spring-boot 和 docker 集成

时间:2022-01-11 16:26:13

描述

java 的 Spring是一个很火的框架,Spring boot 这个也不用说了,Docker 近年也很火热, 本文就介绍下我在 Spring boot + Docker的集成一些经验 :) 其实官网已经有一个手册介绍了 这里

可能会用到的东西

  • JDK 1.8 或者更高
  • Maven 3.0+ 或者是 Gradle 2.3+
  • 一个IDE或者一个记事本
  • 一个本地或者远程的Docker服务
  • 充满好奇心的你

对没错,你至少需要一个Docker,可以安装在本地也可以安装在服务器上,具体安装方式请移步 这里

整个Spring boot的项目

我这边用的是IDEA 创建的

spring-boot 和 docker 集成

➜  sping-boot-docker  tree
.
├── mvnw
├── mvnw.cmd
├── pom.xml
├── sping-boot-docker.iml
└── src
├── main
│ ├── java
│ │ └── org
│ │ └── beyondblog
│ │ ├── DemoApplication.java
│ │ ├── controller
│ │ │ └── HelloController.java
│ │ └── model
│ │ └── Hello.java
│ └── resources
│ ├── application-dev.yml
│ └── application.yml
└── test
└── java
└── org
└── beyondblog
└── DemoApplicationTests.java 12 directories, 10 files

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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion> <groupId>org.beyondblog</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging> <name>demo</name>
<description>Demo project for Spring Boot</description> <parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.3.2.BUILD-SNAPSHOT</version>
<relativePath/> <!-- lookup parent from repository -->
</parent> <properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java.version>1.8</java.version>
</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>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build> <repositories>
<repository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories> </project>

程序很简单创建了一个Controller,然后映射了一个/hello的路由 运行之后如下

➜  target  java -jar demo-0.0.1-SNAPSHOT.jar
➜ sping-boot-docker http "http://127.0.0.1:8080/hello"
HTTP/1.1 200 OK
Content-Type: application/json;charset=UTF-8
Date: Sun, 20 Dec 2015 23:41:14 GMT
Server: Apache-Coyote/1.1
Transfer-Encoding: chunked {
"code": 200,
"messge": "Hello spring! profile=production"
}

可以正常允许,然后配置下pom集成docker (也可以用Dockerfile)

<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>0.3.8</version>
<executions>
<execution>
<phase>deploy</phase>
<goals>
<goal>build</goal>
<goal>tag</goal>
</goals>
</execution>
</executions>
<configuration>
<dockerHost>http://172.16.0.17:2375</dockerHost>
<imageName>registry.****.com/demo:${project.artifactId}</imageName>
<baseImage>docker.io/java:latest</baseImage>
<registryUrl>https://registry.****.com</registryUrl>
<env>
<TZ>'Asia/Shanghai'</TZ>
<LC_ALL>en_US.UTF-8</LC_ALL>
</env>
<resources>
<resource>
<targetPath>/</targetPath>
<directory>${project.build.directory}</directory>
<include>${project.build.finalName}.jar</include>
</resource>
<!--<resource>-->
<!--<targetPath>/web</targetPath>-->
<!--<directory>${project.build.directory}/web</directory>-->
<!--</resource>-->
</resources>
<exposes>
<expose>8080</expose>
</exposes>
<cmd>["java", "-jar", "/${project.build.finalName}.jar"]</cmd>
<image>registry.****.com/demo:${project.artifactId}</image>
<newName>registry.****.com/demo</newName>
<forceTags>true</forceTags>
<pushImage>false</pushImage>
</configuration>
</plugin>
</plugins>
</build>

