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本文主要研究一下如何使用google的jib打包docker镜像
Jib 是谷歌最新开源的 Java 应用的 Docker 镜像生成工具，可以通过 Gradle 或 Maven 直接生成镜像并上传到仓库而不需要 Dockerfile 文件或者其他插件；Jib 支持将资源文件和类分层打包，可以大幅度提升生成镜像的速度
有一些其他的插件也可以通过 Docker 实现生成镜像，如com.palantir.docker等，但是都需要额外配置 Dockerfile, 如果应用仅需要通过 Dockerfile 构建镜像，建议使用 Jib 来提升构建和上传速度
maven
<plugin>
<groupId>com.google.cloud.tools</groupId>
<artifactId>jib-maven-plugin</artifactId>
<version>0.9.9</version>
</plugin>
配置
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<maven.build.timestamp.format>yyyyMMdd</maven.build.timestamp.format>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>com.google.cloud.tools</groupId>
<artifactId>jib-maven-plugin</artifactId>
<version>0.9.9</version>
<configuration>
<container>
<jvmFlags>
<jvmFlag>-Xms512m</jvmFlag>
</jvmFlags>
<ports>
<port>8080</port>
</ports>
<useCurrentTimestamp>true</useCurrentTimestamp>
</container>
<from>
<image>java:8u172-jre-alpine</image>
</from>
<to>
<image>jib-demo:${maven.build.timestamp}</image>
</to>
<allowInsecureRegistries>true</allowInsecureRegistries>
<extraDirectory>${project.basedir}/src/main/jib</extraDirectory>
</configuration>
</plugin>
</plugins>
</build>
这里指定base image为java:8u172-jre-alpine
同时指定生成的image名称为jib-demo:${maven.build.timestamp}
container标签可以指定相关参数，比如jvmFlags指定JVM参数，ports指定expose的端口号
extraDirectory用于指定要添加的目录，默认为${project.basedir}/src/main/jib，即该目录下的文件夹会在docker镜像里头同步创建，目录层级关系以jib下目录层级关系为准。比如该目录下有app/resources/demo.txt，则对应该镜像目录为/app/resources/demo.txt
打包
mvn compile jib:dockerBuild -X
使用jib:dockerBuild是在本地打包镜像，不push到远程，-X参数是显示debug信息
如果使用jib:build命令，则打包之后push到远程
输出日志实例：
[DEBUG] TIMING Building image to Docker daemon [DEBUG] RUNNING Building image to Docker daemon [INFO] Getting base image java:8u172-jre-alpine... [DEBUG] TIMING Pulling base image manifest [DEBUG] RUNNING Pulling base image manifest [DEBUG] TIMING Building application layers [DEBUG] RUNNING Building application layers [INFO] Building dependencies layer... [DEBUG] TIMING Building dependencies layer [DEBUG] RUNNING Building dependencies layer [INFO] Building resources layer... [DEBUG] TIMING Building resources layer [DEBUG] RUNNING Building resources layer [INFO] Building classes layer... [DEBUG] TIMING Building classes layer [DEBUG] RUNNING Building classes layer [INFO] Building extra files layer... [DEBUG] TIMING Building extra files layer [DEBUG] RUNNING Building extra files layer [DEBUG] TIMED Building application layers : 3.498 ms [DEBUG] Building application layers : 3.498 ms [DEBUG] Building extra files layer built sha256:0a9321c621ee2c138d9a93f4ba47f825e20dd7aca0e9206f30bf560122fdaa31 [DEBUG] Building resources layer built sha256:933116c8da4db70000355b750af2f3b5c4545e74db7b5eb0a5e37689ef86d44f [DEBUG] Building classes layer built sha256:a99dbde7d015ba3d15b9265ac38f6536d65b00dd2a864b7003a34742f483939b [DEBUG] TIMED Building extra files layer : 33.718 ms [DEBUG] TIMED Building classes layer : 33.901 ms [DEBUG] Building extra files layer : 33.718 ms [DEBUG] TIMED Building resources layer : 34.062 ms [DEBUG] Building resources layer : 34.062 ms [DEBUG] Building classes layer : 33.901 ms [DEBUG] Building dependencies layer built sha256:a19961ec08095eb70ca3a070945223dcf51500a255a745272276139bf0a29f4e [DEBUG] TIMED Building dependencies layer : 1047.83 ms [DEBUG] Building dependencies layer : 1047.83 ms [INFO] The base image requires auth. Trying again for java:8u172-jre-alpine... //...... [DEBUG] TIMED Pulling base image manifest : 8959.891 ms [DEBUG] Pulling base image manifest : 8959.891 ms [DEBUG] TIMING Setting up base image caching [DEBUG] RUNNING Setting up base image caching [DEBUG] TIMED Setting up base image caching : 0.824 ms [DEBUG] Setting up base image caching : 0.824 ms [DEBUG] TIMING Pulling base image layer sha256:500c0ac4cdc58aee9a008e70466eeec8a4b74b25c29d003764635d2fe1b42827 [DEBUG] RUNNING Pulling base image layer sha256:500c0ac4cdc58aee9a008e70466eeec8a4b74b25c29d003764635d2fe1b42827 [DEBUG] TIMING Pulling base image layer sha256:aa38cd8c77d7320c7489327775e074580db5f23467198aab3e79c7db5cdfbdca [DEBUG] TIMING Pulling base image layer sha256:cb56d62302ec31640b40ca15843e7af6be145966a1064c78ea7afd6f10ce49e6 [DEBUG] RUNNING Pulling base image layer sha256:cb56d62302ec31640b40ca15843e7af6be145966a1064c78ea7afd6f10ce49e6 [DEBUG] TIMING Pulling base image layer sha256:ff3a5c916c92643ff77519ffa742d3ec61b7f591b6b7504599d95a4a41134e28 [DEBUG] RUNNING Pulling base image layer sha256:ff3a5c916c92643ff77519ffa742d3ec61b7f591b6b7504599d95a4a41134e28 [DEBUG] RUNNING Pulling base image layer sha256:aa38cd8c77d7320c7489327775e074580db5f23467198aab3e79c7db5cdfbdca [DEBUG] TIMED Pulling base image layer sha256:500c0ac4cdc58aee9a008e70466eeec8a4b74b25c29d003764635d2fe1b42827 : 612.524 ms [DEBUG] Pulling base image layer sha256:500c0ac4cdc58aee9a008e70466eeec8a4b74b25c29d003764635d2fe1b42827 : 612.524 ms [DEBUG] TIMED Pulling base image layer sha256:ff3a5c916c92643ff77519ffa742d3ec61b7f591b6b7504599d95a4a41134e28 : 9985.702 ms [DEBUG] Pulling base image layer sha256:ff3a5c916c92643ff77519ffa742d3ec61b7f591b6b7504599d95a4a41134e28 : 9985.702 ms [DEBUG] TIMED Pulling base image layer sha256:aa38cd8c77d7320c7489327775e074580db5f23467198aab3e79c7db5cdfbdca : 27267.144 ms [DEBUG] Pulling base image layer sha256:aa38cd8c77d7320c7489327775e074580db5f23467198aab3e79c7db5cdfbdca : 27267.144 ms [DEBUG] TIMED Pulling base image layer sha256:cb56d62302ec31640b40ca15843e7af6be145966a1064c78ea7afd6f10ce49e6 : 54734.971 ms [DEBUG] Pulling base image layer sha256:cb56d62302ec31640b40ca15843e7af6be145966a1064c78ea7afd6f10ce49e6 : 54734.971 ms [DEBUG] TIMING Building container configuration [DEBUG] RUNNING Building container configuration [INFO] Finalizing... [DEBUG] TIMED Building container configuration : 0.462 ms [DEBUG] Building container configuration : 0.462 ms [INFO] Loading to Docker daemon... [DEBUG] TIMED Building image to