> >> >> try {
> >> >> template.send(uri, exchange);
> >> >> } catch (Exception e) {
> >> >> exchange.setExceptipn(e);
> >> >> }
> >> >> if (exchange.getException() == null) {
> >> >> return;
> >> >> }
> >> >> }
> >> >>
> >> >>
> >> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <cl...@gmail.com>
> >> >> wrote:
> >> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <
> nasmo2009@googlemail.com
> >> >
> >> >> wrote:
> >> >> >> Thanks Claus for your quick answer.
> >> >> >>
> >> >> >> I downloaded the source of camel 2.0 and I looked at the
> >> >> >> FailOverLoadBalancer class. I think that this could answer to my
> >> >> question.
> >> >> >> I've tried to adapt the code to my requirement but I have some
> >> questions
> >> >> >> about the list of processors used in this class :
> >> >> >>
> >> >> >> 1. I don't know How to create or initialize the processors used
> for
> >> >> >> balancing user requests ?
> >> >> >>
> >> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
> >> >> >>
> >> >> >> 3. Whait is the syntaxe (maybe something like new
> >> Processor(myHttpURL))
> >> >> > Hi
> >> >> >
> >> >> > Yeah there is no nice DSL support for it and the loadbalance() DSL
> >> >> > does not have a nice support for custom load balancer.
> >> >> > So that is something we might need to improve in the future. I have
> to
> >> >> > remember this thread.
> >> >> >
> >> >> > So what you basically have to do is to add your custom load
> balancer
> >> >> > as a processor, so use the process() DSL.
> >> >> >
> >> >> > And your custom fail over loadbalancer can accept a list of
> endpoints
> >> >> > to select among. You can wrap an endpoint to a processor
> >> >> > with the SendToProcessor.
> >> >> >
> >> >> > Something like this
> >> >> >
> >> >> > MyFailover my = new MyFailoverProcessor()l;
> >> >> > my.addEndpoint("foo");
> >> >> > my.addEndpoint("bar");
> >> >> >
> >> >> >
> >> >> > And in the route DSL you just route to your processor
> >> >> > from(x).process(my);
> >> >> >
> >> >> > And in the addEndpoint method you add the endpoint by wrapping it
> with
> >> >> > a SendToProcessor so you can add it to the LoadBalancerSupport
> class.
> >> >> >
> >> >> > See how it goes and ask again tomorrow when I am back in the office
> >> >> > and can better work. As I sit now with the laptop in the living
> room.
> >> >> >
> >> >> >
> >> >> >>
> >> >> >> Thanks for help
> >> >> >>
> >> >> >>
> >> >> >>
> >> >> >>
> >> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <
> claus.ibsen@gmail.com
> >> >
> >> >> wrote:
> >> >> >>
> >> >> >>> Hi
> >> >> >>>
> >> >> >>> There are load balancers with Camel
> >> >> >>> http://camel.apache.org/load-balancer.html
> >> >> >>>
> >> >> >>> And there is a failover load balancer as well that can do a
> simple
> >> try
> >> >> >>> the next endpoint until success kinda style.
> >> >> >>> Its a bit primitive at the moment and we would like to improve
> that
> >> in
> >> >> >>> the future.
> >> >> >>>
> >> >> >>> But it allows you to implement your own load balancer and do your
> >> >> >>> strategy how you like it.
> >> >> >>>
> >> >> >>> Any feedback for features that could be needed for a more
> advanced
> >> >> >>> failover loadbalancer is much welcome.
> >> >> >>>
> >> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But you
> can
> >> >> >>> check the source code for 2.0 and create your own kinda to use in
> >> 1.x.
> >> >> >>>
> >> >> >>>
> >> >>
> >>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
> >> >> >>>
> >> >> >>>
> >> >> >>>
> >> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
> >> nasmo2009@googlemail.com
> >> >> >
> >> >> >>> wrote:
> >> >> >>> > Hi,
> >> >> >>> >
> >> >> >>> > I would like to implement the following route with Camel 1.6 :
> >> >> >>> >
> >> >> >>> > from("direct:endpointA")
> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >> >> >>> > .to("http://xxxxxx")
> >> >> >>> > .to("direct:endPointB")
> >> >> >>> >
> >> >> >>> > from("direct:endpointB")
> >> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> >> >> >>> > .to("http://xxxxxx")
> >> >> >>> > .to("direct:endPointC")
> >> >> >>> >
> >> >> >>> > from("direct:endPointC")
> >> >> >>> > .to("xquery:response.xml");
> >> >> >>> >
> >> >> >>> > This route works fine if both URLs : http://myAddressA and
> >> >> >>> > http://myAddressBare accessible and no error occurs during the
> >> >> >>> > invocation.
> >> >> >>> > Unfortunately, sometimes these services become unreachable and
> I
> >> >> would
> >> >> >>> like
> >> >> >>> > to try other URLs until getting valid answer:
> >> >> >>> >
> >> >> >>> > If an exception happens when calling the URL http:/:myAddressA,
> I
> >> >> would
> >> >> >>> like
> >> >> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until
> getting
> >> >> valid
> >> >> >>> > HTTP response.
> >> >> >>> > The same thing with myAddressB ==> myAddressB1, myAddressB2,
> ...
> >> >> >>> >
> >> >> >>> > With java this could be simply coded like following :
> >> >> >>> >
> >> >> >>> > try
> >> >> >>> > {
> >> >> >>> > call_http(myAddressA)
> >> >> >>> > }
> >> >> >>> > catch(Throwable th)
> >> >> >>> > {
> >> >> >>> > try
> >> >> >>> > {
> >> >> >>> > call_http(myAddressA1)
> >> >> >>> > }
> >> >> >>> > catch(Exception x)
> >> >> >>> > {
> >> >> >>> > //Call addressA2
> >> >> >>> > ....
> >> >> >>> > }
> >> >> >>> > }
> >> >> >>> >
> >> >> >>> > I've tried the onException() mechanism and the
> deadLetterChannel
> >> >> >>> processor
> >> >> >>> > but I never get working my route.
> >> >> >>> >
> >> >> >>>
> >> >> >>>
> >> >> >>>
> >> >> >>> --
> >> >> >>> Claus Ibsen
> >> >> >>> Apache Camel Committer
> >> >> >>>
> >> >> >>> Open Source Integration: http://fusesource.com
> >> >> >>> Blog: http://davsclaus.blogspot.com/
> >> >> >>> Twitter: http://twitter.com/davsclaus
> >> >> >>>
> >> >> >>
> >> >> >
> >> >> >
> >> >> >
> >> >> > --
> >> >> > Claus Ibsen
> >> >> > Apache Camel Committer
> >> >> >
> >> >> > Open Source Integration: http://fusesource.com
> >> >> > Blog: http://davsclaus.blogspot.com/
> >> >> > Twitter: http://twitter.com/davsclaus
> >> >> >
> >> >>
> >> >>
> >> >>
> >> >> --
> >> >> Claus Ibsen
> >> >> Apache Camel Committer
> >> >>
> >> >> Open Source Integration: http://fusesource.com
> >> >> Blog: http://davsclaus.blogspot.com/
> >> >> Twitter: http://twitter.com/davsclaus
> >> >>
> >> >
> >>
> >>
> >>
> >> --
> >> Claus Ibsen
> >> Apache Camel Committer
> >>
> >> Open Source Integration: http://fusesource.com
> >> Blog: http://davsclaus.blogspot.com/
> >> Twitter: http://twitter.com/davsclaus
> >>
> >
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
On Fri, May 15, 2009 at 11:58 AM, Nasim Anza <na...@googlemail.com> wrote:
> I I understood, the route should be similar to the folllowing :
>
> from("direct:endpointA")
> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA<http://myaddressa/>
> ")
> .process(myFailOverProcessor("direct:endPointB"));
>
> from("direct:endpointB")
> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB<http://myaddressa/>
> ")
> .process(myFailOverProcessor("direct:endPointC"));
>
> from("direct:endPointC")
> .to("xquery:response.xml");*
>
> I added a constructor with the name of the next endpoint to which the result
> will be sent at the end of the failOverProcessor.process and the code to
> send exchange to the next endpoint:
>
> //After finding valid URL, we send the exchange to the next endpoint
> if(endpoint != null)
> {
> ProducerTemplate<Exchange> template =
> exchange.getContext().createProducerTemplate();
> template.send(endpoint, exchange);
> }
You need to test the exchange afterwards if there was an exception.
template.send(endpoint, exchange);
if (exchange.getException() != null) {
// ops it failed so call the next URI as fallback
...
