Travis CI not using extra Maven repository provided in pom.xml

Question

I have a Java-based GitHub project, fitnessjiffy-spring (I'm currently focused on the "bootstrap" branch). It depends on a library built from another GitHib project, fitnessjiff-etl. I am trying to configure both of these to be built by Travis CI.

Unfortunately, Travis is not as sophisticated as Jenkins or Hudson in dealing with Maven-based Java projects. Jenkins can easily handle dependencies between projects, but the same concept doesn't seem to exist with Travis. If one project depends on another, then that other project must already be built previously... and its artifact uploaded to some Maven repo where the first project can download it later.

My "fitnessjiffy-etl" library is building and deploying just fine. I'm using Bintray for Maven repository hosting, and you can clearly see my artifacts over plain HTTP at:

http://dl.bintray.com/steve-perkins/maven/

In my "fitnessjiffy-spring" project, I am adding this Maven repo location directly in the pom.xml, so that Travis will be able to find that artifact dependency. Here is the state of my POM at the time of this writing. Note the <repositories> element at the bottom of the file.

When I build this project locally, it works just fine. I can see it downloading the Maven artifact from "http://dl.bintray.com/...". However, when I try to build on Travis CI it fails every time. I can see in the console log that Travis is still trying to download the artifact from Maven Central rather than my specified repo.

Does this make sense to anyone else? Why does Maven utilize a custom repository location in a POM file when building locally, but ignores this configuration when running on a Travis CI build?

Answer 1

From digging into this further, I discovered that Travis uses its own proxy for Maven Central, and has configured Maven to force ALL dependency requests through their proxy. In other words, it does not seem possible at this time to use additional Maven repos specified in the POM file of a project built on Travis.

In my case, I ended up refactoring such that project would not need the outside JAR dependency. I also switched to Drone.io, so I could manage my settings on the build server rather than having to carry a YAML file in my repository (which always struck me as a bit daft).

However, even on Drone it's still a major hassle to manage dependencies between multiple projects (extremely common with Java development). For Java, I just don't think there's currently an adequate substitute for Jenkins or Hudson, maybe running on a cheap Digital Ocean droplet or some other VPS provider instance.

Answer 2

In your install phase add a $HOME/.m2/settings.xml define your custom repository.

cache:
  directories:
  - "$HOME/.m2"
install:
- curl -o $HOME/.m2/settings.xml
  https://raw.githubusercontent.com/trajano/trajano/master/src/site/resources/settings.xml
- mvn dependency:go-offline
script:
- mvn clean install site