Docker basic knowledge notes (5)--DockerCompose

Table of contents

1. Introduction

2. Installation

3. Short answer example

4. Simple rules for YAML files

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1. Introduction

Run the container docker run -d image

Based on the dockerfile file Yunxin docker build -f dockerfile file path -t container name .

If you need to run multiple containers, start them one by one, which is troublesome to operate. Therefore, Docker Compose is introduced to manage multiple container startups. Write the yaml configuration file through docker-compose, and you can start and stop all services with one click through compose. !

Three steps to operate Docker Compose

1. Use a dockerfile to define the required content of the application.

2. Use docker- compose.yml to define the services that make up the application and ensure that they can run together in an isolated environment.

3. Use the docker-compose up command to start and run the entire application.

2. Installation

# 下载
➜  ~ sudo curl -L https://get.daocloud.io/docker/compose/releases/download/1.25.5/dockercompose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose

# 添加运行权限
➜  ~ sudo chmod +x /usr/local/bin/docker-compose

3. Short answer example

1. Application file app.py

import time

import redis
from flask import Flask

app = Flask(__name__)
cache = redis.Redis(host='redis', port=6379)


def get_hit_count():
    retries = 5
    while True:
        try:
            return cache.incr('hits')
        except redis.exceptions.ConnectionError as exc:
            if retries == 0:
                raise exc
            retries -= 1
            time.sleep(0.5)


@app.route('/')
def hello():
    count = get_hit_count()
    return 'Hello World! I have been seen {} times.\n'.format(count)

2.dockerfile file

FROM python:3.6-alpine
ADD . /code
WORKDIR /code
RUN pip install -r requirements.txt
CMD ["flask", "run"]

3.requirements.txt file

flask
redis

4.docker-compose.yaml file

version: '3.3'
services:
  web:
    build: .
    ports:
      - "5000:5000"
    volumes:
      - .:/code
  redis:
    image: "redis:alpine"

5. docker-compose up start 

 Among them, the naming rules for starting services----"folder_service name_num (number of starting services)

6. Check whether there is a configured network

# 查看运行
➜  ~ docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES
5f23dbb8dfc5        composetest_web     "flask run"              23 seconds ago      Up 22 seconds       0.0.0.0:5000->5000/tcp   composetest_web_1
a432fab80dc3        redis:alpine        "docker-entrypoint.s…"   10 minutes ago      Up 22 seconds       6379/tcp                 composetest_redis_1

#查看网络
➜  ~ docker network ls
NETWORK ID          NAME                                 DRIVER              SCOPE
b2de486c0a96        bridge                               bridge              local
5a511e60b5ac        composetest_default                  bridge              local
4b6ca6c1af1f        docker_standalone-fate-130_default   bridge              local
75c6b565c73c        host                                 host                local
9329391ab863        mynet                                bridge              local
0196d25ee724        none                                 null                local

# 内部查看详细
➜  ~ docker network inspect 5a511e60b5ac
[
    {
        "Name": "composetest_default",
        "Id": "5a511e60b5ace3984851007d73b04b2c6be795aea5df74cb09c518f93fe5e557",
        "Created": "2022-04-14T13:36:51.985458301+08:00",
        "Scope": "local",
        "Driver": "bridge",
        "EnableIPv6": false,
        "IPAM": {
            "Driver": "default",
            "Options": null,
            "Config": [
                {
                    "Subnet": "172.19.0.0/16",
                    "Gateway": "172.19.0.1"
                }
            ]
        },
        "Internal": false,
        "Attachable": true,
        "Ingress": false,
        "ConfigFrom": {
            "Network": ""
        },
        "ConfigOnly": false,
        "Containers": {
            "5f23dbb8dfc5ab38883621811b595f2963b35f454f5ba16b442fcd5d94c0e9fc": {
                "Name": "composetest_web_1",
                "EndpointID": "d21e5aab735acc27b456fd878659067519f6453db4d8407e4254abd9dcb47f68",
                "MacAddress": "02:42:ac:13:00:03",
                "IPv4Address": "172.19.0.3/16",
                "IPv6Address": ""
            },
            "a432fab80dc36c3606605aa2e8ea1e30262fc04aec709ce348261fe323c9e479": {
                "Name": "composetest_redis_1",
                "EndpointID": "25372bb5d7eb7280a1a8d6aa697390a2f63da2e03df4f39f1f9063df36e448c2",
                "MacAddress": "02:42:ac:13:00:02",
                "IPv4Address": "172.19.0.2/16",
                "IPv6Address": ""
            }
        },
        "Options": {},
        "Labels": {
            "com.docker.compose.network": "default",
            "com.docker.compose.project": "composetest",
            "com.docker.compose.version": "1.25.5"
        }
    }
]

# ping通
➜  ~ docker exec -it composetest_web_1 ping composetest_redis_1                
PING composetest_redis_1 (172.19.0.2): 56 data bytes
64 bytes from 172.19.0.2: seq=0 ttl=64 time=0.110 ms
64 bytes from 172.19.0.2: seq=1 ttl=64 time=0.079 ms
64 bytes from 172.19.0.2: seq=2 ttl=64 time=0.077 ms
64 bytes from 172.19.0.2: seq=3 ttl=64 time=0.082 ms
^Z64 bytes from 172.19.0.2: seq=4 ttl=64 time=0.080 ms
^C
--- composetest_redis_1 ping statistics ---
5 packets transmitted, 5 packets received, 0% packet loss
round-trip min/avg/max = 0.077/0.085/0.110 ms

4. Simple rules for YAML files

官网： Compose file version 3 reference | Docker Documentation

The core of the main architecture is three layers

# 版本
version: ''

# 服务
services: 
    服务1: web
    # 服务配置
        images
        build
        network
        depends_on
        deploy
        ......
    服务2: redis


# 其他配置 网络/卷、全局规则
volumes:
networks:
configs: