This document is a proposed new maven plugin for working with maven and git projects.
Initial usage
mkdir src cd src mvn git-checkout https://git-wip-us.apache.org/repos/asf/maven/maven-jar-plugin.git
Given this git-checkout pom configuration:
<checkoutSources> <checkoutSource>org.apache.maven*</checkoutSource> <checkoutSource>org.codehaus.plexus*</checkoutSource> <checkoutSources>
Would produce:
src/maven-jar-plugin-all src/maven-jar-plugin (trunk) src/maven-archiver (checked out at tag of effective dependency version) src/plexus-archiver (checked out at tag of effective dependency version) src/plexus-interpolation (dependency of maven-archiver) src/plexus-utils (checked out at tag of effective dependency version) src/maven-plugin-testing-harness (checked out at tag of effective dependency version)
The pom.xml in maven-jar-plugin-all basically includes all the modules:
<modules>
<module>../maven-jar-plugin</module>
<module>../maven-archiver</module>
<module>../plexus-archiver</module>
<module>../plexus-interpolation</module>
<module>../plexus-utils</module>
<module>../maven-plugin-testing-harness</module>
</modules>
In your IDE you can now open the pom.xml in "maven-jar-plugin-all".
Snapshotting a dependency
Inside the maven-jar-plugin directory you type:
mvn git-snapshot maven-archiver
The plugin checks out master of maven-archiver, modifies the referenced version in maven-jar-plugin/pom.xml
Snapshotting a transitive dependency
Inside the maven-jar-plugin directory you type:
mvn git-snapshot maven-plexus-interpolation
The plugin says:
"plexus interpolation is a dependency of maven-archiver". Choose strategy: 1) Checkout maven-archiver as snapshot too and do transitive dependency upgrade 2) Add overriden dependency in maven-jar-plugin/pom.xml, keep maven-archiver at current version.
Adding another top-level project
At this point you may want to checkout another top-level project:
mvn git-checkout https://git-wip-us.apache.org/repos/asf/maven/maven-surefire-plugin.git
Your "src" folder now looks like this:
src/maven-jar-plugin-all src/maven-jar-plugin src/maven-surefire-plugin-all src/maven-surefire-plugin src/maven-archiver src/plexus-archiver src/plexus-interpolation src/plexus-utils src/maven-plugin-testing-harness
At this point "plexus-utils" is shared by both "maven-surefire-plugin-all" and "maven-jar-plugin-all".
As surefire is checked out, it will attempt to check out the appropriate version of plexus-utils.
At this stage, several interesting things may happen:
1. Plexus-utils is unmodified (we did not do any changes throuh maven-jar-plugin-all) -> correct version is checked out
2. Plexus-utils has modifications at current checkout -> "git-checkout" downloads the remaining repository sources,
creates maven-surefire-plugin-all/pom.xml and then resets any modified repositories to their pre-git-checkout state (effectively this aborts the "git-checkout" and leaves all the repos unchanged.)
Creating a jira/patch for all your changes
TBD
git-submodules ... ?
Github support
The plugin should pick up the $GITHUB environment variable or similar. When resolving a repository, it will check if there is an appropriate fork of the project on the given github account. If such a fork exists it will be cloned as origin and the authorative repository will be added as for instance "apache" (based on hostname of origin, probably). In such a case, the project can always be pushed to origin, since that represents the github fork.
TBD