Docker daemon : 65862.956 ms [DEBUG] Building image to Docker daemon : 65862.956 ms [INFO] [INFO] Container entrypoint set to [java, -Xms512m, -cp, /app/resources/:/app/classes/:/app/libs/*, com.example.JibDemoApplication] [INFO] [INFO] Built image to Docker daemon as jib-demo:20180826 [INFO] [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESS [INFO] ------------------------------------------------------------------------ [INFO] Total time: 01:07 min [INFO] Finished at: 2018-08-26T21:38:11+08:00 [INFO] Final Memory: 26M/493M [INFO] ------------------------------------------------------------------------
查看镜像
docker inspect jib-demo:20180826
[
{
"Id": "sha256:7554492dde84091bc6d015b29ec4bf854bb841b9ec4d8f7bef8b51a8ec59ef94",
"RepoTags": [
"jib-demo:20180826"
],
"RepoDigests": [],
"Parent": "",
"Comment": "",
"Created": "2018-08-26T13:37:05.65Z",
"Container": "",
"ContainerConfig": {
"Hostname": "",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"Tty": false,
"OpenStdin": false,
"StdinOnce": false,
"Env": null,
"Cmd": null,
"Image": "",
"Volumes": null,
"WorkingDir": "",
"Entrypoint": null,
"OnBuild": null,
"Labels": null
},
"DockerVersion": "",
"Author": "",
"Config": {
"Hostname": "",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"ExposedPorts": {
"8080/tcp": {}
},
"Tty": false,
"OpenStdin": false,
"StdinOnce": false,
"Env": [
"PATH=/opt/jdk1.8.0_172/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
"JAVA_HOME=/opt/jdk1.8.0_172"
],
"Cmd": [],
"Image": "",
"Volumes": null,
"WorkingDir": "",
"Entrypoint": [
"java",
"-Xms512m",
"-cp",
"/app/resources/:/app/classes/:/app/libs/*",
"com.example.JibDemoApplication"
],
"OnBuild": null,
"Labels": {}
},
"Architecture": "amd64",
"Os": "linux",
"Size": 186079594,
"VirtualSize": 186079594,
"GraphDriver": {
"Data": null,
"Name": "aufs"
},
"RootFS": {
"Type": "layers",
"Layers": [
"sha256:cd7100a72410606589a54b932cabd804a17f9ae5b42a1882bd56d263e02b6215",
"sha256:317e0b42ef29551507adc792c2dbc389af85c5d68900cf0f08abe907cbd4e199",
"sha256:d6fd5302a9ee64c43b46153e9678153819d6d0e247381acbbe6cbe6ed9de0366",
"sha256:417c6bd0930eb69d17ae5d601898a6a012900ca33c69e612840a3042b2451cbb",
"sha256:8309a5eed5158c5639acb664312ddc7027a2ecb172744f548d6d9fb5f918a744",
"sha256:6ef8c795d7a5e2a07f51d572a90b820e089f89adf30798193f4f3f410a261415",
"sha256:9990447f3d37e3f2dc70718d0ea6602cf7843091d8bbe395f552c9c5dd10551c",
"sha256:ff7910aaeee962d1d86e00742030378a2758da59d8c8cda3fe44314bbddd8081"
]
},
"Metadata": {
"LastTagTime": "0001-01-01T00:00:00Z"
}
}
]
可以看到java -cp指定了/app/libs/、/app/resources/、/app/classes/这三个文件夹
小结
jib默认执行如下操作
COPY libs /app/libs/ COPY resources /app/resources/ COPY classes /app/classes/
也就是将libs拷贝到/app/libs，将resources拷贝到/app/resources，将classes拷贝到/app/classes.
doc
- jib
- Building Docker Image for a Spring Boot App With Jib
- build-containers-faster-with-jib-a-google-image-build-tool-for-java-applications
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。
