kubernetes-maven-plugin - Dockerfile Build Fails with .git issue

Question

I am testing out some migration in Maven from a Spotify dockerfile plugin with Fabric8 to just using Eclipse's JKube plugin. I have been hitting errors with what I thought would be a simple enough build using a Dockerfile.

The POM config is like so:

            <plugin>
                <groupId>org.eclipse.jkube</groupId>
                <artifactId>kubernetes-maven-plugin</artifactId>
                <version>1.5.1</version>
                <configuration>
                    <images>
                        <image>
                            <name>${docker.image.prefix}/${docker.image.name}</name>
                            <build>
                                <dockerFile>${project.basedir}/Dockerfile</dockerFile>
                            </build>
                        </image>
                    </images>
                </configuration>
            </plugin>

The Dockerfile is (per config above) in the root of the project. It is very simple

FROM adoptopenjdk/openjdk11-openj9:x86_64-ubi-jre-11.0.12_7_openj9-0.27.0
ARG JAR_FILE
ADD target/${JAR_FILE} microservice.jar
ENTRYPOINT ["java", "-jar", "microservice.jar"]

Running mvn clean install k8s:build ends with the following error message:

[INFO] --- kubernetes-maven-plugin:1.5.1:build (default-cli) @ persistence-svc ---
[INFO] k8s: Running in Kubernetes mode
[INFO] k8s: Building Docker image in Kubernetes mode
[ERROR] k8s: Failed to execute the build [Error while trying to build the image:<PROJ>\target\docker\<PREFIX>\<IMAGE>\build\maven\.git\objects\pack\pack-c35818936460f0bb0c1b903466f7bf1a17f22cc8.idx]

I am not sure what I am missing. I tried to add a jKube ignore file but that made no difference.

Any pointers would be much appreciated.

Answer 1

Looks like I was on the correct track with the ignore file. The syntax I had was incorrect. I had just .git/ and needed .git/**.

.git/**
src/**
target/classes/**
target/persistence-svc.jar
target/persistence-svc-sources.jar

It seems a little crazy that this should cause problems. Anyways I am sure there is a nicer solution overall but this gets me going without changing anything other than the plugins.

EDIT:
Indeed there is a better way for my use-case. Use .jkube-dockerinclude instead. Example here.