}
and in case you want to reset the exception, you just call
exchange.setException(null);
and in your constructor you can have multiple endpoints, eg using a
List or varargs then you can loop the list of URI and try the next
one.
>
> Unfortunately this doesn't change anything on the SMIX console. I have the
> same error :
>
> FATAL - DeadLetterChannel - Failed delivery for exchangeId:
> ID-ROME/1982-1242375956166/0-
> Handled by the failure processor:sendTo(Endpoint[direct:deadLetterChannel])
>
> Thanks for help
>
> On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <cl...@gmail.com> wrote:
>
>> Hi
>>
>> You should *not* route after your custom failover processor. You
>> custom failover processor should be the end of the route (eg no more
>> .to after your processor).
>>
>>
>>
>> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <na...@googlemail.com>
>> wrote:
>> > Hi,
>> >
>> > I’ve tried this solution:
>> > I started by developing a processor that loops on URIs until getting a
>> valid
>> > answer.
>> > The only problem is my route is interrupted at the end of the first
>> > processing, so no way to pass from first block (addressA) to next block
>> > (AddressB).
>> >
>> > The process() method loops on all URI until getting the valid URI. This
>> > works but after that I got a fatal error and the route flow was
>> interrupted.
>> > Below the error I got on ServiceMix console:
>> >
>> > ----------------
>> >
>> > FATAL - DeadLetterChannel - Failed delivery for exchangeId:
>> > ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
>> > sendTo(Endpoint[direct:deadLetterChannel])
>> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
>> doIntercept
>> > INFO: Interceptor has thrown exception, unwinding now
>> > org.apache.xerces.dom.TextImpl
>> >
>> > ----------------
>> >
>> > Here is my Camel route:
>> >
>> > * //Declare Deadletter processor*
>> >
>> >
>> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
>> > *
>> >
>> > * //Declare global exception*
>> >
>> > *onException(Exception.class).maximumRedeliveries(5) //5 : because I have
>> 5
>> > address maximum to call*
>> >
>> > *final Processor myprocessor() = new Processor(Exchange exchange) throws
>> > Exception{*
>> > **
>> >
>> > *ProducerTemplate<Exchange> template
>> > exchange.getContext().createProducerTemplate();
>> > String uri =
>> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
>> > *
>> >
>> > *//This method returns the valid list depending on the current http URI*
>> >
>> > *List<Strig> uris = getUriList(uri);*
>> >
>> > *for (String uri : uris) {*
>> >
>> > * try {*
>> >
>> > * template.send(uri, exchange);*
>> >
>> > * } catch (Exception e) {*
>> >
>> > * exchange.setExceptipn(e);*
>> >
>> > * }*
>> >
>> > * if (exchange.getException() == null) {*
>> >
>> > * return;
>> > }
>> > }
>> > }*
>> >
>> > * *
>> >
>> > *from("direct:endpointA")
>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> > .process(myUrlLookerProcessor())
>> > .to("direct:endPointB")*
>> >
>> > *from("direct:endpointB")
>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>> > .process(myUrlLookerProcessor())
>> > .to("direct:endPointC")*
>> >
>> > *
>> > from("direct:endPointC")
>> > .to("xquery:response.xml");*
>> >
>> > *from("direct:letter")
>> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
>> >
>> >
>> >
>> > Thanks in advance for help.
>> >
>> > Nasmo
>> >
>> >
>> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <cl...@gmail.com>
>> wrote:
>> >
>> >> Hi
>> >>
>> >> BTW You can also always just use a Processor and implement the
>> >> failover logic yourself as pure Java with try .. catch and use the
>> >> ProducerTemplate to send the exchange to the endpoint based on the
>> >> URI.
>> >>
>> >> Something like
>> >> ProducerTemplate template = // get it from CamelContext and get it once
>> >> List<Strig> uris = ...
>> >>
>> >> for (String uri : uris) {
>> >> try {
>> >> template.send(uri, exchange);
>> >> } catch (Exception e) {
>> >> exchange.setExceptipn(e);
>> >> }
>> >> if (exchange.getException() == null) {
>> >> return;
>> >> }
>> >> }
>> >>
>> >>
>> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <cl...@gmail.com>
>> >> wrote:
>> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <nasmo2009@googlemail.com
>> >
>> >> wrote:
>> >> >> Thanks Claus for your quick answer.
>> >> >>
>> >> >> I downloaded the source of camel 2.0 and I looked at the
>> >> >> FailOverLoadBalancer class. I think that this could answer to my
>> >> question.
>> >> >> I've tried to adapt the code to my requirement but I have some
>> questions
>> >> >> about the list of processors used in this class :
>> >> >>
>> >> >> 1. I don't know How to create or initialize the processors used for
>> >> >> balancing user requests ?
>> >> >>
>> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
>> >> >>
>> >> >> 3. Whait is the syntaxe (maybe something like new
>> Processor(myHttpURL))
>> >> > Hi
>> >> >
>> >> > Yeah there is no nice DSL support for it and the loadbalance() DSL
>> >> > does not have a nice support for custom load balancer.
>> >> > So that is something we might need to improve in the future. I have to
>> >> > remember this thread.
>> >> >
>> >> > So what you basically have to do is to add your custom load balancer
>> >> > as a processor, so use the process() DSL.
>> >> >
>> >> > And your custom fail over loadbalancer can accept a list of endpoints
>> >> > to select among. You can wrap an endpoint to a processor
>> >> > with the SendToProcessor.
>> >> >
>> >> > Something like this
>> >> >
>> >> > MyFailover my = new MyFailoverProcessor()l;
>> >> > my.addEndpoint("foo");
>> >> > my.addEndpoint("bar");
>> >> >
>> >> >
>> >> > And in the route DSL you just route to your processor
>> >> > from(x).process(my);
>> >> >
>> >> > And in the addEndpoint method you add the endpoint by wrapping it with
>> >> > a SendToProcessor so you can add it to the LoadBalancerSupport class.
>> >> >
>> >> > See how it goes and ask again tomorrow when I am back in the office
>> >> > and can better work. As I sit now with the laptop in the living room.
>> >> >
>> >> >
>> >> >>
>> >> >> Thanks for help
>> >> >>
>> >> >>
>> >> >>
>> >> >>
>> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <claus.ibsen@gmail.com
>> >
>> >> wrote:
>> >> >>
>> >> >>> Hi
>> >> >>>
>> >> >>> There are load balancers with Camel
>> >> >>> http://camel.apache.org/load-balancer.html
>> >> >>>
>> >> >>> And there is a failover load balancer as well that can do a simple
>> try
>> >> >>> the next endpoint until success kinda style.
