docker-compose 容器内 networks；容器间的 networks 配置

1.容器内的networks ,有一个后管理程序，包括app,postgres,redis；其中app是一个golang后端程序,需要连接到postgres和redis;所以docker-compose.yml是这样的

version: "3.7"
services:
  app:
    build: .
    container_name: "admin-back"
    ports:
      - "10088:10088"
    # links:
    #   - postgres
    #   - redis
    networks:
      - mqtt
      - admin-back

  postgres:
    image: "postgres:alpine"
    networks:
      - admin-back
    environment:
      POSTGRES_DB: "gin-admin"
      POSTGRES_PASSWORD: 123456
    volumes:
      - pgdata:/var/lib/postgresql/data

  redis:
    image: "redis:alpine"
    networks:
      - admin-back
    volumes:
      - rddata:/data

volumes:
  pgdata:
  rddata:
networks:
  mqtt:
    name: mqtt
  admin-back:
    name: admin-back

• 1.三个应用都连接在admin-back,所以应用app可以通过名称postgres,redis连接到数据库
• 2.容器内第二种连接第二种写法 links 也是可以，使用 links时。app可以访问 postgres，redis,但是postgres，redis无法访问app
• 3.其中app还连接到mqtt网络上,mqtt用于下面容器间网络名称

2.1容器间的networks,一个前端项目，使用nginx部署，并且后端接口代理到上面后管理程序的接口,先看yml文件

version: "3.7"
services:
  web:
    image: nginx:alpine
    networks:
      - mqtt
    ports:
      - "8080:8080"
    volumes:
      - ./conf/nginx.conf:/etc/nginx/nginx.conf
      - ./conf/conf.d:/etc/nginx/conf.d
      - D:\work\vue3\ginAdmin-vue3\dist:/usr/share/nginx/html

networks:
  mqtt:
    name: mqtt

• 1.networks连接到mqtt,此时 app和web之间是可以相互ping通的

2.2. 再看nginx 配置

server {
    listen       8080;
    listen  [::]:8080;
    server_name  localhost;
    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
        try_files $uri $uri/ /index.html;
    }

    location /api/ {
        proxy_pass http://app:10088;
    }
}

• 1./api/开头的请求会代理到http://app:10088上面,完成两个容器之间的通讯

3.最后可以看一下mqtt网络的inspect

• 运行 docker network inspect mqtt

[
    {
        "Name": "mqtt",
        "Id": "532560ff2f92af92db2303f4beb06cefbbb1a9bb52e74ea54ed29ac25ecc1e59",
        "Created": "2021-09-20T12:20:22.1251704Z",
        "Scope": "local",
        "Driver": "bridge",
        "EnableIPv6": false,
        "IPAM": {
            "Driver": "default",
            "Options": null,
            "Config": [
                {
                    "Subnet": "172.29.0.0/16",
                    "Gateway": "172.29.0.1"
                }
            ]
        },
        "Internal": false,
        "Attachable": false,
        "Ingress": false,
        "ConfigFrom": {
            "Network": ""
        },
        "ConfigOnly": false,
        "Containers": {
            "3aec5b9e88b524c38c91516dda6a263f434b3b8b5c3adc350dee1c113cdbbcb4": {
                "Name": "nginx_web_1",
                "EndpointID": "091c464b952268ffa017b6a49f0176b640ca18885f42bbef58e74d5173ec9d20",
                "MacAddress": "02:42:ac:1d:00:02",
                "IPv4Address": "172.29.0.2/16",
                "IPv6Address": ""
            },
            "a0a7d81dbaafa7e949e7c64310796f36e3569e01204bd1b547ed3ab862875450": {
                "Name": "admin-back",
                "EndpointID": "0313dfa1bc55074d48fa3177a278f573e87516b7bedcbd7ecfc205b214b304b4",
                "MacAddress": "02:42:ac:1d:00:04",
                "IPv4Address": "172.29.0.4/16",
                "IPv6Address": ""
            }
        },
        "Options": {},
        "Labels": {
            "com.docker.compose.network": "mqtt",
            "com.docker.compose.project": "nginx",
            "com.docker.compose.version": "2.0.0"
        }
    }
]

• 可以看到Containers内部有nginx_web_1和admin-back两个连接到此网络