[jboss-jira] [JBoss JIRA] (WFLY-3197) ExternalContextFactory cuts context from deployment context/requires dependency on module

[Bartosz Baranowski (JIRA)]

    [ https://issues.jboss.org/browse/WFLY-3197?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12963459#comment-12963459 ] 

Bartosz Baranowski commented on WFLY-3197:
------------------------------------------

Ok. I finally got a moment to try it out. 
Well, workaround wont work in 100% cases - I'm actually facing one.
Condition that must be met, is that there are no class versions classhes - for instance SecurityContextFactory and JBossSecurityContext. If there are, Proxy ( created from JNDI Ref ) must run in proper CL, in this case, factory module CL which will isolate it from AS7 env - keep all the factory module classes scoped and isolated. 
Possibly application could create fake module (jboss-deployment-structure->module ) which would contain required classes from deployment and have dependency on factory module to bring all those classes required for lookup. Just before call/lookup application would have to switch TCCL to this fake module. However this is wrong:
 - it moves CL magic into application - this is the original reason I've started to dig ExternalContextFactory.module
 - ( I think ) it will make impossible to translate between classes that have two different versions( one in AS7 space second in factory module ) - for instance security packages suffer from this - iirc static methods - org.jboss.security.SecurityContextFactory.createSecurityContext and SecurityContextAssociation.*
                
> ExternalContextFactory cuts context from deployment context/requires dependency on module
> -----------------------------------------------------------------------------------------
>
>                 Key: WFLY-3197
>                 URL: https://issues.jboss.org/browse/WFLY-3197
>             Project: WildFly
>          Issue Type: Enhancement
>      Security Level: Public(Everyone can see) 
>          Components: Naming
>    Affects Versions: 8.0.0.Final, 8.1.0.CR1
>            Reporter: Bartosz Baranowski
>            Assignee: Bartosz Baranowski
>             Fix For: 8.1.0.Final
>
>
> WFLY-2777 changed CCL for context creation(if module is set in external context factory). This essentially cuts context from deployment classes during creation time. This can cause problems when external-context-factory.module classes (ObjectFactories, etc) require deployment classes to be visible from classloader which created context( external-context.module ) and are not found.
> Steps to reproduce:
> 1. define isolated module IM ( with classloader IM_CL )
> 2. create external-context-factory with module set to IM
> 3. create some deployment with interface, for which proxies should be looked up via external-context ( with classloader D_CL ) - deployment has no dependency on IM, since it may contain legacy classes or unwanted dependencies
> 4. lookup and invoke proxy
> Now what will happen is during deployment external-context will be spawned just fine. However, the runtime outcome wont be pleasing.
> Case 1: application and custom context dont do CCL magic
>  - invocation happen in deployment CCL, hence IM_CL classes are not visible and no classes required for deserialization can be loaded, this will fail ( return javax.naming.Reference instance, since ObjectFactory from IM_CL cant be found )
> Case 2: application or custom context switch CCL to IM_CL for lookup
>  - CCL is set to IM_CL, ObjectFactory can be found, but D_CL classes cant, hence some naming error probably
> Neither of above will work, unless IM_CL and D_CL have some sort of dependency on each other, which just makes module CL configured in external-context-factory irrelevant, since D_CL will require dependency on IM_CL.
> Workaround:
>  yes, store IM_CL in context wrapper and upon first invocation obtain CCL( hopefuly D_CL), create agregating CL and set it as CCL for each context invocation.
> Possible fix:
> 1. pass D_CL and IM_CL as part of env to factory, to allow context/context-wrapper to do some magic
> 2. alter ExternalContextFactory and create agregating/delegating CL, which will just iterate over IM_CL and D_CL if present to load proper classes

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira