Re: Mixed Messages and Resequencer

[Hervé BARRAULT <he...@gmail.com>]

Hi,
I think using camel like this :

Define a standard route (which uses a "dynamic" content based router).

from("cxf:myEndpoint").process(myProcessor).to(header("target").toString());

header("target").toString() => seda:<<streamType>>

And a template which i should instantiate for each new <<stream type>> such
as

from("seda:<<streamType>>").stream().capacity(5000).timeout(500L).process(myProcessor2);

Is it a good way of using camel for the resequencing of multiple streams ?.

I know that i can loose my messages until i manage it in myProcessor2.

Regards
Hervé


On Wed, Feb 29, 2012 at 1:18 PM, Hervé BARRAULT <he...@gmail.com>wrote:

> Hi,
>
> thanks for answer.
> the idea was to use a stream resequencer. In main case messages will be in
> right order but sometimes i could have an inversion so with stream
> resequencer i will not block these messages.
>
> But i would resequence n different streams as I have no logic order
> between A and B and ...
>
> So i would define n stream resequencers [to avoid blocking resequencing of
> all stream if one has a gap].
>
> But i don't see if the resequencer is adapted for this particular case.
>
> I could perhaps implement a complex comparator but i don't think being
> able to handle n independent streams correctly.
>
> Regards
> Hervé
>
>
> On Wed, Feb 29, 2012 at 11:23 AM, Claus Ibsen <cl...@gmail.com>wrote:
>
>> Hi
>>
>> The resequencer EIP works in 2 modes
>> - a) batch
>> - b) streaming
>>
>> Ad a)
>> uses a java.util.Comparator to compare to know in which order the
>> messages should be.
>>
>> You can configure such a comparator using something a like
>> org.apache.camel.util.ExpressionComparator, which shows you how
>> to grab the [A,1] from the message, and then you can do custom java
>> code how to compare that. So you can code that [A,1] comes before
>> [B,1] etc.
>>
>> Then you ought to be able to resequence in a mix with [A,1] and [B,1] etc.
>>
>> The batch mode will emit messages in batches after either a timeout,
>> or a certain size has been hit.
>>
>> Ad b)
>> The streaming mode runs in a continues stream, but it requires that
>> there is *no* gaps. And by default it only offers a Long based
>> comparator.
>> You will have to implement your custom comparator which is a:
>> org.apache.camel.processor.resequencer.ExpressionResultComparator
>>
>> And then you need to implement logic to tell which is the prev / next
>> exepected message, so the resequencer knows if it got the messages,
>> so there is no gaps, and then can emit the messages.
>>
>>
>>
>> Mind that the resequencer is purely memory based, it does not offer a
>> persistent store, and cannot remember its state. So if you restart or
>> server crashes, the messages will be lost.
>>
>>
>>
>>
>>
>> On Wed, Feb 29, 2012 at 9:45 AM, Hervé BARRAULT
>> <he...@gmail.com> wrote:
>> > Hi,
>> >
>> > I would order messages in a route
>> > I think the resequencer is the right EIP for this but i have some
>> > difficulties to see how to apply it in my case.
>> >
>> > Classical Behavior :
>> > input : M[1] M[3] M[2] M[4] , the output will be M[1] M[2] M[3] M[4].
>> >
>> > In my case i will have the following entry :
>> >
>> > M[A,1] M[B,1] M[B,2] M[A,4] M[A,5] M[B,4] M[A,3] M[B,3] M[A,2], M[B,5]
>> >
>> > I would have at the end :
>> > M[A,1] M[A,2] M[A,3] M[A,4] M[A,5]
>> > M[B,1] M[B,2] M[B,3] M[B,4] M[B,5]
>> >
>> > We can define one route which separate "A" and "B" messages [basic
>> message
>> > router].
>> >
>> > Then two routes (one for "A", one for "B" which do the resequencing
>> [basic
>> > resequencer] ).
>> >
>> > If A and B are defined before runtime it's simple.
>> > If A and B are not fixed but is a dynamic list, i can't see how to
>> > implement this.
>> >
>> > Is there a way to have this behavior ?
>> >
>> > Thanks for answers
>> >
>> > Regards
>>
>>
>>
>> --
>> Claus Ibsen
>> -----------------
>> FuseSource
>> Email: cibsen@fusesource.com
>> Web: http://fusesource.com
>> Twitter: davsclaus, fusenews
>> Blog: http://davsclaus.blogspot.com/
>> Author of Camel in Action: http://www.manning.com/ibsen/
>>
>
>

Re: Mixed Messages and Resequencer

[Hervé BARRAULT <he...@gmail.com>]

Hi, what is the better way to create a MultiStreamResequencer ?

I would like to :
    Replace the ResequencerEngine<Exchange> engine by a map (indexed by
stream) [also Delivery delivery].
    Add an Expression to choose the right Resequencer engine.
    Add a way to close a resequencer at the end of the stream.

It could be seen as managing "a JMSXGroupId" in resequencer.

Regards
Hervé