What is the plan for missing/incompatible lifecycle mappings?

[guw]

I am testing M2E 2.0 and I noticed that a lot of Maven projects don't build. The problem seems to be old lifecycle extensions, which were developed with semantic versioning in mind.

  Cannot satisfy dependency:
    From: Plexus Metadata Generation 0.15.0.201207090126 (org.sonatype.m2e.plexus.annotations 0.15.0.201207090126)
    To: osgi.bundle; org.eclipse.m2e.core [1.0.0,2.0.0)

  Cannot satisfy dependency:
    From: Tycho Project Configurators 0.9.0.201811261502 (org.sonatype.tycho.m2e 0.9.0.201811261502)
    To: osgi.bundle; org.eclipse.m2e.core [1.4.0,2.0.0)

Is there a plan to upgrade all these lifecycle mappings or is there a new repository/catalog to configure?

[laeubi]

In general there are the following options:

1. Ask (or even help) the specific connector project to upgrade to m2eclipse 2.x
2. If the project is abandoned, covers a common plugin (e.g. maven-* or similar widely used) and has a suitable license we can discuss to adopt the connector
3. Check if the connector is actually needed, or if something similar can be archived with a lifecycle-mapping.xml together with incremental build support in the plugin itself.

If I found out correctly your particular case is https://github.com/tesla/m2eclipse-plexus from a first look option 3 seems suitable here, but sadly there is not much description about what this actually offers.

[laeubi]

Is there some doc about lifecycle-mapping.xml?

You can find here how to make a maven-plugin itself compatible with m2eclipse, that way no special connector is required:
https://www.eclipse.org/m2e/documentation/m2e-making-maven-plugins-compat.html

Would it make sense go build a community managed repo of those for Maven plug-ins? I am probably going to run into a few of those and forking and releasing each one individually has a lot of overhead.

Actually m2e-core is somewhat a "community managed repo" and help is welcome here of course! So if you cam along such connector, you can simply suggest that we adopt it, the best would be providing a PR so we can create a CQ for it. This usually takes some time, so its best to start this process early.

[HannesWell]

Option 2 is something I wanted to discuss/suggest as well. I think it would be good if M2E would provide the connectors for the most commonly used/relevant standard Maven Plug-ins, where it is necessary. Mostly from the org.apache.maven group, but if we are eager we could consider mojohouse as well.

Another alternative would be to make maven more cooperative with IDEs by default, as discussed here:
#876

But however it is achieved I think it would be good if the most commonly used standard Maven-plugins work out of the box without the need to install extra plug-ins. The more a plug-in is used the more effort would be justified.

[guw]

I've updated the component and published it here:
https://eclipseguru.github.io/m2eclipse-components/

How does it get added to the discovery catalog?

[laeubi]

I think @fbricon can tell best. As far as I know one can even have custom catalogs, or you can simply install it with Help > Install New Software

[fbricon]

https://github.com/takari/m2e-discovery-catalog/blob/master/org.eclipse.m2e.discovery.oss/src/main/resources-filtered/connectors.xml needs to be updated/curated for m2e 2.x support.

Once done, I can look into publishing a new catalog (will need to change some build stuff)

[guw]

Tycho seems to be affected as well:

  Cannot satisfy dependency:
    From: Tycho Project Configurators 0.9.0.201811261502 (org.sonatype.tycho.m2e 0.9.0.201811261502)
    To: osgi.bundle; org.eclipse.m2e.core [1.4.0,2.0.0)

[laeubi]

Tycho already ships with lifecycle-mapping.xml so there should no connector be required anymore.

[HannesWell]

Tycho already ships with lifecycle-mapping.xml so there should no connector be required anymore.

Although Tycho ships with embedded lifecycle-mappings it can happen that the Tycho connector is suggested because it also provides a mapping for Maven's clean plug-in, but this is somewhat a false positive as explained here:
#917 (comment)

[guw]

Is this depending on the Tycho version?

[cdietrich]

needs 2.7.4+ to my knowledge