使用spotify的docker-maven-plugin插件將SpringBoot項目打包爲Docker鏡像

此項目的代碼已經放到GitHub中，地址https://github.com/twingao/springboot-docker。先展示SpringBoot項目的目錄結構。

tree springboot-docker/
springboot-docker/
├── pom.xml
└── src
    └── main
        ├── docker
        │   └── Dockerfile
        ├── java
        │   └── com
        │       └── twingao
        │           ├── controller
        │           │   └── DemoController.java
        │           └── SpringbootDockerApplication.java
        └── resources
            └── application.yml

8 directories, 5 files

pom.xml中引入docker-maven-plugin插件。

cat pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.4.RELEASE</version>
        <relativePath/>
    </parent>

    <groupId>com.twingao</groupId>
    <artifactId>springboot-docker</artifactId>
    <version>1.0.0</version>
    <name>springboot-docker</name>
    <description>springboot docker demo</description>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <plugin>
                <groupId>com.spotify</groupId>
                <artifactId>docker-maven-plugin</artifactId>
                <version>0.4.13</version>
                <configuration>
                    <imageName>twingao/${project.name}:${project.version}</imageName>
                    <dockerDirectory>src/main/docker</dockerDirectory>
                    <resources>
                        <resource>
                            <targetPath>/</targetPath>
                            <directory>${project.build.directory}</directory>
                            <include>${project.build.finalName}.jar</include>
                        </resource>
                    </resources>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

在src/main下創建docker目錄，Dockerfile就放在該目錄下。

cat src/main/docker/Dockerfile
FROM openjdk:8-jdk-alpine

VOLUME /opt/tmp

ADD springboot-docker-1.0.0.jar springboot-docker.jar

ENV JAVA_OPTS=""

ENTRYPOINT exec java $JAVA_OPTS -Djava.security.egd=file:/dev/./urandom -jar /springboot-docker.jar

編譯並構建Docker鏡像。

mvn clean package docker:build
[INFO] Scanning for projects...
[INFO]
[INFO] -------------------< com.twingao:springboot-docker >--------------------
[INFO] Building springboot-docker 1.0.0
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- maven-clean-plugin:3.1.0:clean (default-clean) @ springboot-docker ---
[INFO] Deleting /root/code/springboot-docker/target
[INFO]
[INFO] --- maven-resources-plugin:3.1.0:resources (default-resources) @ springboot-docker ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:3.8.1:compile (default-compile) @ springboot-docker ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 2 source files to /root/code/springboot-docker/target/classes
[INFO]
[INFO] --- maven-resources-plugin:3.1.0:testResources (default-testResources) @ springboot-docker ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] skip non existing resourceDirectory /root/code/springboot-docker/src/test/resources
[INFO]
[INFO] --- maven-compiler-plugin:3.8.1:testCompile (default-testCompile) @ springboot-docker ---
[INFO] No sources to compile
[INFO]
[INFO] --- maven-surefire-plugin:2.22.2:test (default-test) @ springboot-docker ---
[INFO] No tests to run.
[INFO]
[INFO] --- maven-jar-plugin:3.1.2:jar (default-jar) @ springboot-docker ---
[INFO] Building jar: /root/code/springboot-docker/target/springboot-docker-1.0.0.jar
[INFO]
[INFO] --- spring-boot-maven-plugin:2.2.4.RELEASE:repackage (repackage) @ springboot-docker ---
[INFO] Replacing main artifact with repackaged archive
[INFO]
[INFO] --- docker-maven-plugin:0.4.13:build (default-cli) @ springboot-docker ---
[INFO] Copying /root/code/springboot-docker/target/springboot-docker-1.0.0.jar -> /root/code/springboot-docker/target/docker/springboot-docker-1.0.0.jar
[INFO] Copying src/main/docker/Dockerfile -> /root/code/springboot-docker/target/docker/Dockerfile
[INFO] Building image twingao/springboot-docker:1.0.0
Step 1/5 : FROM openjdk:8-jdk-alpine

 ---> a3562aa0b991
Step 2/5 : VOLUME /opt/tmp

 ---> Using cache
 ---> ce2415a919e7
Step 3/5 : ADD springboot-docker-1.0.0.jar springboot-docker.jar

 ---> 2717f349a049
Step 4/5 : ENV JAVA_OPTS=""

 ---> Running in e7292f45d4eb
Removing intermediate container e7292f45d4eb
 ---> 5afb54716215
Step 5/5 : ENTRYPOINT exec java $JAVA_OPTS -Djava.security.egd=file:/dev/./urandom -jar /springboot-docker.jar

 ---> Running in e5751ecddf88
Removing intermediate container e5751ecddf88
 ---> 8b3409a5562e
ProgressMessage{id=null, status=null, stream=null, error=null, progress=null, progressDetail=null}
Successfully built 8b3409a5562e
Successfully tagged twingao/springboot-docker:1.0.0
[INFO] Built twingao/springboot-docker:1.0.0
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  36.895 s
[INFO] Finished at: 2020-02-08T15:36:10+08:00
[INFO] ------------------------------------------------------------------------

查看生成的鏡像。

docker images
REPOSITORY                  TAG                 IMAGE ID            CREATED             SIZE
twingao/springboot-docker   1.0.0               8b3409a5562e        48 seconds ago      122MB
openjdk                     8-jdk-alpine        a3562aa0b991        9 months ago        105MB

