CustoMaven

Minimal private maven repo server written in Java

What is it?

CustoMaven is a web server written with the Spring framework. It lets you serve Maven artifacts from your own self-hosted repository.

How do I use it?

CustoMaven runs on port 80 by default. Set it up either locally or remotely, just make sure it's accessible over http on the port you chose. The port can be changed in application.properties (you have to compile the project yourself if you want to do this).

Either compile the source code or grab the latest release from here.
CustoMaven will set up a folder in /user/CustoMaven/repositories. In here, create a folder with any URL-friendly name. In this example we'll call it my-repo. This will also be the name of your repository. You can create as many repositories as you want.
From your local Maven repository (usually located at /user/.m2/repository), copy the libraries you want to host on your server. Make sure to preserve the folder structure (using json as an example, the folder could be /org/json/json/20160810/json-20160810.*. The full path on the server would be /user/CustoMaven/repositories/my-repo/org/json/json/20160810/json-20160810.*).
Add the repository to your Maven project(s). In our case, the URL would be http://hostname/repos/my-repo

Example implementation in a .pom file:

...
    <repositories>
        <repository>
            <id>CustoMaven repo</id>
            <url>http://hostname/repos/my-repo</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
...

Maven should now be able to pick up your artifacts from your repository.

How does this actually work? / How Maven fetches artifacts

When Maven looks for an artifact in a repository it checks for a file in a certain directory. The directory it looks in is formatted like this: repo-url/{group-id}/{artifact-id}/{version}/{artifact-id}-{version}.jar. If we use the JSON library as an example with our example repo, the full URL would look like this: http://hostname/repos/my-repo/org/json/json/20160810/json-20160810.jar (this is the link to this particular artifact on maven central). This means that if we place the libraries where Maven expects them to be it'll happily download them. Your local maven repository (usually found at /user/.m2/) has the same structure, which is why we can copy the artifacts and their directories from there. This means that we can use any web server of choice to host our files, but where's the fun in that? CustoMaven works by setting up the entire /repositories/-folder as a static resource folder, which lets us put anything in there and Spring will serve the files when you ask for them. Basically, we route http://hostname/repos/ to the /repositories/-folder.

Todo

Make managing repositories and artifacts more user-friendly, preferrably with some sort of user interface. Right now this project is about as (or even less!) useful than a standard web server.