Hi Jakub
Have you had some time recently to work with the project ?
FYI, JAX-RS 2.0 introduces
http://jax-rs-spec.java.net/nonav/2.0-SNAPSHOT/apidocs/javax/ws/rs/container/ResourceContext.html
I haven't typed and code for it, but I can imagine GuiceResourceContext
being introduced
Cheers, Sergey
On 30/04/12 18:54, Jakub Bochenski wrote:
Hi Sergey,
I was actually on holidays so I didn't mind the delay.
Taking your anwser into account I will try to do it by injecting
context instances into those subresources that are provided by Guice.
Will you acept a patch to trunk refactoring the JaxRsInvoker, so that
the conditions for injection can be overridden without copy-pasting
code?
I have also taken a closer look at Guice scopes API and I think it
will actually be rather simple to inject Guice-managed objects with
context dependencies.
While most of the time you would probably be better off just declaring
them in the resource objects and passing them explicitly via method
calls, there are a couple of use cases where this might become useful.
One example I can think of is the Accept-Language header.
So later I plan to make the valid-for-singletons context objects and
some per-request objects (at first probably path and header params, as
I don't think doing that to query/form params would make sense)
available in Guice.
Best regards,
Jakub Bocheński
On Wed, Apr 25, 2012 at 1:37 PM, Sergey Beryozkin-5 [via CXF]
<[email protected]> wrote:
Hi Jakub
Sorry for a delay,
On 19/04/12 13:53, Jakub Bochenski wrote:
Sorry, I accidentally sent the email before I finished writing.
As for manually creating/ injecting subresources you would have to
inject guice providers for them (code bloat) plus you are never sure
that the creator didn't forget to call all the needed setters.
Compare my previous example to:
@Path("foo");
abstract class ResourceA {
final Provider<ResourceB> guiceProvider;
ResourceA(Provider<ResourceB> guiceProvider){
this.guiceProvider = guiceProvider;
}
@Path("bar")
ResourceB getSubResource(){
ResourceB resource = provider.get();
resource.setLanguage(this.lang);
resource.setSometing(this.aa);
return resource;
}
}
This does the same but IMHO is much less clear.
Agreed. I think subresource handlers will not always be injected and
often will be created based on some application-specific logic, example,
say an OSGI Service gets registered and it gets recognized as a valid
handler, etc...
So do you think implementing this by modifying the aforementioned
block in JaxRsInvoker to inject if resource is a root resource *or* is
"guice lookup" resource would be a good approach?
As far as managing the injection of contexts into subresource handlers
which are themselves injected or managed by proxies using a 'lookup'
method seems like the only reasonable approach to me.
Thanks, Sergey
Best regards,
Jakub Bochenski
2012/4/19 Jakub Bocheński<[hidden email]>:
Hi Sergey,
the abstract qualifier is a design decision really - I prefer it that
way, because you are more sure then that the developer wanted the
method to be implemented by the runtime. Also if you need to create
the class manually you can always implement it inline (I think its
actually beneficial, because testing code stays in test classes).
Still I think it's quite a minor detail that can be implemeted either
way is found more suitable in the end.
As for manually creating/ injecting subresources you would have to
inject guice providers for them (code bloat) plus you are never sure
that the creator didn't forget to call all the needed setters.
Compare my previous example to:
@Path("foo");
abstract class ResourceA {
final Provider<ResourceB> guiceProvider;
ResourceA(Provider<ResourceB> guiceProvider){
this.guiceProvider = guiceProvider;
}
@Path("bar")
ResourceB getSubResource(){
}
}
Jakub Bocheński
On Thu, Apr 19, 2012 at 2:08 PM, Sergey Beryozkin-5 [via CXF]
<[hidden email]> wrote:
Hi Jakub
On 19/04/12 12:50, Jakub Bochenski wrote:
Hi Sergey,
sorry - apparently I wasn't clear enough last time.
I understand your concerns, but what I'd like to support is this:
@Path("foo");
abstract class ResourceA {
@Path("bar")
abstract ResourceB getSubResource();
}
Now the runtime would implement the method using the bytecode
generation (thats what I meant by refering to Spring lookup-method
injection), so it will have control over the resource lifecycle.
The implementation would simply request an appropriate CXF
ResourceProvider from Guice and would be able to do all the
neccessary management.
I understand now, thanks, I'm not entirely sure I'd want to code my root
resource class with 'abstract' qualifiers though, I see that in Spring
the lookup methods can be concrete, no-ops really. I mean I'm not sure
why would I not want to simply add setters on the subresource handlers
to manually pass the contexts from the root resource to the
subresources... That said, if Guice could help with the proper
injection, then why not :-)
Cheers, Sergey
Best regards,
Jakub Bocheński
On Thu, Apr 19, 2012 at 1:27 PM, Sergey Beryozkin-5 [via CXF]
<[hidden email]> wrote:
Hi Jakub
On 16/04/12 17:41, Jakub Bochenski wrote:
Hi Sergey,
thanks for the clarification on the subresource injection issue.
However I understand what you mean I think this considerably limits
usefulness of subresources.
For example in the application I'm working on now I only use root
resources because I can't be bothered to manually inject @Context and
@PathParam dependencies.
