Dockerfile构建jar镜像

dockerDockerfilejar包docker-compose

• 一、安装docker和compose
• 二、准备jar包
• 三、编写配置文件
  • 1. Dockerfile
  • 2. docker-compose.yml
  • 3. 查看服务
• 四、补充docker-compose配置

docker的好处自不必多说，启动迅速，占用资源少，方便管理。把jar包build构建成docker镜像，再结合docker-compose管理docker容器的启动，简直是开发Spring cloud项目的最佳助手！

一、安装docker和compose

参考：安装docker 使用CentOS7
参考：安装compose

1.安装稳定版docker compose:
sudo curl -L "https://github.com/docker/compose/releases/download/1.25.0/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
2.文件授权
sudo chmod +x /usr/local/bin/docker-compose
3.查看是否安装成功

$ docker-compose --version
docker-compose version 1.25.0, build 1110ad01

二、准备jar包

自行准备一个可运行的jar包即可，测试使用的是一个eureka注册中心的项目jar包。步骤：
1.创建springboot项目
2.添加eureka依赖

<dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>

3.添加application配置

spring:
  application:
    name: eureka-server

server:
  port: 8761

eureka:
  client:
    registerWithEureka: false
    fetchRegistry: false
  serviceUrl:
    defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/

三、编写配置文件

目录结构

• 测试jar包
• Dockerfile: 构建docker镜像配置
• docker-compose.yml: compose配置,创建docker容器

1. Dockerfile

FROM java:8
MAINTAINER lin
ADD eurake-0.0.1-SNAPSHOT.jar app.jar
EXPOSE 8761
ENTRYPOINT ["java","-jar","app.jar"]

• FROM: 基础镜像,通过jdk8镜像开始
• MAINTAINER: 维护者
• ADD: 复制jar包到镜像内,名字为app.jar
• EXPOSE: 声明端口
• ENTRYPOINT: docker启动时,运行的命令.这里就是容器运行就启动jar服务

进入Dockerfile的同级目录,指定镜像构建:
docker build -t lin/eureka .
最后的点不要漏掉,lin/eureka是给镜像起的名字

查看镜像: docker image ls

REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
lin/eureka          latest              f45c58780812        4 hours ago         691MB
redis               latest              dcf9ec9265e0        3 weeks ago         98.2MB
java                8                   d23bdf5b1b1b        2 years ago         643MB

2. docker-compose.yml

version: '3'
services:
  eureka:
    image: lin/eureka
    container_name: lin-eureka
    restart: always
    ports:
      - 8761:8761

• services: 指定容器服务,下面可配多个服务
• eureka: 服务名字,自己指定.这里就代表我的eureka服务
• image: 指定启动的镜像,就是上边通过Dockerfile构建的镜像
• container_name: 给容器起一个名字
• restart: 可重启,使用always就好
• ports: 声明映射端口

检查配置是否正确
docker-compose config
启动容器服务
docker-compose up
停止并删除容器服务
docker-compose down
强制启动重新建立容器
docker-compose up -d --force-recreate

3. 查看服务

查看进程: docker ps

CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES
f21fdb5bb57c        lin/eureka          "java -jar app.jar"      4 hours ago         Up 4 hours          0.0.0.0:8761->8761/tcp   lin-eureka

查看日志: docker logs lin-eureka

2019-12-16 17:18:17.104  INFO 1 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration' of type [org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.2.2.RELEASE)

2019-12-16 17:18:17.482  INFO 1 --- [           main] com.lyf.eurake.EurakeApplication         : No active profile set, falling back to default profiles: default
2019-12-16 17:18:19.690  WARN 1 --- [           main] o.s.boot.actuate.endpoint.EndpointId     : Endpoint ID 'service-registry' contains invalid characters, please migrate to a valid format.
2019-12-16 17:18:20.315  INFO 1 --- [           main] o.s.cloud.context.scope.GenericScope     : BeanFactory id=6ff43722-b2c2-392e-b72c-6151fa54c3dd
2019-12-16 17:18:21.170  INFO 1 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration' of type [org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2019-12-16 17:18:22.379  INFO 1 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8761 (http)

四、补充docker-compose配置

docker-compose配置,除了使用image指定镜像之外,还可以使用build把构建镜像和启动容器放在一起执行.

version: '3'
services:
  eureka2:
    build: ./eureka
    image: lin-eureka:2
    container_name: lin-eureka-2
    restart: always
    ports:
      - 8762:8761

• build: 指定构建目录,可以使用相对路径
• image: 跟在build后面,指定构建镜像的名字

构建镜像并启动: docker-compose up -d

Creating network "work_default" with the default driver
Building eureka2
Step 1/5 : FROM java:8
 ---> d23bdf5b1b1b
Step 2/5 : MAINTAINER lin
 ---> Using cache
 ---> 79ef5083226e
Step 3/5 : ADD eurake-0.0.1-SNAPSHOT.jar app.jar
 ---> 7efd60a9f862
Step 4/5 : EXPOSE 8761
 ---> Running in 6968db6d10ad
Removing intermediate container 6968db6d10ad
 ---> a01061f73fe1
Step 5/5 : ENTRYPOINT ["java","-jar","app.jar"]
 ---> Running in 00c5dc7031e0
Removing intermediate container 00c5dc7031e0
 ---> 2ed328e41b1c
Successfully built 2ed328e41b1c
Successfully tagged lin-eureka:2

重新构建:
docker-compose build 或者docker-compose up --build

查看镜像: docker image ls

REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
lin-eureka          2                   2ed328e41b1c        49 seconds ago      691MB