[xwiki-devs] [Brainstorming] Should we merge the 3 xwiki repos: commons, rendering & platform?

Hi devs, I’d like to start/revisit a brainstorming on the idea of merging the 3 xwiki repos: commons, rendering & platform. Pros: * Nicer to have XWiki Standard be contained in a single repo * More logical since we release the 3 at the same time with the same versions * Simpler to commit. Right now if you make changes that affect more than 1 repo we get failures in the CI + we need several jira issues ideally + developers need to rebuild locally the changes from the other repo or wait for the CI to finish building the changes (takes long). * Simpler for users to report issues. One jira project is simpler to know where to report. * Less CI jobs * Simpler for running tools like jacoco, clover, etc since they can run in a singe maven reactor. * Simpler for releases (e.g. to find the list of committers for the RN, you need to run the command only once instead of 3 times, etc) * Simpler to understand the xwiki code base and for onboarding Cons: * We need to find a solution for Maven plugins that need to be build before they’re used (XAR plugin, Package plugin, etc). One solution for those is to have them in a separate repo and using the last released version for their XWiki dependencies. Unless it now works with Maven to build plugins in the same reactor as where they’re used (need to try it). * Maybe could cause memory issues when running the whole build in a single maven reactor? * Note that I don’t think this would impact the release of commons and rendering modules to Maven Central since we can still configure that in the poms for those modules. * We might need to refactor some of our build checking tools such as the one verifying that commons doesn’t use rendering or platform modules but that’s not a big deal. * Possibly slightly longer paths for building on windows (see below) If we were to agree on the merge, we could keep the separation between the 3 repos with directories and have an addition level such as: xwiki (repo) |_ xwiki-commons |_ xwiki-rendering |_ xwiki-platform Now we could also forge this organization and flatten it with: xwiki (repo) |_ xwiki-(feature) |_ xwiki-(feature)-(subname1) For example: xwiki |_ xwiki-core |_ xwiki-component |_ xwiki-component-api (from commons) |_ xwiki-component-multi (from platform) |_ xwiki-rendering |_ … |_ xwiki-tools We could even try to go with an even flatter structure: xwiki |_ xwiki-component |_ xwiki-component-api (from commons) |_ xwiki-component-multi (from platform) |_ xwiki-rendering |_ … |_ xwiki-tools |_ ... (it would mean that in xwiki-tools, we apply similar rules that for runtime code or override the maven configs) WDYT? Thanks -Vincent