The implementation of a simple service routing. WAS: RE: Release Update

["Liu, Jervis" <jl...@iona.com>]

Hi, I've been experimenting a bit on the service routing lately, the result has been put on the wiki: http://cwiki.apache.org/confluence/display/CXF20DOC/Service+Routing. So it works ((I will check in a system test shortly), my main concern though, is that this implementation does not seem to be very "simple", it does require a fair amount of knowledge of CXF internal. Not sure if it is appropriate to expose this to CXF userland. Anyway, I am open to any comments&suggestions.

Thanks,
Jervis

> -----Original Message-----
> From: Dan Diephouse [mailto:dan@envoisolutions.com]
> Sent: 2007?3?17? 3:32
> To: cxf-dev@incubator.apache.org
> Subject: Re: Release Update
> 
> 
> On 3/15/07, Liu, Jervis <jl...@iona.com> wrote:
> >
> >
> >
> > > -----Original Message-----
> > > From: Dan Diephouse [mailto:dan@envoisolutions.com]
> > > Sent: 2007?3?15? 21:44
> > > To: cxf-dev@incubator.apache.org
> > > Subject: Re: Release Update
> > >
> > >
> > > Hi Jervis,
> > >
> > > I wanted to ensure that we can setup an endpoint on a URL 
> and route to
> > > different services based on headers (such as ws-a) or other
> > > logic.  I made a
> > > series of proposals about how to do this a while back, but I
> > > don't think we
> > > ever came to any concrete conclusion.
> > >
> > Ok, I see what you mean. I believe you are referring to 
> this proposal [1].
> > One thing I have not figured out from the proposal yet is 
> how we know the
> > addresses of services to which the routing service is about 
> to redirect?
> > Through some kind of registries or a configuration loaded 
> from a separate
> > file or a WSDL extension.? Once this kind of discussion 
> gets started, I do
> > not see how it can end by the end of this release. Service 
> routing is a huge
> > topic anyway. However we will have much less to worry about 
> if we are not
> > after a complete resolution of service routing. For 
> example, if we only
> > support the routing among different endpoints within the 
> same Destination,
> > would this feature be considered helpful for some certain 
> use cases? Reading
> > your proposal, I believe this is also what you want to do, 
> start from sth
> > simple first. If this is the case, I am ready to get my 
> hands dirty now.
> >
> > BTW, I am in a traveling at the moment, I may not respond 
> in time until I
> > get back to office next Tuesday.
> >
> > [1].
> > 
> http://mail-archives.apache.org/mod_mbox/incubator-cxf-dev/200
612.mbox/%3c7b774c950612021343x513c2783o128a032ba93923bb@mail.gmail.com%3e



Yes, I'm really just concerned about the simple case. Namely being able to
create some type of routing endpoint which routes to other types of
services. My main use cases is versioning of services. Ideally many services
can share the same URL and I can route by headers or the namespace of the
body part.

Regarding how to know what services to route to - I think its up to the user
to write that code. I was kind of envisioning that it'd be an interceptor
that a user writes. We could build something more formal like a registry,
but we would need something low level first :-)

- Dan

-- 
Dan Diephouse
Envoi Solutions
http://envoisolutions.com | http://netzooid.com/blog

Re: The implementation of a simple service routing. WAS: RE: Release Update

[Dan Diephouse <da...@envoisolutions.com>]

Nice work Jervis.

I think we both share a lot of the same concerns about this approach. Some
thoughts:

1. From a CXF point of view an address is typically associated with one
service/endpoint. It seems odd to require people to register each service on
a different endpoint and then have another endpoint which routes between
them. From a conceptual point of view a user wants to associate multiple
services with a single endpoint. Or, in your example, what if the user just
wants to expose the http://localhost:9027/SoapContext/SoapPort endpoint and
not  http://localhost:9027/SoapContext1/SoapPort?

I guess there are a few ways around this. The simplest would be to use some
kind of local service transport which the mediation interceptor could route
with.
Endpoint.publish("service://service1", service1);
Endpoint.publish("service://service2", service2);
Endpoint.publish("http://localhost/myService", routingService);

There is also the means that I outlined in that email that you linked to in
your previous email.

