[xwiki-devs] [VOTE] Optional dependencies and Maven

Hi devs, So we now have the concept of optional dependencies at Extension Manager level. This are dependencies that are installed by default (but if they fail they don't fail the whole install) and which can be uninstalled without any impact on what is no longer it's backward dependency. On Maven -> EM side what I did is reuse <optional>true</optional> mostly the following reason: there is no way in pom.xml to put custom stuff in <dependency> so it would be a huge pain to maintain a list of optional dependencies from a property at general pom level. The issue is that the behavior of this <optional> is not exactly the same in EM and Maven: in Maven those dependencies are NOT triggered by default. Still, apart from this it's supposed to be the same meaning and it should not be an issue to install this dependency (if it is then it means you should have used something else like <scope>provided</scope>) but as usually since there is no official way in Maven to say "I just want to use that during the build and it does not make any sens to get this dependency" some projects may have used it that way. So do you think it is OK ? It's not acceptable and we absolutely need to move this kind of information in some general property in the pom <properties> ? -- Thomas Mortagne