Dockerize generic Spring boot app with maven plugin

[computerlyrik]

Hi!
I did some testing but cannot achive the following:

A Spring Boot app consists only of a runnable Jar. So the Dockerfile as suggested by Spring itself as follows:

FROM java:8
VOLUME /tmp
ADD gs-spring-boot-docker-0.1.0.jar app.jar
RUN bash -c 'touch /app.jar'
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/app.jar"]

I want to transform this into <build></build> to *get rid of the Dockerfile and make use of the many nice maven properties.

Now, i am still hanging on putting the resulting artifact-0.0.1-SNAPSHOT.jar as app.jar to the docker container.

S/o got any help? How do i configure my assembly?

Yes, i read http://ro14nd.de/docker-maven-plugin/docker-build.html but i do not understand the handling of assemblyDescriptorRef and such.

[rhuss]

Try something like this in the build configuration:

<build>
  <from>${image}</from>
  <assembly>
    <basedir>/</basedir>
    <inline>
      <id>spring-boot-jar</id>
      <dependencySets>
        <dependencySet>
          <useProjectArtifact>true</useProjectArtifact>
          <includes>
            <include>mygroup:app</include>
          </includes>
          <outputDirectory>.</outputDirectory>
          <outputFileNameMapping>app.jar</outputFileNameMapping>
        </dependencySet>
      </dependencySets>
    </inline>
  </assembly>
</build>

Note the outputFileNameMapping config. For assemblies you can everything as described for the maven-assembly-plugin

basedir puts it into / into your image (by default this is /maven).

BTW, soon we will extend direct Dockerfile support with placeholders, also for an assembly so things might get even easier.

[computerlyrik]

@rhuss Thanks a lot for the fast answer.

I am getting the following error:

 Failed to execute goal org.jolokia:docker-maven-plugin:0.13.6:build (build-image) on project myproject: Failed to create assembly for docker image: Error adding file 'de.computerlyrik.mygroup:myproject:jar:0.0.1-SNAPSHOT' to archive: /home/cf/projects/myproject/target/classes isn't a file. with mode dir -> [Help 1]

With the following config

                            <build>
                                <from>java:8</from>
                                <assembly>
                                    <basedir>/</basedir>
                                    <inline>
                                        <id>spring-boot-jar</id>
                                        <dependencySets>
                                            <dependencySet>
                                                <useProjectArtifact>true</useProjectArtifact>
                                                <includes>
                                                    <include>${project.groupId}:${project.artifactId}</include>
                                                </includes>
                                                <outputDirectory>.</outputDirectory>
                                                <outputFileNameMapping>app.jar</outputFileNameMapping>
                                            </dependencySet>
                                        </dependencySets>
                                    </inline>
                                </assembly>
                            </build>

[computerlyrik]

Btw i am running mvn clean package docker:build

[computerlyrik]

Okay. Fail detection complete.

Do NEVER run the docker:build target on compile time :/

Thanks, this above example works!