2. Complexity - I think this one is easier to fix. We can create helper
classes to set up the routing. For instance something like this:

XPathRoutingServerFactory service = new XPathRoutingServerFactory();
service.route("/foo/service1', "service://service1");
service.route("/foo/service2', "service://service2");
service.setAddress("http://localhost/myService");
Server server = service.create();

Or it could use Camel (which is looking very cool btw).

Maybe we can a look at making our 1:1 association with Endpoints and
addresses a little looser as I think that would be conceptually a lot
better. I don't really know what all this entails though. I'll try to take a
look into it the next two days.

- Dan

On 3/23/07, Liu, Jervis <jl...@iona.com> wrote:
>
> Hi, I've been experimenting a bit on the service routing lately, the
> result has been put on the wiki:
> http://cwiki.apache.org/confluence/display/CXF20DOC/Service+Routing. So it
> works ((I will check in a system test shortly), my main concern though, is
> that this implementation does not seem to be very "simple", it does require
> a fair amount of knowledge of CXF internal. Not sure if it is appropriate to
> expose this to CXF userland. Anyway, I am open to any comments&suggestions.
>
> Thanks,
> Jervis
>
> > -----Original Message-----
> > From: Dan Diephouse [mailto:dan@envoisolutions.com]
> > Sent: 2007?3?17? 3:32
> > To: cxf-dev@incubator.apache.org
> > Subject: Re: Release Update
> >
> >
> > On 3/15/07, Liu, Jervis <jl...@iona.com> wrote:
> > >
> > >
> > >
> > > > -----Original Message-----
> > > > From: Dan Diephouse [mailto:dan@envoisolutions.com]
> > > > Sent: 2007?3?15? 21:44
> > > > To: cxf-dev@incubator.apache.org
> > > > Subject: Re: Release Update
> > > >
> > > >
> > > > Hi Jervis,
> > > >
> > > > I wanted to ensure that we can setup an endpoint on a URL
> > and route to
> > > > different services based on headers (such as ws-a) or other
> > > > logic.  I made a
> > > > series of proposals about how to do this a while back, but I
> > > > don't think we
> > > > ever came to any concrete conclusion.
> > > >
> > > Ok, I see what you mean. I believe you are referring to
> > this proposal [1].
> > > One thing I have not figured out from the proposal yet is
> > how we know the
> > > addresses of services to which the routing service is about
> > to redirect?
> > > Through some kind of registries or a configuration loaded
> > from a separate
> > > file or a WSDL extension.? Once this kind of discussion
> > gets started, I do
> > > not see how it can end by the end of this release. Service
> > routing is a huge
> > > topic anyway. However we will have much less to worry about
> > if we are not
> > > after a complete resolution of service routing. For
> > example, if we only
> > > support the routing among different endpoints within the
> > same Destination,
> > > would this feature be considered helpful for some certain
> > use cases? Reading
> > > your proposal, I believe this is also what you want to do,
> > start from sth
> > > simple first. If this is the case, I am ready to get my
> > hands dirty now.
> > >
> > > BTW, I am in a traveling at the moment, I may not respond
> > in time until I
> > > get back to office next Tuesday.
> > >
> > > [1].
> > >
> > http://mail-archives.apache.org/mod_mbox/incubator-cxf-dev/200
> 612.mbox/%3c7b774c950612021343x513c2783o128a032ba93923bb@mail.gmail.com%3e
>
>
>
> Yes, I'm really just concerned about the simple case. Namely being able to
> create some type of routing endpoint which routes to other types of
> services. My main use cases is versioning of services. Ideally many
> services
> can share the same URL and I can route by headers or the namespace of the
> body part.
>
> Regarding how to know what services to route to - I think its up to the
> user
> to write that code. I was kind of envisioning that it'd be an interceptor
> that a user writes. We could build something more formal like a registry,
> but we would need something low level first :-)
>
> - Dan
>
> --
> Dan Diephouse
> Envoi Solutions
> http://envoisolutions.com | http://netzooid.com/blog
>



-- 
Dan Diephouse
Envoi Solutions
http://envoisolutions.com | http://netzooid.com/blog