Docker部署Spring-boot

[toc]

一、基础Spring-boot快速启动

1.1 快速启动

• pom.xml加入如下依赖

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.5.RELEASE</version>
    </parent>

    <properties>
        <java.version>1.8</java.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

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

    <build>
        <finalName>spring-docker</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

• Spring-boot启动类

@SpringBootApplication
public class DockerApplication {

    public static void main(String[] args) {
        SpringApplication.run(DockerApplication.class, args);
    }

}

• 测试API

@RestController
public class DockerStarterApi {

    @GetMapping("/api/docker/hello")
    public String hello() {
        return "hello docker";
    }

}

• 配置启动配置文件application.yml

server:
  port: 9090 # 为了展示效果, 这里改了默认端口8080

• 检查Spring启动

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.0.2.RELEASE)

...

2018-12-17 17:26:13.385  INFO 48740 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
2018-12-17 17:26:13.448  INFO 48740 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 9090 (http) with context path ''
2018-12-17 17:26:13.453  INFO 48740 --- [           main] pers.study.docker.DockerApplication      : Started DockerApplication in 1.982 seconds (JVM running for 2.602)

检查API是否生效

$ curl -XGET 'http://localhost:9090/api/docker/hello'
hello docker

浏览器检查

http://localhost:9090/api/docker/hello

结果检查.png

1.2 打包启动

• 项目打包

完成上面步骤之后，执行打包命令：

$ mvn clean -U -Dmaven.test.skip compile package

因为上面的pom文件里面定义了finalName，所以在这里会看到编译打包之后target目录下会生成spring-docker.jar

<finalName>spring-docker</finalName>

• 测试运行

$ java -jar target/spring-docker.jar

不出意外(有问题留言~)运行结果同上并检查API是否生效即可.

二、Docker快速安装

接下来开始准备Docker

• 安装
  官网下载安装

  检查安装、查看帮助

$ docker --version
Docker version 18.06.0-ce, build 0ffa825

$ docker --help
Usage:  docker [OPTIONS] COMMAND
A self-sufficient runtime for containers
...

• 镜像加速

中国官方镜像加速

三、配置Spring-boot + Docker

• pom.xml 添加docker plugin

    <properties>
        <docker.image.prefix>springboot</docker.image.prefix>
    </properties>

    <build>
        <plugins>
            <!-- Docker maven plugin -->
            <plugin>
                <groupId>com.spotify</groupId>
                <artifactId>docker-maven-plugin</artifactId>
                <version>1.0.0</version>
                <configuration>
                    <imageName>${docker.image.prefix}/${project.build.finalName}</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>

• 创建Dockerfile文件

根据上面pom.xml文件配置<dockerDirectory>src/main/docker</dockerDirectory>，这里配置了docker配置文件的目录，所以需要再src/main下面创建docker文件夹，同时创建Dockerfile文件。
目录机构如图：

docker配置文件结构.png

• 编辑Dockerfile

FROM openjdk:8-jdk-alpine
VOLUME /tmp
ADD spring-docker.jar app.jar
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/app.jar"]

FROM 表示以Java8为基础镜像
VOLUME 表示挂载目录
ADD 拷贝打包文件并重命名为app.jar

ENTRYPOINT 根据下面的官方文档解释大致是为了缩短tomcat启动时间而添加的一个系统属性。

We added a VOLUME pointing to /tmp because that is where a Spring Boot application creates working directories for Tomcat by default. The effect is to create a temporary file on your host under /var/lib/docker and link it to the container under /tmp. This step is optional for the simple app that we wrote here but can be necessary for other Spring Boot applications if they need to actually write in the filesystem.
To reduce Tomcat startup time we added a system property pointing to "/dev/urandom" as a source of entropy. This is not necessary with more recent versions of Spring Boot, if you use the "standard" version of Tomcat (or any other web server).

配置完成！

四、Docker启动Spring-boot

进入module执行：

$ mvn package docker:build

[INFO] Scanning for projects...

...

 ---> Running in e1f8aba72bdf
Removing intermediate container e1f8aba72bdf
 ---> 36a61c09f09a
ProgressMessage{id=null, status=null, stream=null, error=null, progress=null, progressDetail=null}
Successfully built 36a61c09f09a
Successfully tagged springboot/spring-docker:latest
[INFO] Built springboot/spring-docker
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 6.367 s
[INFO] Finished at: 2018-12-17T20:48:21+08:00
[INFO] ------------------------------------------------------------------------

• 查看镜像

$ docker images
REPOSITORY                 TAG                 IMAGE ID            CREATED             SIZE
springboot/spring-docker   latest              36a61c09f09a        2 minutes ago       123MB

• 运行镜像

$ docker run -p 9090:9090 -t springboot/spring-docker
  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.0.2.RELEASE)

2018-12-17 12:53:21.502  INFO 1 --- [           main] pers.study.docker.DockerApplication      : Starting DockerApplication v1.0-SNAPSHOT on 94991c04be5d with PID 1 (/app.jar started by root in /)
2018-12-17 12:53:21.509  INFO 1 --- [           main] pers.study.docker.DockerApplication      : No active profile set, falling back to default profiles: default

···

2018-12-17 12:53:25.255  INFO 1 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
2018-12-17 12:53:25.337  INFO 1 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 9090 (http) with context path ''
2018-12-17 12:53:25.353  INFO 1 --- [           main] pers.study.docker.DockerApplication      : Started DockerApplication in 4.485 seconds (JVM running for 5.346)

• 查看容器

$ docker ps
CONTAINER ID        IMAGE                      COMMAND                  CREATED             STATUS              PORTS                                                                    NAMES
94991c04be5d        springboot/spring-docker   "java -Djava.securit…"   53 seconds ago      Up 52 seconds       0.0.0.0:9090->9090/tcp                                                   quizzical_bhabha

• 验证启动，访问API

$ curl -XGET 'http://localhost:9090/api/docker/hello'
hello docker

至此Docker部署spring-boot搭建完成。

五、移除镜像

• 停止容器

$ docker stop 94991c04be5d
94991c04be5d

• 删除容器

$ docker rm 94991c04be5d
94991c04be5d

• 删除镜像

$ docker image rm springboot/spring-docker
Untagged: springboot/spring-docker:latest
Deleted: sha256:36a61c09f09ab88cfe5a05f564deb57498682f4a6f3ec01d2a8c4fdc80ac1e41
Deleted: sha256:3f9aef70be6d4d43c205454d8874f10bc2f7280f70eb88cd1f04937b7965dd27
Deleted: sha256:9a5800e93615bb4c5128bb36d31ec494327c01f1a9a768c1ff538badf76628b9
Deleted: sha256:d9c66f907448fa9e61fd5f9267d7fcf8e1f4b52d0a20466414f2f45777261284

六、其他配置功能

• 添加环境属性

$ docker run -e "SPRING_PROFILES_ACTIVE=prod" -p 9090:9090 -t springbooot/spring-docker

• 后台启动运行

$ docker run -p 9090:9090 -d springboot/spring-docker

• 开启容器Debug

1. 修改Dockerfile

FROM openjdk:8-jdk-alpine
VOLUME /tmp
ADD spring-docker.jar app.jar
ENV JAVA_OPTS ''
CMD java -Djava.security.egd=file:/dev/./urandom $JAVA_OPTS -jar app.jar

2. docker run

$ docker run -e "JAVA_OPTS=-agentlib:jdwp=transport=dt_socket,address=5005,server=y,suspend=n" -p 9090:9090 -p 5005:5005 -t springboot/spring-docker