描述下这段的意思

这儿用到的是spotify公司(就是那个做音乐的)的 docker-maven-plugin 插件用的是目前最新的0.3.8 之前的几个版本有一些目录拷贝的bug。

configuration 节点

有个dockerHost 就是docker服务器的地址 (必选)

imageName 就是生成的镜像名称的东西

baseImage 就是容器基于那个镜像跑 这儿用的是官方的 docker.io/java:latest(可以直接 docker pull 下来,也可以用自己做的。官方的是OpenJDK Java 7 JRE 可以去看它的项目主页 这里 ) 就是一个JRE的环境

registryUrl 这个就是docker自建的私服地址 (可空) 这个填了之后可以触发push 到仓库的指令

env 不解释 默认的时区啊 字符集啊别忘记了 (自制镜像的可以忽略它)

resources 里面包含需要将那些东西包装到镜像里面去,注意我注释的这段

<resource>
<targetPath>/web</targetPath>
<directory>${project.build.directory}/web</directory>
</resource>

这个是为了举例如何包含整个目录(通过看源代码发现 不写include就是copy整个目录 目前插件的0.38版本是,之前的版本好像拷贝目录下的所有文件囧。。。)

exposes 是暴露出容器的那个端口出来,这儿填的是8080 Spring boot 默认就这端口

cmd 是镜像在run的时候默认执行的命令,这儿默认直接run (ps:这块可以指定profile 做生产环境和开发环境的切换)

image 同imageName

newName 是Tag的时候生成的名字 (可选) 强烈推荐加这个 这样默认会把新的容器的tag 设置成latest

forceTags 是否强制tag (强行哟)

pushImage 是否自动push到仓库

基本上需要用的就这么多,当然还有一些其他的参数可以去它的项目主页看

配置完了之后可以用 mvn的一些指令了 如下

docker:build 应该是编译镜像(强烈建议跟 mvn install 不然会有一个坑)

-DpushImage 加这个参数可以强制push镜像到仓库

DOCKER_HOST 加这个环境变量可以设置默认的docker主机地址 不过上面dockerHost已经填了

docker:removeImage 删除镜像吧

-DimageName=xxx 设置镜像名称

docker:tag 打tag

还有一些设置认证的介绍可以去看它的项目主页或者读源代码

下面就执行下

    mvn install docker:build docker:tag

可以看到类似下面的输出

[INFO] Copying /Users/xxx/Documents/code/github/sping-boot-docker/target/demo-0.0.1-SNAPSHOT.jar -> /Users/xxx/Documents/code/github/sping-boot-docker/target/docker/demo-0.0.1-SNAPSHOT.jar
[INFO] Building image registry.****.com/demo:demo
Step 0 : FROM docker.io/java:latest
---> e9de8c6faf15
Step 1 : ENV LC_ALL en_US.UTF-8
---> Using cache
---> 8600ba9f5363
Step 2 : ENV TZ 'Asia/Shanghai'
---> Using cache
---> 9416efd6b55a
Step 3 : ADD /demo-0.0.1-SNAPSHOT.jar //
---> 8cf7cbbd260e
Removing intermediate container 9a53dfb28f52
Step 4 : EXPOSE 8080
---> Running in 4f640acaf303
---> 3a4400f72be5
Removing intermediate container 4f640acaf303
Step 5 : CMD java -jar /demo-0.0.1-SNAPSHOT.jar
---> Running in e8ff98f7e9ce
---> 6834dbb25c33
Removing intermediate container e8ff98f7e9ce
Successfully built 6834dbb25c33
[INFO] Built registry.****.com/demo:demo

通过这个输出可以知道这个插件的原理大致是 install成功jar之后根据pom文件的配置去生成一个dockerfile的文件然后把jar包和dockerfile打包调用docker的api去build去push

可以看到它生成的dockerfile来验证

➜  sping-boot-docker  cd target/docker
➜ docker ls
Dockerfile demo-0.0.1-SNAPSHOT.jar
➜ docker cat Dockerfile
FROM docker.io/java:latest
ENV LC_ALL en_US.UTF-8
ENV TZ 'Asia/Shanghai'
ADD /demo-0.0.1-SNAPSHOT.jar //
EXPOSE 8080
CMD ["java", "-jar", "/demo-0.0.1-SNAPSHOT.jar"]
➜ docker