Too illustrate what I mean consider this two cases:
// Case 1
@Path("foo");
class ResourceA {
@Path("bar")
ResourceB getSubResource();
}
Let me add a sub-case :-)
Case 1.1
@Path("foo");
class ResourceA {
private ResourceB resourceB = new ResourceB();
@Path("bar")
ResourceB getSubResource() {
return resourceB;
}
}
Case 1.1
@Path("foo");
class ResourceA {
@Path("bar")
ResourceB getSubResource() {
return new ResourceB();
}
}
How will the runtime know that ResourceB is thread-safe ? When the
runtime injects into root resources it knows in advance about the
life-cycle of the root resource, it will inject a thread-safe proxy
into
singletons, plain instances into per-request root resources.
It can not know the way the root resource is managing the
sub-resources,
they can be added dynamically, it's impossible to predict, right ?
// Case 2
@Path("foo");
class ResourceA {
}
@Path("foo/bar")
class ResourceB {
}
Both Case 1 and 2 look the same to the end-client, however in Case 1
you have to manually create and inject ResourceB. In Case 2 ResourceB
is managed by CXF, but the parent-child structure is not visible in
the source code.
Can we have something that would work like Case 2 but look more like
Case 1 in the source (i.e. the parent-child relation would be
explicit)?
I'm thinking about implementing something similar to Spring's
"lookup-method" injection. A resource class would have an abstract
sub-resource locator method that would be implemented by Guice thus
allowing Guice/CXF to control the lifecycle.
As for implementation on CXF side I think it could be as simple as
commenting out the "if (cri.isRoot())" on line 129 of JaxRsInvoker.
(Of course I'm not suggesting this as a productive solution, just
pointing out it's not hard to do in principle).
Do you think such a feature would be useful?
As for JAX-RS 2.0 spec a cursory reading unfortunately didn't result
in any useful insights.
Please see my example above on why I'm not sure it can work, what do
you
think ?
Cheers, Sergey
Best regards,
Jakub Bocheński
On Fri, Apr 13, 2012 at 5:37 PM, Sergey Beryozkin-5 [via CXF]
<[hidden email]> wrote:
Hi,
On 13/04/12 14:11, Jakub Bochenski wrote:
Hi Sergey,
I read somewhere JSR-299 reuses some parts of JSR-330, with some
JSR-330
annotations being the same in JSR-299, but most likely I misread
it,
need to catch up, may be Bill would comment :-)
Having a JSR-330 implementation makes implementing JSR-299 easier,
but
I think that's all.
OK
I'd like to ask you to take a look at the configuration
possibilities
available - I've done what I needed for my project, so validating
this
against other use cases or use styles would be a very good thing.
Apart from obvious things (missing JAXRSServerFactoryBean
properties
like interceptors), do you think this DSL lacks something?
I would also appreciate any coments on the syntax - I think it's
pretty clear and concise now, but maybe there is a better way to
name
the methods etc.
Sure I will try to look into is asap, though some delay will be
there.
If someone else has the experience with Guice then please
contribute
the
comments too
Thanks, although I'm even more interested in CXF-centric look than
Guice-centric if you know what I mean.
Please keep enhancing it, I guess we can drop the module to
rt/rs/extensions/guice or /jsr330 at some stage
Yup, I planned to bring this to a more mature state while on google
code, then when I have something that can be called 1.0 version
merge
it into CXF.
This means providing the beforementioned support for missing config
options plus full support for Guice scopes.
One extra feature I'd be interested in implementing is support for
subresource injection.
As far as I know you have to create and "inject" subresource
classes
manually right now.
Before going into this further I'd like to ask you: is it so
because
it's a gap in JAX-RS 1.0 spec or is there some good reason CXF does
not inject @Context dependecies into subresources?
JAX-RS 1.1 might be mentioning it explicitly, can't recall right
now,
but the reason this is not required is that the lifecycle of
subresources is generally managed at the application level. They
could
be singletons or created on every request or only when no suitable
handler is available, you never know and hence the runtime does not
know
too what to inject. If subresource locator is returning an interface
or
even Object then the decision to inject can only be done at the
invocation time which is a problem too...
Finally I plan to read up the JAX-RS 2.0 spec - this might provide
some insight, since it's purpose is to "path" JSR-311 with JSR-330.
Please do, it's still the work in progress, working out the
relationship, but keeping an eye on the progress would definitely be
a
good idea
Cheers, Sergey
Best regards,
Jakub Bochenski
Thanks, Sergey
Best regards,
Jakub Bocheński
On Thu, Apr 12, 2012 at 10:50 PM, Sergey Beryozkin-5 [via CXF]
<[hidden email]> wrote:
Hi Jakub
On 12/04/12 13:27, Jakub Bochenski wrote:
I've started a little project on google code - basically a EDSL
for
configuring CXF Guice-style.
The instances are created (and injected) by Guice and a custom
ResourceProvider is used to plug them into CXF (which let's you
use
all
injection points except constructor).
If you are interested see the details here:
http://code.google.com/p/guice-cxf/
Any suggestions will be appreciated.
The project has a working version although not all CXF features
are
configurable now.
Thank you for this effort
I would be very happy if the CXF team would be interested in
integrating
it
into the core project - please let me know if you do.
I think the Guice integration can be a good feature to have.
Let me ask one question:
What is the relationship between JSR-299, JSR-330, and Guice ?
Would having the Guice integration let CXF claim it supports
JSR-330
or
JSR-299 or both :-) ?
Thanks, Sergey
