How do I set up a TeamCity build job to execute a maven job with no pom

Question

We have an in-house developed MOJO that generates content and doesn't require you to have an existing project or POM. Think of the maven archetype plugin, where you can just run mvn [mojo]:[goal] and have maven just execute that goal without a POM.

This MOJO connects to a specific database instance in a specific environment, and generates some metadata for the contents of the database, so our testers can inspect the metadata and locate production-like data that has certain attributes they need for a given test.

When you execute the metadata mojo, maven resolves the MOJO from the available repo's (in our case an Artifactory repo), and it then does its work and returns. It does not create any artifacts or other outputs.

We use TeamCity as our CI server, but it also has metadata generation jobs so with one click a dev can kick of a metadata generation job against a specific database.

The problem with this is the Maven runner in TeamCity requires a POM. If TC hasn't already checked out a project from a VCS, or the project it's checked out doesn't have a POM, the maven runner won't do anything. In this case, there is nothing to check out (the MOJO is resolved from Artifactory) so there is no POM.

I can set up the TC job to use the Command Line runner and have it execute, say, mvn com.example:metadata-generate -DenvironmentName=UAT1, but then it's impossible to specify the maven settings file that maven should use.

So my question is, how do I do this? Is it possible to have the maven runner execute an arbitrary maven command without needing a POM? Alternatively, using the Command line runner, is it possible to have a TC job copy a specific maven settings file to the build agent so it can be referenced in the maven command as mvn com.example:metadata-generate -DenvironmentName=UAT1 -s {path-to-settings-file}?

Answer 1

So its turns out that TC handles pom-less maven builds just fine. My problem was that the MOJO was not declared to not require a project.

Comparing my MOJO with the MavenArchetypePlugin source, I needed to declare my MOJO with the class level javadoc tag @requiresProject false.

Once I had that in place, TC ran my pom-less job perfectly well. All I had to do was clear the Path to POM file: field in the TC build configuration and leave it blank.

Answer 2

You can customize the name of the pom file that you use as an argument into the maven build-step in the teamcity and use this as the second "build step".Lets call the parameter as pom.file.name

In the first step , resolve all the in-house dependencies that you have and set the name of the pom file you want to execute into the variable pom.file.name

If you want to know more about how to change tha value of a variable in teamcity, you can read about it here