使用jib打包docker镜像实战

序

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

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。