这个时候去docker服务器上看看镜像的情况

[root@172-16-0-17 cache]# docker images | grep "demo"
registry.****.com/demo demo 6834dbb25c33 5 minutes ago 655.3 MB
registry.****.com/demo latest 6834dbb25c33 5 minutes ago 655.3 MB

可以看到有两个但是通过看它的 digest 其实是同一个镜像不同的名字而已。 因为我们有docker:tag 这样就会在生成一个latest

可以看到镜像还挺大的这主要是那个java的基础镜像大(可以自制一个小的)不过docker每次都是有cache和增量更新所以速度还是很快的

然后验证下能不能正常工作 

docker run -p 6666:8080 registry.****.com/demo

  .   ____          _            __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.3.2.BUILD-SNAPSHOT) 2015-12-21 08:30:05.303 INFO 1 --- [ main] org.beyondblog.DemoApplication : Starting DemoApplication v0.0.1-SNAPSHOT on a734ef04ef23 with PID 1 (/demo-0.0.1-SNAPSHOT.jar started by root in /)
2015-12-21 08:30:05.307 INFO 1 --- [ main] org.beyondblog.DemoApplication : No active profile set, falling back to default profiles: default
2015-12-21 08:30:05.463 INFO 1 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@429e6a3d: startup date [Mon Dec 21 08:30:05 CST 2015]; root of context hierarchy
2015-12-21 08:30:06.471 INFO 1 --- [ main] o.s.b.f.s.DefaultListableBeanFactory : Overriding bean definition for bean 'beanNameViewResolver' with a different definition: replacing [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration.class]] with [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter.class]]
2015-12-21 08:30:07.725 INFO 1 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2015-12-21 08:30:07.745 INFO 1 --- [ main] o.apache.catalina.core.StandardService : Starting service Tomcat
2015-12-21 08:30:07.746 INFO 1 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.0.30
2015-12-21 08:30:07.834 INFO 1 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2015-12-21 08:30:07.835 INFO 1 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 2386 ms
2015-12-21 08:30:08.106 INFO 1 --- [ost-startStop-1] o.s.b.c.e.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2015-12-21 08:30:08.110 INFO 1 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2015-12-21 08:30:08.110 INFO 1 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2015-12-21 08:30:08.110 INFO 1 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2015-12-21 08:30:08.111 INFO 1 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2015-12-21 08:30:08.523 INFO 1 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@429e6a3d: startup date [Mon Dec 21 08:30:05 CST 2015]; root of context hierarchy
2015-12-21 08:30:08.566 INFO 1 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/hello],methods=[GET]}" onto public java.lang.Object org.beyondblog.controller.HelloController.hello()
2015-12-21 08:30:08.568 INFO 1 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2015-12-21 08:30:08.568 INFO 1 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2015-12-21 08:30:08.587 INFO 1 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2015-12-21 08:30:08.587 INFO 1 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2015-12-21 08:30:08.613 INFO 1 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2015-12-21 08:30:08.714 INFO 1 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2015-12-21 08:30:08.782 INFO 1 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2015-12-21 08:30:08.794 INFO 1 --- [ main] org.beyondblog.DemoApplication : Started DemoApplication in 5.045 seconds (JVM running for 7.068)
这个命令 有个 -p 是容器的端口和主机的端口映射 也就是通过6666访问容器的8080端口 可以在加个-d 使它能在后台跑(不过哪有就看不到输出)

先看看数据能不能出来

➜  docker  http "http://172.16.0.17:6666/hello"
HTTP/1.1 200 OK
Content-Type: application/json;charset=UTF-8
Date: Mon, 21 Dec 2015 00:32:20 GMT
Server: Apache-Coyote/1.1
Transfer-Encoding: chunked {
"code": 200,
"messge": "Hello spring! profile=production"
}

好了大致是ok。先这样工头喊我去搬砖了下次在介绍如果处理日志和k8s集群管理


参考文章:

[0] https://spring.io/guides/gs/spring-boot-docker/

[1] https://github.com/spotify/docker-maven-plugin