This is a sample Spring Boot Application, used to explain the Jenkins pipeline, in creating a full CI/CD flow using docker too.

Jenkins is an open source automation server written in Java. Jenkins helps to automate the non-human part of the software development process, with continuous integration and facilitating technical aspects of continuous delivery. It is a server-based system that runs in servlet containers such as Apache Tomcat.

Docker is a collection of interoperating software-as-a-service and platform-as-a-service offerings that employ operating-system-level virtualization to cultivate development and delivery of software inside standardized software packages called containers. The software that hosts the containers is called Docker Engine.

To run Jenkins jobs that build Docker images, Jenkins itself needs the Docker CLI and access to the host Docker daemon. The cleanest setup is a custom Jenkins image plus a mounted Docker socket.

Use the JenkinsDockerfile in this repository:

docker build -f JenkinsDockerfile -t jenkins-docker .

Run Jenkins with the Docker socket mounted:

docker rm -f vibrant_pare
docker run -d \
  --name jenkins \
  -p 8080:8080 \
  -p 50000:50000 \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -v jenkins_home:/var/jenkins_home \
  jenkins-docker

If the host user cannot run Docker directly, add it to the docker group and log back in:

sudo usermod -aG docker ubuntu

The Sample application built here has the maven jar plugin, so in order to build that as a jar, we just have to do the command:

$ mvn clean install