A Unit Testing + Guice Question

[Devan Goodwin]

I would like to be able to have an individual unit test configure the
Principal object that Guice will inject into the component I'm
testing. Currently this is done in Guice Modules and thus doesn't
really allow you to change bindings on a test by test basis that I can
find. Anyone know of a way?

I've got a workable solution but it's not real pretty, bind
Principal.class to a TestPrincipalProvider (all exists today),
TestPrincipalProvider calls out to a new singleton object to get the
actual Principal. The individual tests can also get access to that
singleton and configure the result they'd like to be returned.
Singleton needs to be cleared in teardown.

It seems like there *must* be a way to do this on the fly with Guice
but I can't find it yet. I did some digging and found mention of some
introspection capabilities in Guice but nothing I tried seems to work,
and I've yet to locate any examples of anyone doing this.

Thoughts?

Devan

-- 
Devan Goodwin <dgoodwin(a)rm-rf.ca&gt;
http://rm-rf.ca

[Jesus M. Rodriguez]

On Fri, Apr 30, 2010 at 8:01 AM, Devan Goodwin <dgoodwin(a)rm-rf.ca&gt; wrote:
>  I would like to be able to have an individual unit test configure
> the
>  Principal object that Guice will inject into the component I'm
>  testing. Currently this is done in Guice Modules and thus doesn't
>  really allow you to change bindings on a test by test basis that I can
>  find. Anyone know of a way?
>
>  I've got a workable solution but it's not real pretty, bind
>  Principal.class to a TestPrincipalProvider (all exists today),
>  TestPrincipalProvider calls out to a new singleton object to get the
>  actual Principal. The individual tests can also get access to that
>  singleton and configure the result they'd like to be returned.
>  Singleton needs to be cleared in teardown.
>
>  It seems like there *must* be a way to do this on the fly with Guice
>  but I can't find it yet. I did some digging and found mention of some
>  introspection capabilities in Guice but nothing I tried seems to work,
>  and I've yet to locate any examples of anyone doing this.
>
>  Thoughts? 
Is it possible to get access to the injector and replace the bind
with a new implementation of one that is mocked?

Pseudo code below:

   MockPrincipalProvider mpp = mock(PrincipalProvider.class)...
   when(methodfoo).return(MyTestPrincipal);
   Injector inj = ETHER.getInjector();
   inj.bind(Principal.class).toProvider(MockPrincipalProvider.class)

Again I'm talking out my ear here, but wondering if this is possible?
Maybe you already exhausted this route.

jesus

[Dmitri Dolguikh]

On 10-04-30 9:01 AM, Devan Goodwin wrote:
>  I would like to be able to have an individual unit test configure
> the
>  Principal object that Guice will inject into the component I'm
>  testing. Currently this is done in Guice Modules and thus doesn't
>  really allow you to change bindings on a test by test basis that I can
>  find. Anyone know of a way?
>
>  I've got a workable solution but it's not real pretty, bind
>  Principal.class to a TestPrincipalProvider (all exists today),
>  TestPrincipalProvider calls out to a new singleton object to get the
>  actual Principal. The individual tests can also get access to that
>  singleton and configure the result they'd like to be returned.
>  Singleton needs to be cleared in teardown.
>
>  It seems like there *must* be a way to do this on the fly with Guice
>  but I can't find it yet. I did some digging and found mention of some
>  introspection capabilities in Guice but nothing I tried seems to work,
>  and I've yet to locate any examples of anyone doing this.
>
>  Thoughts?
>
>  Devan
>
>      
Not sure what you're trying to test, but some thoughts:

it seems that we sometimes inject Provider<Principal>, instead of the 
actual object. It is probably due to scoping issues, so I would:

  - modify PrincipalProvider constructor so it doesn't get 
HttpServletRequest injected - it's not being used.
  - inject Principal directly.
  - create test version of the class you are trying to test, extended 
with Principal setter (and set Principal directly in your tests).
  - profit?

-d