Gradle Maven Plugin install/deploy problem sample project

tl;dr

This project illustrates a problem I was having with the Gradle 1.12 Maven Plugin installing extra artifacts (sometimes duplicates, other times incorrect ones) randomly.

The solution, after speaking with Gary Hale at Gradleware was to use the newer Maven Publish Plugin instead. I have included the working solution in the build script.

There seems to be bug in the older Maven Plugin.

Problem description

This project illustrates non-deterministic behavior by the Gradle (v1.12) install task when installing multiple jar and proguard artifacts.

0. Sometimes, executing ./gradlew install --info installs the expected number of artifacts - 4 ('debug' classifier corresponds to jar artifacts; no classifier corresponds to proguard artifacts):

[INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/libs/gradle-example-lower-1.0.0-SNAPSHOT-debug.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT-debug.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/libs/gradle-example-upper-1.0.0-SNAPSHOT-debug.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT-debug.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-upper-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-lower-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT.jar ```

0. Other times, 5 artifacts are installed: 0. This can be because one artifact is installed twice (innocuous):

    <pre>
   

[INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/libs/gradle-example-lower-1.0.0-SNAPSHOT-debug.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT-debug.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-upper-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-upper-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/libs/gradle-example-upper-1.0.0-SNAPSHOT-debug.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT-debug.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-lower-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT.jar

0. Or because one artifact is **incorrectly** installed over the correct one:

    <pre>

[INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/libs/gradle-example-lower-1.0.0-SNAPSHOT-debug.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT-debug.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-lower-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-lower-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/libs/gradle-example-upper-1.0.0-SNAPSHOT-debug.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT-debug.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-upper-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT.jar

0. Finally, I have also seen 6 artifacts installed - in this case, 1 duplicate and 1 overwrite:

[INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-upper-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-upper-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/libs/gradle-example-lower-1.0.0-SNAPSHOT-debug.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT-debug.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-lower-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-lower/1.0.0-SNAPSHOT/gradle-example-lower-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/proguard/gradle-example-lower-1.0.0-SNAPSHOT.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT.jar [INFO] Installing /Users/echen/data/vungle/code/gradle-example/build/libs/gradle-example-upper-1.0.0-SNAPSHOT-debug.jar to /Users/echen/.m2/repository/example/gradle-example-upper/1.0.0-SNAPSHOT/gradle-example-upper-1.0.0-SNAPSHOT-debug.jar

Observations

The problem seems to lie with installing the Proguard artifacts rather than the jar task artifacts (notice that duplication or overwriting install never occurs with the -debug artifacts).

However, if you remove the jar artifacts (comment out jar from [jar, proguard]) from the build.gradle artifacts section, the problem with the duplication and overwriting of Proguard artifacts no longer manifests.

Envrionment

• Gradle 1.12 (with Gradle wrapper)
• Java 1.6.0_65
• Mac OS X 10.9.4