>> >> >>> Its a bit primitive at the moment and we would like to improve that
>> in
>> >> >>> the future.
>> >> >>>
>> >> >>> But it allows you to implement your own load balancer and do your
>> >> >>> strategy how you like it.
>> >> >>>
>> >> >>> Any feedback for features that could be needed for a more advanced
>> >> >>> failover loadbalancer is much welcome.
>> >> >>>
>> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But you can
>> >> >>> check the source code for 2.0 and create your own kinda to use in
>> 1.x.
>> >> >>>
>> >> >>>
>> >>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>> >> >>>
>> >> >>>
>> >> >>>
>> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
>> nasmo2009@googlemail.com
>> >> >
>> >> >>> wrote:
>> >> >>> > Hi,
>> >> >>> >
>> >> >>> > I would like to implement the following route with Camel 1.6 :
>> >> >>> >
>> >> >>> > from("direct:endpointA")
>> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >> >>> > .to("http://xxxxxx")
>> >> >>> > .to("direct:endPointB")
>> >> >>> >
>> >> >>> > from("direct:endpointB")
>> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>> >> >>> > .to("http://xxxxxx")
>> >> >>> > .to("direct:endPointC")
>> >> >>> >
>> >> >>> > from("direct:endPointC")
>> >> >>> > .to("xquery:response.xml");
>> >> >>> >
>> >> >>> > This route works fine if both URLs : http://myAddressA and
>> >> >>> > http://myAddressBare accessible and no error occurs during the
>> >> >>> > invocation.
>> >> >>> > Unfortunately, sometimes these services become unreachable and I
>> >> would
>> >> >>> like
>> >> >>> > to try other URLs until getting valid answer:
>> >> >>> >
>> >> >>> > If an exception happens when calling the URL http:/:myAddressA, I
>> >> would
>> >> >>> like
>> >> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until getting
>> >> valid
>> >> >>> > HTTP response.
>> >> >>> > The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
>> >> >>> >
>> >> >>> > With java this could be simply coded like following :
>> >> >>> >
>> >> >>> > try
>> >> >>> > {
>> >> >>> > call_http(myAddressA)
>> >> >>> > }
>> >> >>> > catch(Throwable th)
>> >> >>> > {
>> >> >>> > try
>> >> >>> > {
>> >> >>> > call_http(myAddressA1)
>> >> >>> > }
>> >> >>> > catch(Exception x)
>> >> >>> > {
>> >> >>> > //Call addressA2
>> >> >>> > ....
>> >> >>> > }
>> >> >>> > }
>> >> >>> >
>> >> >>> > I've tried the onException() mechanism and the deadLetterChannel
>> >> >>> processor
>> >> >>> > but I never get working my route.
>> >> >>> >
>> >> >>>
>> >> >>>
>> >> >>>
>> >> >>> --
>> >> >>> Claus Ibsen
>> >> >>> Apache Camel Committer
>> >> >>>
>> >> >>> Open Source Integration: http://fusesource.com
>> >> >>> Blog: http://davsclaus.blogspot.com/
>> >> >>> Twitter: http://twitter.com/davsclaus
>> >> >>>
>> >> >>
>> >> >
>> >> >
>> >> >
>> >> > --
>> >> > Claus Ibsen
>> >> > Apache Camel Committer
>> >> >
>> >> > Open Source Integration: http://fusesource.com
>> >> > Blog: http://davsclaus.blogspot.com/
>> >> > Twitter: http://twitter.com/davsclaus
>> >> >
>> >>
>> >>
>> >>
>> >> --
>> >> Claus Ibsen
>> >> Apache Camel Committer
>> >>
>> >> Open Source Integration: http://fusesource.com
>> >> Blog: http://davsclaus.blogspot.com/
>> >> Twitter: http://twitter.com/davsclaus
>> >>
>> >
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Nasim Anza <na...@googlemail.com>.
I I understood, the route should be similar to the folllowing :
from("direct:endpointA")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA<http://myaddressa/>
")
.process(myFailOverProcessor("direct:endPointB"));
from("direct:endpointB")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB<http://myaddressa/>
")
.process(myFailOverProcessor("direct:endPointC"));
from("direct:endPointC")
.to("xquery:response.xml");*
I added a constructor with the name of the next endpoint to which the result
will be sent at the end of the failOverProcessor.process and the code to
send exchange to the next endpoint:
//After finding valid URL, we send the exchange to the next endpoint
if(endpoint != null)
{
ProducerTemplate<Exchange> template =
exchange.getContext().createProducerTemplate();
template.send(endpoint, exchange);
}
Unfortunately this doesn't change anything on the SMIX console. I have the
same error :
FATAL - DeadLetterChannel - Failed delivery for exchangeId:
ID-ROME/1982-1242375956166/0-
Handled by the failure processor:sendTo(Endpoint[direct:deadLetterChannel])
Thanks for help
On Fri, May 15, 2009 at 11:10 AM, Claus Ibsen <cl...@gmail.com> wrote:
> Hi
>
> You should *not* route after your custom failover processor. You
> custom failover processor should be the end of the route (eg no more
> .to after your processor).
>
>
>
> On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <na...@googlemail.com>
> wrote:
> > Hi,
> >
> > I’ve tried this solution:
> > I started by developing a processor that loops on URIs until getting a
> valid
> > answer.
> > The only problem is my route is interrupted at the end of the first
> > processing, so no way to pass from first block (addressA) to next block
> > (AddressB).
> >
> > The process() method loops on all URI until getting the valid URI. This
> > works but after that I got a fatal error and the route flow was
> interrupted.
> > Below the error I got on ServiceMix console:
> >
> > ----------------
> >
> > FATAL - DeadLetterChannel - Failed delivery for exchangeId:
> > ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
> > sendTo(Endpoint[direct:deadLetterChannel])
> > 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain
> doIntercept
> > INFO: Interceptor has thrown exception, unwinding now
> > org.apache.xerces.dom.TextImpl
> >
> > ----------------
> >
> > Here is my Camel route:
> >
> > * //Declare Deadletter processor*
> >
> >
> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
> > *
> >
> > * //Declare global exception*
> >
> > *onException(Exception.class).maximumRedeliveries(5) //5 : because I have
> 5
> > address maximum to call*
> >
> > *final Processor myprocessor() = new Processor(Exchange exchange) throws
> > Exception{*
> > **
> >
> > *ProducerTemplate<Exchange> template
> > exchange.getContext().createProducerTemplate();
> > String uri =
> exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
> > *
> >
> > *//This method returns the valid list depending on the current http URI*
> >
> > *List<Strig> uris = getUriList(uri);*
> >
> > *for (String uri : uris) {*
> >
> > * try {*
> >
> > * template.send(uri, exchange);*
> >
> > * } catch (Exception e) {*
> >
> > * exchange.setExceptipn(e);*
> >
> > * }*
> >
> > * if (exchange.getException() == null) {*
> >
> > * return;
> > }
> > }
> > }*
> >
> > * *
> >
> > *from("direct:endpointA")
> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> > .process(myUrlLookerProcessor())
> > .to("direct:endPointB")*
> >
> > *from("direct:endpointB")
> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> > .process(myUrlLookerProcessor())
> > .to("direct:endPointC")*
> >
> > *
> > from("direct:endPointC")
> > .to("xquery:response.xml");*
> >
> > *from("direct:letter")
> > .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
> >
> >
> >
> > Thanks in advance for help.
