I’ve recently been using the Maven release plugin more and more at work to simplify the process of releasing various Maven artifacts that we produce. I’ll not go into detail about the release plugin as you can read more about it here, but what I will say is that it does a lot of the manual grunt work for you associated with the release of an artifact e.g. checking for unresolved SNAPSHOT dependencies, updating POM versions, committing to your SCM, creating SCM tags etc. There are a few gotchas and quirks to getting it working reliably (hey, this is Maven we’re talking about!) but once it’s working it makes life a little easier.

We use Hudson extensively as our Continuous Integration server to build and test our Maven projects, and we’ve got several jobs configured to allow releases to be performed using the M2 release Hudson plugin. This was all working just fine until we attempted to release something which had unit tests requiring certain properties to be set defining the environment the tests should be executed in. Doing this from the command line involves passing a couple of properties to the surefire plugin using the argLine plugin parameter as discussed here. However, when the tests were executed as part of the release plugin lifecycle, these properties just weren’t being recognised.

Eventually after some Googling (how often is that the case!) we came across a blog post which discussed a little-documented feature of the release plugin that allows arguments to be passed to the surefire plugin using the -Darguments option. And with a bit of careful nesting of single and double quotes were finally able to get the required properties into the surefire plugin as part of the release plugin lifecycle as follows:

-Darguments=”-DargLine=’-Denv=dev -Dsite=london'”