added Dockerfile and extended Readme with setup information

Author: danielprinz

Dockerfile

@@ -0,0 +1,46 @@
+# Use slim version without ui related stuff
+FROM gitlab/gitlab-runner:ubuntu-v10.6.0
+
+# Install add-apt-repository - this is needed because gitlab-runner still uses 14.04 and we want to get the latest jdk8 version
+RUN  apt-get update && apt-get install -y software-properties-common python-software-properties
+
+# Install latest Jdk 8
+RUN add-apt-repository ppa:openjdk-r/ppa && \
+  apt-get update && \
+	apt-get install -y openjdk-8-jdk && \
+	apt-get clean && \
+	rm -rf /var/lib/apt/lists/* && \
+	rm -rf /var/cache/oracle-jdk8-installer;
+
+# Fix certificate issues, found as of
+# https://bugs.launchpad.net/ubuntu/+source/ca-certificates-java/+bug/983302
+RUN apt-get update && \
+  apt-get install -y ca-certificates-java && \
+	apt-get clean && \
+	update-ca-certificates -f && \
+	rm -rf /var/lib/apt/lists/* && \
+	rm -rf /var/cache/oracle-jdk8-installer;
+
+# Setup JAVA_HOME, this is useful for docker commandline
+ENV JAVA_HOME /usr/lib/jvm/java-8-openjdk-amd64/
+RUN export JAVA_HOME
+
+# Install Maven 3.5.3
+RUN curl --create-dirs --location --fail --show-error --silent --output /tmp/maven.tar.gz --url http://www-eu.apache.org/dist/maven/maven-3/3.5.3/binaries/apache-maven-3.5.3-bin.tar.gz \
+  && tar -xv -C /tmp -f /tmp/maven.tar.gz \
+  && mv /tmp/apache-maven-3.5.3 /opt/maven \
+  && rm -f /tmp/maven.tar.gz
+ENV M3_HOME=/opt/maven
+ENV PATH=${M3_HOME}/bin:${PATH}
+
+# Export variables so that gitlab-runner user can use them
+ADD --chown=gitlab-runner:gitlab-runner data/.bash_profile /home/gitlab-runner/.bash_profile
+
+# Setup Docker Client
+RUN curl --create-dirs --location --fail --show-error --silent --output /tmp/docker.tgz --url https://download.docker.com/linux/static/stable/x86_64/docker-17.12.0-ce.tgz \
+  && tar -xz -C /tmp -f /tmp/docker.tgz \
+  && mv /tmp/docker/docker /usr/bin \
+  && rm -rf /tmp/docker /tmp/docker
+
+RUN curl --create-dirs --location --fail --show-error --silent --output /usr/bin/docker-compose --url https://github.com/docker/compose/releases/download/1.18.0/docker-compose-Linux-x86_64 \
+  && chmod +x /usr/bin/docker-compose

README.md

@@ -1,2 +1,27 @@
-# java-maven-gitlab-runner
-Gitlab CI Runner Docker image with java & maven installed
+# :palm_tree: java-maven-gitlab-runner
+
+Uses Gitlab CI Runner from https://gitlab.com/gitlab-org/gitlab-runner/blob/master/dockerfiles/ubuntu/Dockerfile and
+extend it with installed:
+* Java 8
+* Maven 3
+* Docker Client
+
+# :wrench: Setup
+## Build
+`docker build -t danielprinz.github.io/java-maven-gitlab-runner .`
+
+## Run
+```
+docker run -d --name my-gitlab-runner --restart always \
+ -v /srv/my-gitlab-runner/config:/etc/gitlab-runner \
+ -v /var/run/docker.sock:/var/run/docker.sock \
+ danielprinz.github.io/java-maven-gitlab-runner:latest
+```
+
+Note: `/srv/my-gitlab-runner/config/config.toml` file contains all gitlab runner specific settings and will be created on registration.
+### Reference
+https://docs.gitlab.com/runner/install/docker.html
+
+### Register Gitlab Runner
+This is needed for the runner to know the Gitlab instance.  
+https://docs.gitlab.com/runner/register/index.html

data/.bash_profile

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+export MAVEN_OPTS="-Xms1024m -Xmx4096m"
+export M3_HOME=/opt/maven
+export PATH=$M3_HOME/bin:$PATH