Comprehensive Guide to DevOps Automation with Docker, Jenkins, Maven, and SpringBoot

The article introduces DevOps as a set of practices that bridge development and operations, emphasizing automation of software delivery and infrastructure changes.

It outlines the preparation work required on a CentOS 7 host, including installing JDK 1.8, Maven 3.6.1, Git, Docker, GitLab, Docker Registry, and Jenkins.

Project Structure : Create a SpringBoot application using IDEA or Eclipse.

pom.xml Configuration :

<dependencies>
  <!-- Springboot dependencies -->
  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter</artifactId>
  </dependency>
  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
  </dependency>
  <!-- Devtools for hot reload -->
  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-devtools</artifactId>
    <scope>runtime</scope>
    <optional>true</optional>
  </dependency>
  <!-- Configuration processor -->
  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <optional>true</optional>
  </dependency>
  <!-- Test dependencies -->
  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
  </dependency>
</dependencies>
<build>
  <finalName>springboot</finalName>
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <configuration>
        <source>1.8</source>
        <target>1.8</target>
      </configuration>
    </plugin>
    <plugin>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-maven-plugin</artifactId>
      <executions>
        <execution>
          <goals>
            <goal>repackage</goal>
          </goals>
        </execution>
      </executions>
    </plugin>
    <plugin>
      <groupId>com.spotify</groupId>
      <artifactId>docker-maven-plugin</artifactId>
      <version>0.4.12</version>
      <configuration>
        <dockerDirectory>${project.basedir}</dockerDirectory>
        <resources>
          <resource>
            <targetPath>/</targetPath>
            <directory>${project.build.directory}</directory>
            <include>${project.build.finalName}.jar</include>
          </resource>
        </resources>
      </configuration>
    </plugin>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-jar-plugin</artifactId>
      <configuration>
        <archive>
          <manifest>
            <mainClass>com.flong.SpringbootApplication</mainClass>
          </manifest>
        </archive>
      </configuration>
    </plugin>
  </plugins>
</build>

Dockerfile Example (development environment) :

FROM frolvlad/alpine-oraclejdk8:slim
MAINTAINER [email protected]
RUN ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
RUN mkdir -p /home/devsoft/springboot_dev
WORKDIR /home/devsoft/springboot_dev
EXPOSE 7011
ADD ./target/springboot.jar ./
CMD java ${JAVA_OPTS_DEFAULT} -Djava.security.egd=file:/dev/./urandom -jar springboot.jar

Key Docker instructions such as WORKDIR, ADD, and CMD are explained, along with environment variable handling.

build.sh Shell Script (used by Jenkins to build, tag, push, and run images):

#!/usr/bin/env bash
# Dynamic variables must not contain spaces or tabs
IMG_SERVER="$1"
IMG_NAME="$2"
IMG_VERSION="$3"
IMG_PORT="$4"
RUN_EVN="$5"
IMG_PATH="$6"

echo "服务地址：$IMG_SERVER"
echo "工程镜像名称：$IMG_NAME"
echo "工程版本号：$IMG_VERSION"
echo "工程端口：$IMG_PORT"
echo "服务环境：$RUN_EVN"

REGISTRY_URL="192.168.1.235:5000"
IMG_TAR_GZ_PATH="/home/img_tar_gz_path/"

if [ "$IMG_SERVER" != "" ] && [ "$IMG_NAME" != "" ] && [ "$IMG_VERSION" != "" ] && [ "$IMG_PORT" != "" ]; then
  # Clean up old containers and images
  CONTAINER_ID=$(docker ps -a | grep $IMG_NAME | awk '{print $1}')
  IMAGE_ID=$(docker images | grep $IMG_NAME | awk '{print $3}')
  if [[ "$CONTAINER_ID" != "" ]]; then
    docker rm -f $CONTAINER_ID
  fi
  if [[ "$IMAGE_ID" != "" ]]; then
    docker rmi -f $IMAGE_ID
  fi
  # Build image (environment‑specific Dockerfile)
  docker build -t $IMG_NAME:$IMG_VERSION -f $IMG_PATH"env/"Dockerfile_$RUN_EVN $IMG_PATH
  # Tag and push to private registry
  docker tag $IMG_NAME:$IMG_VERSION $REGISTRY_URL/$IMG_NAME:$IMG_VERSION
  docker push $REGISTRY_URL/$IMG_NAME:$IMG_VERSION
  # Save image tarball
  docker save $IMG_NAME -o $IMG_TAR_GZ_PATH/$IMG_NAME.tar.gz
  # Run container
  docker run -d --network default_network --restart=always --env-file=./.env -e spring.profiles.active=$RUN_EVN \
    --expose=$IMG_PORT --name=$IMG_NAME -p $IMG_PORT:$IMG_PORT $IMG_NAME:$IMG_VERSION
else
  echo ".......Illegal Command Operation......."
fi

The script demonstrates conditional checks, cleanup of dangling images, building with environment‑specific Dockerfiles, tagging, pushing to a private registry, saving the image, and running the container.

Docker Commands such as docker save, docker load, docker tag, and docker push are described with examples.

Jenkins Pipeline : The article walks through creating a parameterized Maven job, adding build parameters (server IP, app name, version, port, environment, paths), configuring source code management, setting Maven goals (e.g., clean install -U -Dmaven.test.skip=true), and using SSH Publishers to execute the build.sh script on target machines. Both single‑machine and multi‑machine deployment scenarios are covered, with separate shell scripts for the Jenkins host and remote nodes.

Finally, the article provides a summary, suggestions for further learning, and a list of reference URLs covering Docker documentation, Docker Maven plugin, Fabric8, and related tutorials.