運行容器，驗證一下。

docker run -d --name springboot-docker -p 8080:8080 twingao/springboot-docker:1.0.0
b6fe11c8726a44b24c90691b48cd6f63c9548eab98161261d38d25102bd387f8

docker ps
CONTAINER ID        IMAGE                             COMMAND                  CREATED             STATUS              PORTS                    NAMES
98cfc8bdbc2d        twingao/springboot-docker:1.0.0   "/bin/sh -c 'exec ja…"   20 seconds ago      Up 18 seconds       0.0.0.0:8080->8080/tcp   springboot-docker

curl http://localhost:8080/demo
Hello World

打開瀏覽器，訪問http://192.168.1.35:8080/demo，也可以訪問。

可以進一步將構建的Docker鏡像push到hub.docker.com上。當然首先應該有一個docker hub賬號。

先修改maven的配置文件,增加docker hub服務配置。

cat /usr/local/maven-3.6.2/conf/settings.xml
...
    <server>
      <id>docker-hub</id>
      <username>docker-hub賬號</username>
      <password>docker-hub密碼</password>
      <configuration>
        <email>docker-hub郵件地址</email>
      </configuration>
    </server>
  </servers>
...

docker-maven-plugin插件增加docker hub配置。

cat pom.xml
...
            <plugin>
                <groupId>com.spotify</groupId>
                <artifactId>docker-maven-plugin</artifactId>
                <version>0.4.13</version>
                <configuration>
                    <imageName>twingao/${project.name}:${project.version}</imageName>
                    <dockerDirectory>src/main/docker</dockerDirectory>
                    <resources>
                        <resource>
                            <targetPath>/</targetPath>
                            <directory>${project.build.directory}</directory>
                            <include>${project.build.finalName}.jar</include>
                        </resource>
                    </resources>
                    <serverId>docker-hub</serverId>
                    <registryUrl>https://index.docker.io/v1/</registryUrl>
                </configuration>
            </plugin>
...

編譯、構建Docker鏡像並push到docker hub中。

mvn clean package docker:build -DpushImage
[INFO] Scanning for projects...
[INFO]
[INFO] -------------------< com.twingao:springboot-docker >--------------------
[INFO] Building springboot-docker 1.0.0
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- maven-clean-plugin:3.1.0:clean (default-clean) @ springboot-docker ---
[INFO] Deleting /root/code/springboot-docker/target
[INFO]
[INFO] --- maven-resources-plugin:3.1.0:resources (default-resources) @ springboot-docker ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:3.8.1:compile (default-compile) @ springboot-docker ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 2 source files to /root/code/springboot-docker/target/classes
[INFO]
[INFO] --- maven-resources-plugin:3.1.0:testResources (default-testResources) @ springboot-docker ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] skip non existing resourceDirectory /root/code/springboot-docker/src/test/resources
[INFO]
[INFO] --- maven-compiler-plugin:3.8.1:testCompile (default-testCompile) @ springboot-docker ---
[INFO] No sources to compile
[INFO]
[INFO] --- maven-surefire-plugin:2.22.2:test (default-test) @ springboot-docker ---
[INFO] No tests to run.
[INFO]
[INFO] --- maven-jar-plugin:3.1.2:jar (default-jar) @ springboot-docker ---
[INFO] Building jar: /root/code/springboot-docker/target/springboot-docker-1.0.0.jar
[INFO]
[INFO] --- spring-boot-maven-plugin:2.2.4.RELEASE:repackage (repackage) @ springboot-docker ---
[INFO] Replacing main artifact with repackaged archive
[INFO]
[INFO] --- docker-maven-plugin:0.4.13:build (default-cli) @ springboot-docker ---
[INFO] Copying /root/code/springboot-docker/target/springboot-docker-1.0.0.jar -> /root/code/springboot-docker/target/docker/springboot-docker-1.0.0.jar
[INFO] Copying src/main/docker/Dockerfile -> /root/code/springboot-docker/target/docker/Dockerfile
[INFO] Building image twingao/springboot-docker:1.0.0
Step 1/5 : FROM openjdk:8-jdk-alpine

 ---> a3562aa0b991
Step 2/5 : VOLUME /opt/tmp

 ---> Using cache
 ---> ce2415a919e7
Step 3/5 : ADD springboot-docker-1.0.0.jar springboot-docker.jar

 ---> 2535eff7e177
Step 4/5 : ENV JAVA_OPTS=""

 ---> Running in 7c7041df4f51
Removing intermediate container 7c7041df4f51
 ---> d87e0602b118
Step 5/5 : ENTRYPOINT exec java $JAVA_OPTS -Djava.security.egd=file:/dev/./urandom -jar /springboot-docker.jar

 ---> Running in 1ea77b69a6cd
Removing intermediate container 1ea77b69a6cd
 ---> 9ccd40c50a80
ProgressMessage{id=null, status=null, stream=null, error=null, progress=null, progressDetail=null}
Successfully built 9ccd40c50a80
Successfully tagged twingao/springboot-docker:1.0.0
[INFO] Built twingao/springboot-docker:1.0.0
[INFO] Pushing twingao/springboot-docker:1.0.0
The push refers to repository [docker.io/twingao/springboot-docker]
fa517bd9ccf3: Pushed
ceaf9e1ebef5: Layer already exists
9b9b7f3d56a0: Layer already exists
f1b5933fe4b5: Layer already exists
1.0.0: digest: sha256:147e1d4475fc74a083bcf50e2a96abd13e8f796fc56b1d5445291fecd7ed8880 size: 1159
null: null
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  52.408 s
[INFO] Finished at: 2020-02-08T21:07:21+08:00
[INFO] ------------------------------------------------------------------------