> >
> > Nasmo
> >
> >
> > On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <cl...@gmail.com>
> wrote:
> >
> >> Hi
> >>
> >> BTW You can also always just use a Processor and implement the
> >> failover logic yourself as pure Java with try .. catch and use the
> >> ProducerTemplate to send the exchange to the endpoint based on the
> >> URI.
> >>
> >> Something like
> >> ProducerTemplate template = // get it from CamelContext and get it once
> >> List<Strig> uris = ...
> >>
> >> for (String uri : uris) {
> >> try {
> >> template.send(uri, exchange);
> >> } catch (Exception e) {
> >> exchange.setExceptipn(e);
> >> }
> >> if (exchange.getException() == null) {
> >> return;
> >> }
> >> }
> >>
> >>
> >> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <cl...@gmail.com>
> >> wrote:
> >> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <nasmo2009@googlemail.com
> >
> >> wrote:
> >> >> Thanks Claus for your quick answer.
> >> >>
> >> >> I downloaded the source of camel 2.0 and I looked at the
> >> >> FailOverLoadBalancer class. I think that this could answer to my
> >> question.
> >> >> I've tried to adapt the code to my requirement but I have some
> questions
> >> >> about the list of processors used in this class :
> >> >>
> >> >> 1. I don't know How to create or initialize the processors used for
> >> >> balancing user requests ?
> >> >>
> >> >> 2. Shall I create a camel Processor for each HTTP URL ?
> >> >>
> >> >> 3. Whait is the syntaxe (maybe something like new
> Processor(myHttpURL))
> >> > Hi
> >> >
> >> > Yeah there is no nice DSL support for it and the loadbalance() DSL
> >> > does not have a nice support for custom load balancer.
> >> > So that is something we might need to improve in the future. I have to
> >> > remember this thread.
> >> >
> >> > So what you basically have to do is to add your custom load balancer
> >> > as a processor, so use the process() DSL.
> >> >
> >> > And your custom fail over loadbalancer can accept a list of endpoints
> >> > to select among. You can wrap an endpoint to a processor
> >> > with the SendToProcessor.
> >> >
> >> > Something like this
> >> >
> >> > MyFailover my = new MyFailoverProcessor()l;
> >> > my.addEndpoint("foo");
> >> > my.addEndpoint("bar");
> >> >
> >> >
> >> > And in the route DSL you just route to your processor
> >> > from(x).process(my);
> >> >
> >> > And in the addEndpoint method you add the endpoint by wrapping it with
> >> > a SendToProcessor so you can add it to the LoadBalancerSupport class.
> >> >
> >> > See how it goes and ask again tomorrow when I am back in the office
> >> > and can better work. As I sit now with the laptop in the living room.
> >> >
> >> >
> >> >>
> >> >> Thanks for help
> >> >>
> >> >>
> >> >>
> >> >>
> >> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <claus.ibsen@gmail.com
> >
> >> wrote:
> >> >>
> >> >>> Hi
> >> >>>
> >> >>> There are load balancers with Camel
> >> >>> http://camel.apache.org/load-balancer.html
> >> >>>
> >> >>> And there is a failover load balancer as well that can do a simple
> try
> >> >>> the next endpoint until success kinda style.
> >> >>> Its a bit primitive at the moment and we would like to improve that
> in
> >> >>> the future.
> >> >>>
> >> >>> But it allows you to implement your own load balancer and do your
> >> >>> strategy how you like it.
> >> >>>
> >> >>> Any feedback for features that could be needed for a more advanced
> >> >>> failover loadbalancer is much welcome.
> >> >>>
> >> >>> Ah the failover loadbalancer is not part of Camel 1.x. But you can
> >> >>> check the source code for 2.0 and create your own kinda to use in
> 1.x.
> >> >>>
> >> >>>
> >>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
> >> >>>
> >> >>>
> >> >>>
> >> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <
> nasmo2009@googlemail.com
> >> >
> >> >>> wrote:
> >> >>> > Hi,
> >> >>> >
> >> >>> > I would like to implement the following route with Camel 1.6 :
> >> >>> >
> >> >>> > from("direct:endpointA")
> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >> >>> > .to("http://xxxxxx")
> >> >>> > .to("direct:endPointB")
> >> >>> >
> >> >>> > from("direct:endpointB")
> >> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> >> >>> > .to("http://xxxxxx")
> >> >>> > .to("direct:endPointC")
> >> >>> >
> >> >>> > from("direct:endPointC")
> >> >>> > .to("xquery:response.xml");
> >> >>> >
> >> >>> > This route works fine if both URLs : http://myAddressA and
> >> >>> > http://myAddressBare accessible and no error occurs during the
> >> >>> > invocation.
> >> >>> > Unfortunately, sometimes these services become unreachable and I
> >> would
> >> >>> like
> >> >>> > to try other URLs until getting valid answer:
> >> >>> >
> >> >>> > If an exception happens when calling the URL http:/:myAddressA, I
> >> would
> >> >>> like
> >> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until getting
> >> valid
> >> >>> > HTTP response.
> >> >>> > The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
> >> >>> >
> >> >>> > With java this could be simply coded like following :
> >> >>> >
> >> >>> > try
> >> >>> > {
> >> >>> > call_http(myAddressA)
> >> >>> > }
> >> >>> > catch(Throwable th)
> >> >>> > {
> >> >>> > try
> >> >>> > {
> >> >>> > call_http(myAddressA1)
> >> >>> > }
> >> >>> > catch(Exception x)
> >> >>> > {
> >> >>> > //Call addressA2
> >> >>> > ....
> >> >>> > }
> >> >>> > }
> >> >>> >
> >> >>> > I've tried the onException() mechanism and the deadLetterChannel
> >> >>> processor
> >> >>> > but I never get working my route.
> >> >>> >
> >> >>>
> >> >>>
> >> >>>
> >> >>> --
> >> >>> Claus Ibsen
> >> >>> Apache Camel Committer
> >> >>>
> >> >>> Open Source Integration: http://fusesource.com
> >> >>> Blog: http://davsclaus.blogspot.com/
> >> >>> Twitter: http://twitter.com/davsclaus
> >> >>>
> >> >>
> >> >
> >> >
> >> >
> >> > --
> >> > Claus Ibsen
> >> > Apache Camel Committer
> >> >
> >> > Open Source Integration: http://fusesource.com
> >> > Blog: http://davsclaus.blogspot.com/
> >> > Twitter: http://twitter.com/davsclaus
> >> >
> >>
> >>
> >>
> >> --
> >> Claus Ibsen
> >> Apache Camel Committer
> >>
> >> Open Source Integration: http://fusesource.com
> >> Blog: http://davsclaus.blogspot.com/
> >> Twitter: http://twitter.com/davsclaus
> >>
> >
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
Hi
You should *not* route after your custom failover processor. You
custom failover processor should be the end of the route (eg no more
.to after your processor).
On Fri, May 15, 2009 at 11:05 AM, Nasim Anza <na...@googlemail.com> wrote:
> Hi,
>
> I’ve tried this solution:
> I started by developing a processor that loops on URIs until getting a valid
> answer.
> The only problem is my route is interrupted at the end of the first
> processing, so no way to pass from first block (addressA) to next block
> (AddressB).
>
> The process() method loops on all URI until getting the valid URI. This
> works but after that I got a fatal error and the route flow was interrupted.
