Mixed pom-first and tycho features reactor vs. Maven Release Plugin

[reckart]

Follow up to #925 and #931.

So, following the advice from the two discussions above, I've been able to set up:

• a "traditional" update site with "features" using Tycho - for this to work, I also had to convert the "feature" modules from pom-first to tycho
• a Maven P2 update site that lives in a Maven repo, also using Tycho (not supporting "features" though)

Now, I'm trying to see how to get this to fly with the Maven Release Plugin. There is a nice description of how to use the Tycho Versions Plugin as part of the Maven Release Plugin builds to synchronize the versions in the OSGi/Eclipse metadata files with the POM versions.

However, I am having a bit of trouble with the setup...

I still have several pom-first modules in my build. These are referenced from a tycho-driven feature module in the feature.xml, e.g.:

   <plugin
         id="org.apache.uima.runtime"
         download-size="0"
         install-size="0"
         version="3.3.0.qualifier"
         unpack="false"/>

Now, when the tycho-versions-plugin scans the reactor for files it needs to update, it updates the p2 update site category.xml file nicely and also touches the feature.xml files, but it fails to update the plugin sections in the feature.xml files since these plugins are pom-first. For one, when applying a release build to a freshly checkout out project, the Eclipse/OSGi metadata files are not generated before the release plugin kicks in.

But even in a repo that was already checked out and built once and has the generated metadata files, the tycho-versions-plugin fails figuring out that these plugin sections belong to pom-first modules from the reactor and that it should update them.

I wonder if there could be some way to allow the tycho-versions-plugin to recognize which pom-first maven modules will be building which bundles so that it knows to update the respective references...

[laeubi]

• a "traditional" update site with "features" using Tycho - for this to work, I also had to convert the "feature" modules from pom-first to tycho

A update site can also contain bundles, no need for a feature at all

Now, I'm trying to see how to get this to fly with the Maven Release Plugin. There is a nice description of how to use the Tycho Versions Plugin as part of the Maven Release Plugin builds to synchronize the versions in the OSGi/Eclipse metadata files with the POM versions.

If yo use the maven-updatesite you don't need any Tycho specific workflow that's what is is made for.

If you want to use the tycho flow it will most probably only work for a pure tycho and not for a mixed setup.

[laeubi]

I don't think this will work well, even though the id might map the BSN this is not a requirement for a pom-first bundle.

[reckart]

Of course it is not a requirement, but it could be a way for pom-first maintainers to shoe-horn knowledge about the pom-first modules into the Tycho build. Another approach could be to add plugin a parameter like this:

<plugin>
  <groupId>org.eclipse.tycho</groupId>
  <artifactId>tycho-versions-plugin</artifactId>
  <configuration>
    <alwaysGeneratePomChangesForArtifacts>
      <artifact>
        <groupId>${project.groupId}</groupId>
        <artifactId>my-pom-first-module</artifactId>
        <bsn>my.pom.first.module</bsn>
      </artifact>
    </alwaysGeneratePomChangesForArtifacts >
  </configuration>
</plugin>

The tycho-versions-plugin should then update all references to the my.pom.first.module with the version of the ${project.groupId}:my-pom-first-module module.

[reckart]

Just to make this clearer again:

<feature
      id="org.apache.uima.runtime.feature"
      label="UIMA Runtime"
      version="3.3.0.qualifier">   
  <!-- This version is updated because this feature.xml lives in a Tycho-managed module -->

   <plugin
         id="org.apache.uima.runtime"
         version="3.3.0.qualifier"/> 
  <!-- 
    This version is not updated because Tycho does not know that org.apache.uima.runtime
    lives in the pom-first reactor module uimaj-ep-runtime. If this knowledge could somehow be provided
    to the tycho-versions-plugin, it could also update this version.
  -->
</feature>

<plugin>
  <groupId>org.eclipse.tycho</groupId>
  <artifactId>tycho-versions-plugin</artifactId>
  <configuration>
    <alwaysGeneratePomChangesForArtifacts>
      <artifact>
        <groupId>${project.groupId}</groupId>
        <artifactId>uimaj-ep-runtime</artifactId>
        <bsn>org.apache.uima.runtime</bsn>
      </artifact>
    </alwaysGeneratePomChangesForArtifacts >
  </configuration>
</plugin>

[laeubi]

I don't know if this is working at all, if you have a version the feature it should be used as is 3.3.0.qualifier is not a valid version here.
If you like it to use the version of the build it has to be 0.0.0 and the tycho build will replace it with the correct build version.

[reckart]

Excellent feedback! 💯

Replacing the version in the plugin declarations of the feature.xml with 0.0.0 works as expected and removes the need of having the tycho-versions-plugin update them at all!

I didn't try it yet, but I suppose the version in the feature element itself should remain x.x.x.qualifier?