Using filesystem as artifact’s repository

What a task I want to solve

We’ve got a library from another company, but we’re only allowed to use it in certain projects ~~for reasons known only to the manager~~. Basically, we don’t even have the option to publish it to the artifact’s repository. Also, some of our projects use Maven; others use Gradle to build.

As a result, we need to have an unified way to store the libraries along with our source code.

Using `libs` folder

The easiest way is to copy the file close to the sources and push it into the Git repository.

Step by step:

copy a library into some folder (usually called libs)

  libs
      |- some-library-123.jar
  ...
  src/main
  ...
  pom.xml

add dependecy into project:

for Maven: specify the dependency with system scope in pom.xml:

  <dependency>
      <groupId>thirdparty</groupId>
      <artifactId>some-library</artifactId>
      <version>123</version>
      <scope>system</scope>
      <systemPath>${basedir}/libs/some-library-123.jar</systemPath>
  </dependency>

for Gradle: use fileTree to specify the dependecy in build.gradle:

  implementation fileTree(dir: 'libs', include: [ 'some-library-123.jar', ...])

So it works, but the `system’ scope is deprecated, and I would like something less verbose and more consistent with other dependencies.

Using Maven folders structure

Maven caches all dependencies in a local repository. The repository has a specific subfolders structure:

.m2/repository
  |- groupId
      |- artifactId
          |- version
              |- .jar file
              |- .pom file
              |- ... some other files like sha1 ...

But nobody said that the folder must always be in $USER_HOME/.m2/repository. We can specify a local repository with a filesystem URL and use the library as a regular dependency, such as:

<repository>  
  <id>libs</id>  
  <url>file://${project.basedir}/libs</url>  
</repository>

Step by step:

create a folder libs

copy the library into folder with command

mvn install:install-file -Dfile=library-name-0.1.jar -DgroupId=com.thirdparty-company-name -DartifactId=library-name -Dversion=0.1 -Dpackaging=jar -DlocalRepositoryPath=libs

specify the repository pointing into the folder

For Maven:

   <repositories>
      <repository>
          <id>local-libs</id>  
          <url>file://${project.basedir}/libs</url>  
      </repository>
      ... 
  </repositories>

For Gradle:

    repositories {
        maven { url "file://$projectDir/libs" }  
    }

add dependecy into project:

for Maven:

  <dependency>
  <groupId>com.thirdparty-company-name</groupId>
  <artifactId>library-name</artifactId>
  <version>0.1</version>
  </dependency>

for Gradle:

  implementation "com.thirdparty-company-name:library-name:0.1"

So, with some extra work in the begining, we’ve got:

cleaner dependency specification;
no coupling between the build script and the filesystem.