> Below the error I got on ServiceMix console:
>
> ----------------
>
> FATAL - DeadLetterChannel - Failed delivery for exchangeId:
> ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
> sendTo(Endpoint[direct:deadLetterChannel])
> 15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain doIntercept
> INFO: Interceptor has thrown exception, unwinding now
> org.apache.xerces.dom.TextImpl
>
> ----------------
>
> Here is my Camel route:
>
> * //Declare Deadletter processor*
>
> *errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
> *
>
> * //Declare global exception*
>
> *onException(Exception.class).maximumRedeliveries(5) //5 : because I have 5
> address maximum to call*
>
> *final Processor myprocessor() = new Processor(Exchange exchange) throws
> Exception{*
> **
>
> *ProducerTemplate<Exchange> template
> exchange.getContext().createProducerTemplate();
> String uri = exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
> *
>
> *//This method returns the valid list depending on the current http URI*
>
> *List<Strig> uris = getUriList(uri);*
>
> *for (String uri : uris) {*
>
> * try {*
>
> * template.send(uri, exchange);*
>
> * } catch (Exception e) {*
>
> * exchange.setExceptipn(e);*
>
> * }*
>
> * if (exchange.getException() == null) {*
>
> * return;
> }
> }
> }*
>
> * *
>
> *from("direct:endpointA")
> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> .process(myUrlLookerProcessor())
> .to("direct:endPointB")*
>
> *from("direct:endpointB")
> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> .process(myUrlLookerProcessor())
> .to("direct:endPointC")*
>
> *
> from("direct:endPointC")
> .to("xquery:response.xml");*
>
> *from("direct:letter")
> .to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
>
>
>
> Thanks in advance for help.
>
> Nasmo
>
>
> On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <cl...@gmail.com> wrote:
>
>> Hi
>>
>> BTW You can also always just use a Processor and implement the
>> failover logic yourself as pure Java with try .. catch and use the
>> ProducerTemplate to send the exchange to the endpoint based on the
>> URI.
>>
>> Something like
>> ProducerTemplate template = // get it from CamelContext and get it once
>> List<Strig> uris = ...
>>
>> for (String uri : uris) {
>> try {
>> template.send(uri, exchange);
>> } catch (Exception e) {
>> exchange.setExceptipn(e);
>> }
>> if (exchange.getException() == null) {
>> return;
>> }
>> }
>>
>>
>> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <cl...@gmail.com>
>> wrote:
>> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <na...@googlemail.com>
>> wrote:
>> >> Thanks Claus for your quick answer.
>> >>
>> >> I downloaded the source of camel 2.0 and I looked at the
>> >> FailOverLoadBalancer class. I think that this could answer to my
>> question.
>> >> I've tried to adapt the code to my requirement but I have some questions
>> >> about the list of processors used in this class :
>> >>
>> >> 1. I don't know How to create or initialize the processors used for
>> >> balancing user requests ?
>> >>
>> >> 2. Shall I create a camel Processor for each HTTP URL ?
>> >>
>> >> 3. Whait is the syntaxe (maybe something like new Processor(myHttpURL))
>> > Hi
>> >
>> > Yeah there is no nice DSL support for it and the loadbalance() DSL
>> > does not have a nice support for custom load balancer.
>> > So that is something we might need to improve in the future. I have to
>> > remember this thread.
>> >
>> > So what you basically have to do is to add your custom load balancer
>> > as a processor, so use the process() DSL.
>> >
>> > And your custom fail over loadbalancer can accept a list of endpoints
>> > to select among. You can wrap an endpoint to a processor
>> > with the SendToProcessor.
>> >
>> > Something like this
>> >
>> > MyFailover my = new MyFailoverProcessor()l;
>> > my.addEndpoint("foo");
>> > my.addEndpoint("bar");
>> >
>> >
>> > And in the route DSL you just route to your processor
>> > from(x).process(my);
>> >
>> > And in the addEndpoint method you add the endpoint by wrapping it with
>> > a SendToProcessor so you can add it to the LoadBalancerSupport class.
>> >
>> > See how it goes and ask again tomorrow when I am back in the office
>> > and can better work. As I sit now with the laptop in the living room.
>> >
>> >
>> >>
>> >> Thanks for help
>> >>
>> >>
>> >>
>> >>
>> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <cl...@gmail.com>
>> wrote:
>> >>
>> >>> Hi
>> >>>
>> >>> There are load balancers with Camel
>> >>> http://camel.apache.org/load-balancer.html
>> >>>
>> >>> And there is a failover load balancer as well that can do a simple try
>> >>> the next endpoint until success kinda style.
>> >>> Its a bit primitive at the moment and we would like to improve that in
>> >>> the future.
>> >>>
>> >>> But it allows you to implement your own load balancer and do your
>> >>> strategy how you like it.
>> >>>
>> >>> Any feedback for features that could be needed for a more advanced
>> >>> failover loadbalancer is much welcome.
>> >>>
>> >>> Ah the failover loadbalancer is not part of Camel 1.x. But you can
>> >>> check the source code for 2.0 and create your own kinda to use in 1.x.
>> >>>
>> >>>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>> >>>
>> >>>
>> >>>
>> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <nasmo2009@googlemail.com
>> >
>> >>> wrote:
>> >>> > Hi,
>> >>> >
>> >>> > I would like to implement the following route with Camel 1.6 :
>> >>> >
>> >>> > from("direct:endpointA")
>> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> >>> > .to("http://xxxxxx")
>> >>> > .to("direct:endPointB")
>> >>> >
>> >>> > from("direct:endpointB")
>> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>> >>> > .to("http://xxxxxx")
>> >>> > .to("direct:endPointC")
>> >>> >
>> >>> > from("direct:endPointC")
>> >>> > .to("xquery:response.xml");
>> >>> >
>> >>> > This route works fine if both URLs : http://myAddressA and
>> >>> > http://myAddressBare accessible and no error occurs during the
>> >>> > invocation.
>> >>> > Unfortunately, sometimes these services become unreachable and I
>> would
>> >>> like
>> >>> > to try other URLs until getting valid answer:
>> >>> >
>> >>> > If an exception happens when calling the URL http:/:myAddressA, I
>> would
>> >>> like
>> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until getting
>> valid
>> >>> > HTTP response.
>> >>> > The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
>> >>> >
>> >>> > With java this could be simply coded like following :
>> >>> >
>> >>> > try
>> >>> > {
>> >>> > call_http(myAddressA)
>> >>> > }
>> >>> > catch(Throwable th)
>> >>> > {
>> >>> > try
>> >>> > {
>> >>> > call_http(myAddressA1)
>> >>> > }
>> >>> > catch(Exception x)
>> >>> > {
>> >>> > //Call addressA2
>> >>> > ....
>> >>> > }
>> >>> > }
>> >>> >
>> >>> > I've tried the onException() mechanism and the deadLetterChannel
>> >>> processor
>> >>> > but I never get working my route.
>> >>> >
>> >>>
>> >>>
>> >>>
>> >>> --
>> >>> Claus Ibsen
>> >>> Apache Camel Committer
>> >>>
>> >>> Open Source Integration: http://fusesource.com
>> >>> Blog: http://davsclaus.blogspot.com/
>> >>> Twitter: http://twitter.com/davsclaus
>> >>>
>> >>
>> >
>> >
>> >
>> > --
>> > Claus Ibsen
>> > Apache Camel Committer
>> >
>> > Open Source Integration: http://fusesource.com
>> > Blog: http://davsclaus.blogspot.com/
>> > Twitter: http://twitter.com/davsclaus
>> >
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Nasim Anza <na...@googlemail.com>.
Hi,
I’ve tried this solution:
I started by developing a processor that loops on URIs until getting a valid
answer.
