Classpath file (/app/jib-classpath-file) doesn't match libs folder if libraries have same artifactId/version

[davinkevin]

Environment:

• Jib version: 3.1+ (3.1.0 and 3.1.1)
• Build tool: maven 3.6.3
• OS: MacOS 10.16

Description of the issue:

In our project, we have two dependencies with the groupId as only difference:

        <dependency>
            <groupId>com.name.app1</groupId>
            <artifactId>rest-client</artifactId>
            <version>2.0.0</version>
        </dependency>
        <dependency>
            <groupId>com.name.app2</groupId>
            <artifactId>rest-client</artifactId>
            <version>2.0.0</version>
        </dependency>

Both are, in this case, in the same version (which never happened before).

If I run the application, I end up with ClassNotFoundException.

If I dig a little in the application, I can see the following results:

> $ docker run -it --entrypoint=/busybox/sh --rm my-custom-image:1.2.3
~ $ ls /app/libs/ | grep rest-client
rest-client-2.0.0-187729.jar
rest-client-2.0.0-54224.jar
~ $ cat /app/jib-classpath-file | sed 's/:/\n/g' | grep rest-client
/app/libs/rest-client-2.0.0.jar
/app/libs/rest-client-2.0.0.jar

To sumarize, jib is working well at lib level to add a suffix at the end of the jar in the /app/libs folder to avoid a filename clash at filesystem level.

But, if we look at the /app/jib-classpath-file to represent the classpath for our app, the hash is not integrated and none of the dependency can be resolved by our app leading to a ClassNotFoundException.

The expected behavoir would be to launch the app with the correct classpath, so to generate correctly the /app/jib-classpath-file.

If you need more information, let me know 😇.

[suztomo]

I want to reproduce the case. Do you know a pair of Maven artifact coordinates (in Maven Central) which has the same artifactId and version?

[chanseokoh]

This is a bug in Jib. We'll work on fixing this, but it seems a bit tricky at the same time.

Workarounds:

1. Downgrade to 3.0 (so that it doesn't use the classpath argument file)
2. Set jib.container.entrypoint yourself in the traditional way with .../libs/*, e.g.,

<container>
  <entrypoint>java,-cp,/app/resources:/app/classes:/app/libs/*,@/app/jib-main-class-file</entrypoint>
</container>

or specifying the main class as well like

<container>
  <entrypoint>java,-cp,/app/resources:/app/classes:/app/libs/*,com.example.YourMainClass</entrypoint>
</container>

BTW, Maven supports another format for a string list:

  <entrypoint>
    <arg>java</arg>
    <arg>-cp</arg>
    <arg>/app/resources:/app/classes:/app/libs/*</arg>
    <arg>@/app/jib-main-class-file</arg>
  </entrypoint>

[davinkevin]

I did downgrade the jib module to 3.0.0. This was the easiest solution while waiting for a fix.

Thank you for your support.

[chanseokoh]

@davinkevin @orevial @pgillet @VixsTy we released Jib build plugins 3.1.2 which should fix this. Try it out.