Re: [m2e-users] Overriding Artifact file resolution during Mojo executio

[Balázs Zsoldos <balazs.zsoldos@xxxxxxxxxx>]

Hi,

I have managed to solve my use-case but it is a bit tricky and it calls internal API. Here is the solution:

  @SuppressWarnings("restriction")

  public static IMavenExecutionContext createExecutionContext(final IMavenProjectFacade facade,

      final IProgressMonitor monitor) throws CoreException {

    return MavenPluginActivator.getDefault().getMavenProjectManagerImpl()

        .createExecutionContext(facade.getPom(), facade.getResolverConfiguration());

  }

  public static <V> V executeInContext(final IMavenProjectFacade facade,

      final Consumer<MavenExecutionRequest> executionRequestModifier,

      final ICallable<V> callable, final IProgressMonitor monitor) throws CoreException {

    IMavenExecutionContext executionContext = createExecutionContext(facade, monitor);

    MavenExecutionRequest executionRequest = executionContext.getExecutionRequest();

    return executionContext.execute((context, monitor1) -> {

      if (executionRequestModifier != null) {

        executionRequestModifier.accept(executionRequest);

      }

      return MavenPlugin.getMaven().createExecutionContext()

          .execute(facade.getMavenProject(monitor), callable, monitor);

    }, monitor);

  }

You can execute an M2E ICallable by calling the function executeInContext. You can modify the state of the executionRequest in the executionRequestModifier parameter (functional interface).

I made the solution by analyzing the source code of M2E a lot (I mean days). I noticed that it can be tricked in the following way:

• I create an executionContext by calling internal API of M2E but I do not call execute on it
• I get the executionRequest from the newly created context
• I call execute on the context and inside the execute, I modify the executionRequest (that I got before calling execute)
• I create an embedded execution context and call execute on it. The embedded context will use the executionRequest of the parent (that is modified).

I have a couple of issues with this solution:

• It uses internal API to create pre-configured execution context that has a non-readonly executionRequest. I do not know how long this will work
• The trick with the embedded executionContext works. However, I got that solution by knowing what is inside the source code. I do not know if this trick will work in the next versions of M2E

I would be really happy if there was a standard and tested API that gives us this functionality. At the moment it is impossible to execute any mojo goal from a plugin with any overridden attribute (e.g.: user properties).

Regards,

Balázs Zsoldos

On Sun, Aug 14, 2016 at 2:44 AM, Balázs Zsoldos <balazs.zsoldos@xxxxxxxxxx> wrote:

Hi,

I would like to have the following steps in my Eclipse plugin:

• Get the dependency tree of a project (done)
• Flatten the dependency tree to a list that can be used to find out build order (done)
• Iterate through the flattened dependency list and call every "mvn package" on each project that is in the Eclipse workspace without tests (done)
• Use the result JAR file of calling "mvn package" for the next project (how?)

When I call execute(MavenProject, MojoExecution, IProgressMonitor) function, how can I override the artifact resolution in the way that I use a JAR file that was the result of a previous build (mvn package).

I checked every function of IMavenExecutionContext interface (and the interfaces it uses) but I could not find a way. Is there a possibility to override the RepositorySystemSession or the WorkspaceReader that belongs to the execution context?

Thanks and regards,

Balázs Zsoldos