The only problem is my route is interrupted at the end of the first
processing, so no way to pass from first block (addressA) to next block
(AddressB).
The process() method loops on all URI until getting the valid URI. This
works but after that I got a fatal error and the route flow was interrupted.
Below the error I got on ServiceMix console:
----------------
FATAL - DeadLetterChannel - Failed delivery for exchangeId:
ID-ROME/1982-1242375956166/0-4. Handled by the failure processor:
sendTo(Endpoint[direct:deadLetterChannel])
15 mai 2009 09:32:37 org.apache.cxf.phase.PhaseInterceptorChain doIntercept
INFO: Interceptor has thrown exception, unwinding now
org.apache.xerces.dom.TextImpl
----------------
Here is my Camel route:
* //Declare Deadletter processor*
*errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
*
* //Declare global exception*
*onException(Exception.class).maximumRedeliveries(5) //5 : because I have 5
address maximum to call*
*final Processor myprocessor() = new Processor(Exchange exchange) throws
Exception{*
**
*ProducerTemplate<Exchange> template
exchange.getContext().createProducerTemplate();
String uri = exchange.getIn().getHeader(HttpProducer.**HTTP_URI).toString();
*
*//This method returns the valid list depending on the current http URI*
*List<Strig> uris = getUriList(uri);*
*for (String uri : uris) {*
* try {*
* template.send(uri, exchange);*
* } catch (Exception e) {*
* exchange.setExceptipn(e);*
* }*
* if (exchange.getException() == null) {*
* return;
}
}
}*
* *
*from("direct:endpointA")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
.process(myUrlLookerProcessor())
.to("direct:endPointB")*
*from("direct:endpointB")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
.process(myUrlLookerProcessor())
.to("direct:endPointC")*
*
from("direct:endPointC")
.to("xquery:response.xml");*
*from("direct:letter")
.to("log:dead_letterChannel?showHeaders=true&level=DEBUG");*
Thanks in advance for help.
Nasmo
On Fri, May 15, 2009 at 9:41 AM, Claus Ibsen <cl...@gmail.com> wrote:
> Hi
>
> BTW You can also always just use a Processor and implement the
> failover logic yourself as pure Java with try .. catch and use the
> ProducerTemplate to send the exchange to the endpoint based on the
> URI.
>
> Something like
> ProducerTemplate template = // get it from CamelContext and get it once
> List<Strig> uris = ...
>
> for (String uri : uris) {
> try {
> template.send(uri, exchange);
> } catch (Exception e) {
> exchange.setExceptipn(e);
> }
> if (exchange.getException() == null) {
> return;
> }
> }
>
>
> On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <cl...@gmail.com>
> wrote:
> > On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <na...@googlemail.com>
> wrote:
> >> Thanks Claus for your quick answer.
> >>
> >> I downloaded the source of camel 2.0 and I looked at the
> >> FailOverLoadBalancer class. I think that this could answer to my
> question.
> >> I've tried to adapt the code to my requirement but I have some questions
> >> about the list of processors used in this class :
> >>
> >> 1. I don't know How to create or initialize the processors used for
> >> balancing user requests ?
> >>
> >> 2. Shall I create a camel Processor for each HTTP URL ?
> >>
> >> 3. Whait is the syntaxe (maybe something like new Processor(myHttpURL))
> > Hi
> >
> > Yeah there is no nice DSL support for it and the loadbalance() DSL
> > does not have a nice support for custom load balancer.
> > So that is something we might need to improve in the future. I have to
> > remember this thread.
> >
> > So what you basically have to do is to add your custom load balancer
> > as a processor, so use the process() DSL.
> >
> > And your custom fail over loadbalancer can accept a list of endpoints
> > to select among. You can wrap an endpoint to a processor
> > with the SendToProcessor.
> >
> > Something like this
> >
> > MyFailover my = new MyFailoverProcessor()l;
> > my.addEndpoint("foo");
> > my.addEndpoint("bar");
> >
> >
> > And in the route DSL you just route to your processor
> > from(x).process(my);
> >
> > And in the addEndpoint method you add the endpoint by wrapping it with
> > a SendToProcessor so you can add it to the LoadBalancerSupport class.
> >
> > See how it goes and ask again tomorrow when I am back in the office
> > and can better work. As I sit now with the laptop in the living room.
> >
> >
> >>
> >> Thanks for help
> >>
> >>
> >>
> >>
> >> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <cl...@gmail.com>
> wrote:
> >>
> >>> Hi
> >>>
> >>> There are load balancers with Camel
> >>> http://camel.apache.org/load-balancer.html
> >>>
> >>> And there is a failover load balancer as well that can do a simple try
> >>> the next endpoint until success kinda style.
> >>> Its a bit primitive at the moment and we would like to improve that in
> >>> the future.
> >>>
> >>> But it allows you to implement your own load balancer and do your
> >>> strategy how you like it.
> >>>
> >>> Any feedback for features that could be needed for a more advanced
> >>> failover loadbalancer is much welcome.
> >>>
> >>> Ah the failover loadbalancer is not part of Camel 1.x. But you can
> >>> check the source code for 2.0 and create your own kinda to use in 1.x.
> >>>
> >>>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
> >>>
> >>>
> >>>
> >>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <nasmo2009@googlemail.com
> >
> >>> wrote:
> >>> > Hi,
> >>> >
> >>> > I would like to implement the following route with Camel 1.6 :
> >>> >
> >>> > from("direct:endpointA")
> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> >>> > .to("http://xxxxxx")
> >>> > .to("direct:endPointB")
> >>> >
> >>> > from("direct:endpointB")
> >>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> >>> > .to("http://xxxxxx")
> >>> > .to("direct:endPointC")
> >>> >
> >>> > from("direct:endPointC")
> >>> > .to("xquery:response.xml");
> >>> >
> >>> > This route works fine if both URLs : http://myAddressA and
> >>> > http://myAddressBare accessible and no error occurs during the
> >>> > invocation.
> >>> > Unfortunately, sometimes these services become unreachable and I
> would
> >>> like
> >>> > to try other URLs until getting valid answer:
> >>> >
> >>> > If an exception happens when calling the URL http:/:myAddressA, I
> would
> >>> like
> >>> > to attempt other URLs : myAddressA1, myAddressA2, ...until getting
> valid
> >>> > HTTP response.
> >>> > The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
> >>> >
> >>> > With java this could be simply coded like following :
> >>> >
> >>> > try
> >>> > {
> >>> > call_http(myAddressA)
> >>> > }
> >>> > catch(Throwable th)
> >>> > {
> >>> > try
> >>> > {
> >>> > call_http(myAddressA1)
> >>> > }
> >>> > catch(Exception x)
> >>> > {
> >>> > //Call addressA2
> >>> > ....
> >>> > }
> >>> > }
> >>> >
> >>> > I've tried the onException() mechanism and the deadLetterChannel
> >>> processor
> >>> > but I never get working my route.
> >>> >
> >>>
> >>>
> >>>
> >>> --
> >>> Claus Ibsen
> >>> Apache Camel Committer
> >>>
> >>> Open Source Integration: http://fusesource.com
> >>> Blog: http://davsclaus.blogspot.com/
> >>> Twitter: http://twitter.com/davsclaus
> >>>
> >>
> >
> >
> >
> > --
> > Claus Ibsen
> > Apache Camel Committer
> >
> > Open Source Integration: http://fusesource.com
> > Blog: http://davsclaus.blogspot.com/
> > Twitter: http://twitter.com/davsclaus
> >
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
Hi
BTW You can also always just use a Processor and implement the
failover logic yourself as pure Java with try .. catch and use the
ProducerTemplate to send the exchange to the endpoint based on the
URI.
Something like
ProducerTemplate template = // get it from CamelContext and get it once
List<Strig> uris = ...
for (String uri : uris) {
try {
template.send(uri, exchange);
} catch (Exception e) {
exchange.setExceptipn(e);
}
if (exchange.getException() == null) {
return;
}
}
On Thu, May 14, 2009 at 6:19 PM, Claus Ibsen <cl...@gmail.com> wrote:
> On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <na...@googlemail.com> wrote:
>> Thanks Claus for your quick answer.
>>
>> I downloaded the source of camel 2.0 and I looked at the
>> FailOverLoadBalancer class. I think that this could answer to my question.
>> I've tried to adapt the code to my requirement but I have some questions
>> about the list of processors used in this class :
>>
>> 1. I don't know How to create or initialize the processors used for
>> balancing user requests ?
>>
>> 2. Shall I create a camel Processor for each HTTP URL ?
>>
>> 3. Whait is the syntaxe (maybe something like new Processor(myHttpURL))
> Hi
>
> Yeah there is no nice DSL support for it and the loadbalance() DSL
> does not have a nice support for custom load balancer.
> So that is something we might need to improve in the future. I have to
> remember this thread.
>
> So what you basically have to do is to add your custom load balancer
> as a processor, so use the process() DSL.
>
> And your custom fail over loadbalancer can accept a list of endpoints
> to select among. You can wrap an endpoint to a processor
> with the SendToProcessor.
>
> Something like this
>
> MyFailover my = new MyFailoverProcessor()l;
> my.addEndpoint("foo");
> my.addEndpoint("bar");
>
>
> And in the route DSL you just route to your processor
> from(x).process(my);
>
> And in the addEndpoint method you add the endpoint by wrapping it with
> a SendToProcessor so you can add it to the LoadBalancerSupport class.
>
> See how it goes and ask again tomorrow when I am back in the office
> and can better work. As I sit now with the laptop in the living room.
>
>
>>
>> Thanks for help
>>
>>
>>
>>
>> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <cl...@gmail.com> wrote:
>>
>>> Hi
>>>
>>> There are load balancers with Camel
>>> http://camel.apache.org/load-balancer.html
>>>
>>> And there is a failover load balancer as well that can do a simple try
>>> the next endpoint until success kinda style.
>>> Its a bit primitive at the moment and we would like to improve that in
>>> the future.
>>>
>>> But it allows you to implement your own load balancer and do your
>>> strategy how you like it.
>>>
>>> Any feedback for features that could be needed for a more advanced
>>> failover loadbalancer is much welcome.
>>>
>>> Ah the failover loadbalancer is not part of Camel 1.x. But you can
>>> check the source code for 2.0 and create your own kinda to use in 1.x.
>>>
>>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>>>
>>>
>>>
>>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <na...@googlemail.com>
>>> wrote:
>>> > Hi,
>>> >
>>> > I would like to implement the following route with Camel 1.6 :
>>> >
>>> > from("direct:endpointA")
>>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>>> > .to("http://xxxxxx")
>>> > .to("direct:endPointB")
>>> >
>>> > from("direct:endpointB")
>>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>>> > .to("http://xxxxxx")
>>> > .to("direct:endPointC")
>>> >
>>> > from("direct:endPointC")
>>> > .to("xquery:response.xml");
>>> >
>>> > This route works fine if both URLs : http://myAddressA and
>>> > http://myAddressBare accessible and no error occurs during the
>>> > invocation.
>>> > Unfortunately, sometimes these services become unreachable and I would
>>> like
>>> > to try other URLs until getting valid answer:
>>> >
>>> > If an exception happens when calling the URL http:/:myAddressA, I would
>>> like
>>> > to attempt other URLs : myAddressA1, myAddressA2, ...until getting valid
>>> > HTTP response.
>>> > The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
>>> >
>>> > With java this could be simply coded like following :
>>> >
>>> > try
>>> > {
>>> > call_http(myAddressA)
>>> > }
>>> > catch(Throwable th)
>>> > {
>>> > try
>>> > {
>>> > call_http(myAddressA1)
>>> > }
>>> > catch(Exception x)
>>> > {
>>> > //Call addressA2
>>> > ....
>>> > }
>>> > }
>>> >
>>> > I've tried the onException() mechanism and the deadLetterChannel
>>> processor
>>> > but I never get working my route.
>>> >
>>>
>>>
>>>
>>> --
>>> Claus Ibsen
>>> Apache Camel Committer
>>>
>>> Open Source Integration: http://fusesource.com
>>> Blog: http://davsclaus.blogspot.com/
>>> Twitter: http://twitter.com/davsclaus
>>>
>>
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
On Thu, May 14, 2009 at 4:55 PM, Nasim Anza <na...@googlemail.com> wrote:
> Thanks Claus for your quick answer.
>
> I downloaded the source of camel 2.0 and I looked at the
> FailOverLoadBalancer class. I think that this could answer to my question.
> I've tried to adapt the code to my requirement but I have some questions
> about the list of processors used in this class :
>
> 1. I don't know How to create or initialize the processors used for
> balancing user requests ?
>
> 2. Shall I create a camel Processor for each HTTP URL ?
>
> 3. Whait is the syntaxe (maybe something like new Processor(myHttpURL))
Hi
Yeah there is no nice DSL support for it and the loadbalance() DSL
does not have a nice support for custom load balancer.
So that is something we might need to improve in the future. I have to
remember this thread.
So what you basically have to do is to add your custom load balancer
as a processor, so use the process() DSL.
And your custom fail over loadbalancer can accept a list of endpoints
to select among. You can wrap an endpoint to a processor
with the SendToProcessor.
Something like this
MyFailover my = new MyFailoverProcessor()l;
my.addEndpoint("foo");
my.addEndpoint("bar");
And in the route DSL you just route to your processor
from(x).process(my);
And in the addEndpoint method you add the endpoint by wrapping it with
a SendToProcessor so you can add it to the LoadBalancerSupport class.
See how it goes and ask again tomorrow when I am back in the office
and can better work. As I sit now with the laptop in the living room.
>
> Thanks for help
>
>
>
>
> On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <cl...@gmail.com> wrote:
>
>> Hi
>>
>> There are load balancers with Camel
>> http://camel.apache.org/load-balancer.html
>>
>> And there is a failover load balancer as well that can do a simple try
>> the next endpoint until success kinda style.
>> Its a bit primitive at the moment and we would like to improve that in
>> the future.
>>
>> But it allows you to implement your own load balancer and do your
>> strategy how you like it.
>>
>> Any feedback for features that could be needed for a more advanced
>> failover loadbalancer is much welcome.
>>
>> Ah the failover loadbalancer is not part of Camel 1.x. But you can
>> check the source code for 2.0 and create your own kinda to use in 1.x.
>>
>> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>>
>>
>>
>> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <na...@googlemail.com>
>> wrote:
>> > Hi,
>> >
>> > I would like to implement the following route with Camel 1.6 :
>> >
>> > from("direct:endpointA")
>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
>> > .to("http://xxxxxx")
>> > .to("direct:endPointB")
>> >
>> > from("direct:endpointB")
>> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
>> > .to("http://xxxxxx")
>> > .to("direct:endPointC")
>> >
>> > from("direct:endPointC")
>> > .to("xquery:response.xml");
>> >
>> > This route works fine if both URLs : http://myAddressA and
>> > http://myAddressBare accessible and no error occurs during the
>> > invocation.
>> > Unfortunately, sometimes these services become unreachable and I would
>> like
>> > to try other URLs until getting valid answer:
>> >
>> > If an exception happens when calling the URL http:/:myAddressA, I would
>> like
>> > to attempt other URLs : myAddressA1, myAddressA2, ...until getting valid
>> > HTTP response.
>> > The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
>> >
>> > With java this could be simply coded like following :
>> >
>> > try
>> > {
>> > call_http(myAddressA)
>> > }
>> > catch(Throwable th)
>> > {
>> > try
>> > {
>> > call_http(myAddressA1)
>> > }
>> > catch(Exception x)
>> > {
>> > //Call addressA2
>> > ....
>> > }
>> > }
>> >
>> > I've tried the onException() mechanism and the deadLetterChannel
>> processor
>> > but I never get working my route.
>> >
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Nasim Anza <na...@googlemail.com>.
Thanks Claus for your quick answer.
I downloaded the source of camel 2.0 and I looked at the
FailOverLoadBalancer class. I think that this could answer to my question.
I've tried to adapt the code to my requirement but I have some questions
about the list of processors used in this class :
1. I don't know How to create or initialize the processors used for
balancing user requests ?
2. Shall I create a camel Processor for each HTTP URL ?
3. Whait is the syntaxe (maybe something like new Processor(myHttpURL))
Thanks for help
On Thu, May 14, 2009 at 11:59 AM, Claus Ibsen <cl...@gmail.com> wrote:
> Hi
>
> There are load balancers with Camel
> http://camel.apache.org/load-balancer.html
>
> And there is a failover load balancer as well that can do a simple try
> the next endpoint until success kinda style.
> Its a bit primitive at the moment and we would like to improve that in
> the future.
>
> But it allows you to implement your own load balancer and do your
> strategy how you like it.
>
> Any feedback for features that could be needed for a more advanced
> failover loadbalancer is much welcome.
>
> Ah the failover loadbalancer is not part of Camel 1.x. But you can
> check the source code for 2.0 and create your own kinda to use in 1.x.
>
> https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
>
>
>
> On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <na...@googlemail.com>
> wrote:
> > Hi,
> >
> > I would like to implement the following route with Camel 1.6 :
> >
> > from("direct:endpointA")
> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> > .to("http://xxxxxx")
> > .to("direct:endPointB")
> >
> > from("direct:endpointB")
> > .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> > .to("http://xxxxxx")
> > .to("direct:endPointC")
> >
> > from("direct:endPointC")
> > .to("xquery:response.xml");
> >
> > This route works fine if both URLs : http://myAddressA and
> > http://myAddressBare accessible and no error occurs during the
> > invocation.
> > Unfortunately, sometimes these services become unreachable and I would
> like
> > to try other URLs until getting valid answer:
> >
> > If an exception happens when calling the URL http:/:myAddressA, I would
> like
> > to attempt other URLs : myAddressA1, myAddressA2, ...until getting valid
> > HTTP response.
> > The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
> >
> > With java this could be simply coded like following :
> >
> > try
> > {
> > call_http(myAddressA)
> > }
> > catch(Throwable th)
> > {
> > try
> > {
> > call_http(myAddressA1)
> > }
> > catch(Exception x)
> > {
> > //Call addressA2
> > ....
> > }
> > }
> >
> > I've tried the onException() mechanism and the deadLetterChannel
> processor
> > but I never get working my route.
> >
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
Re: Calling dynamically multiple http endpoints
Posted by Claus Ibsen <cl...@gmail.com>.
Hi
There are load balancers with Camel
http://camel.apache.org/load-balancer.html
And there is a failover load balancer as well that can do a simple try
the next endpoint until success kinda style.
Its a bit primitive at the moment and we would like to improve that in
the future.
But it allows you to implement your own load balancer and do your
strategy how you like it.
Any feedback for features that could be needed for a more advanced
failover loadbalancer is much welcome.
Ah the failover loadbalancer is not part of Camel 1.x. But you can
check the source code for 2.0 and create your own kinda to use in 1.x.
https://svn.apache.org/repos/asf/camel/trunk/camel-core/src/main/java/org/apache/camel/processor/loadbalancer/
On Thu, May 14, 2009 at 11:45 AM, Nasim Anza <na...@googlemail.com> wrote:
> Hi,
>
> I would like to implement the following route with Camel 1.6 :
>
> from("direct:endpointA")
> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
> .to("http://xxxxxx")
> .to("direct:endPointB")
>
> from("direct:endpointB")
> .setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
> .to("http://xxxxxx")
> .to("direct:endPointC")
>
> from("direct:endPointC")
> .to("xquery:response.xml");
>
> This route works fine if both URLs : http://myAddressA and
> http://myAddressBare accessible and no error occurs during the
> invocation.
> Unfortunately, sometimes these services become unreachable and I would like
> to try other URLs until getting valid answer:
>
> If an exception happens when calling the URL http:/:myAddressA, I would like
> to attempt other URLs : myAddressA1, myAddressA2, ...until getting valid
> HTTP response.
> The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
>
> With java this could be simply coded like following :
>
> try
> {
> call_http(myAddressA)
> }
> catch(Throwable th)
> {
> try
> {
> call_http(myAddressA1)
> }
> catch(Exception x)
> {
> //Call addressA2
> ....
> }
> }
>
> I've tried the onException() mechanism and the deadLetterChannel processor
> but I never get working my route.
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Calling dynamically multiple http endpoints
Posted by Nasim Anza <na...@googlemail.com>.
Sorry my question was incomplete. Below the complete message:
----------------
Hi,
I would like to implement the following route with Camel 1.6 :
from("direct:endpointA")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressA")
.to("http://xxxxxx")
.to("direct:endPointB")
from("direct:endpointB")
.setHeader(HttpProducer.HTTP_URI).simple("http://myAddressB")
.to("http://xxxxxx")
.to("direct:endPointC")
from("direct:endPointC")
.to("xquery:response.xml");
This route works fine if both URLs : http://myAddressA and
http://myAddressBare accessible and no error occurs during the
invocation.
Unfortunately, sometimes these services become unreachable and I would like
to try other URLs until getting valid answer:
If an exception happens when calling the URL http:/:myAddressA, I would like
to attempt other URLs : myAddressA1, myAddressA2, ...until getting valid
HTTP response.
The same thing with myAddressB ==> myAddressB1, myAddressB2, ...
With java this could be simply coded like following :
try
{
call_http(myAddressA)
}
catch(Throwable th)
{
try
{
call_http(myAddressA1)
}
catch(Exception x)
{
//Call addressA2
....
}
}
I've tried the Camel onException() mechanism and the deadLetterChannel EIP
processor but I never get working my route.
Below the code I've tried :
//Declare Deadletter processor
errorHandler(deadLetterChannel("direct:letter").onRedelivery(myProcessor));
//Declare global exception
onException(Exception.class).maximumRedeliveries(5) //5 : because I have 5
address maximum to call
final Processor myProcessor = new Processor()
{
public void process(Exchange exchange) throws Exception {
try
{
String uri =
exchange.getIn().getHeader(HttpProducer.HTTP_URI).toString();
if(uri.equals("http://myAddressA"))
uri="http://myAddressA1";
else if(uri.equals("http://myAddressA1"))
uri="http://myAddressA2";
else if(uri.equals("http://myAddressA2"))
uri="http://myAddressA3";
//etc
exchange.getIn().setHeader(HttpProducer.HTTP_URI, uri);
}
catch(Throwable error)
{
error.printStackTrace);
}
}
Your help will be appreciated.
Thanks