docker-compose服务编排 && 使用docker-compose部署Redis集群

前言：
如果我们的项目是分布式的微服务而且我们还用了docker容器，那么我们每启动一个实例都需要自己去docker bulid run
这样的操作，如果一个服务器要在100台服务器上部署，麻烦就来了。
docker-compose 就帮我解决了这一个问题。
通过编写 Dockerfile文件跟compose文件就可以实现一键部署

参考官方文档：
https://docs.docker.com/compose/install/

注意：使用docker-compose 需要基础的docker 服务 所以一定要先安装docker服务

docker-compose 安装

sudo curl -L "https://github.com/docker/compose/releases/download/1.26.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

[root@localhost ~]# sudo curl -L "https://github.com/docker/compose/releases/download/1.26.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   638  100   638    0     0    331      0  0:00:01  0:00:01 --:--:--   331
100 11.6M  100 11.6M    0     0   264k      0  0:00:45  0:00:45 --:--:--  534k
#查看安装的版本
[root@localhost home]# docker-compose -version
docker-compose version 1.26.2, build eefe0d31

编排我们的一个服务

这个服务就是官方提供的。
改服务器中使用到了python 跟redis  但是我们不用下载安装到本地机器。docker容器中会安装。 

第一步、准备我们的程序

#创建一个目录
[root@localhost home]# mkdir composetest
#创建一个app.py 里边内容如下：

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)

#再创建一个文件
[root@localhost ~]# mkdir requirements.txt
#里边内容是
flask
redis

第二步、编写Dockerfile 文件

FROM python:3.7-alpine
WORKDIR /code
ENV FLASK_APP app.py
ENV FLASK_RUN_HOST 0.0.0.0
RUN apk add --no-cache gcc musl-dev linux-headers
COPY requirements.txt requirements.txt
RUN pip install -r requirements.txt
EXPOSE 5000
COPY . .
CMD ["flask", "run"]

第三步 编写我们的compose文件

docker-compose.yml

version: '3'
services:
  web:
    build: .
    ports:
      - "5000:5000"
  redis:
    image: "redis:alpine"

第四步，编译运行我们的Compose

#这里发现报了一个错，是因为我们没有启动我们的docker服务，启动我们docker服务就可以了
[root@localhost composetest]# docker-compose up
ERROR: Couldn't connect to Docker daemon at http+docker://localhost - is it running?

If it's at a non-standard location, specify the URL with the DOCKER_HOST environment variable.
#启动我们的docker 服务
[root@localhost composetest]# service docker start
[root@localhost composetest]# docker-compose up
Building web
Step 1/10 : FROM python:3.7-alpine
 ---> ae3ec9b0407e
Step 2/10 : WORKDIR /code
 ---> Using cache
 ---> 70ecbbb37bf5
Step 3/10 : ENV FLASK_APP app.py
 ---> Using cache
 ---> 9ef08ea0e2b7
Step 4/10 : ENV FLASK_RUN_HOST 0.0.0.0
 ---> Using cache
 ---> 967e0c411602
Step 5/10 : RUN apk add --no-cache gcc musl-dev linux-headers
 ---> Running in d4b270d752ee
fetch http://dl-cdn.alpinelinux.org/alpine/v3.12/main/x86_64/APKINDEX.tar.gz
fetch http://dl-cdn.alpinelinux.org/alpine/v3.12/community/x86_64/APKINDEX.tar.gz
(1/13) Installing libgcc (9.3.0-r2)
(2/13) Installing libstdc++ (9.3.0-r2)
(3/13) Installing binutils (2.34-r1)
(4/13) Installing gmp (6.2.0-r0)
(5/13) Installing isl (0.18-r0)
(6/13) Installing libgomp (9.3.0-r2)
...
redis_1  | 1:M 05 Aug 2020 10:53:48.408 * Ready to accept connections
web_1    |  * Serving Flask app "app.py"
web_1    |  * Environment: production
web_1    |    WARNING: This is a development server. Do not use it in a production deployment.
web_1    |    Use a production WSGI server instead.
web_1    |  * Debug mode: off
web_1    |  * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)

启动该浏览器查看

查看我们的镜像

#这里发现了componse给我生跟下载的镜像
[root@localhost ~]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
composetest_web     latest              acb922109420        6 minutes ago       196MB
python              3.7-alpine          ae3ec9b0407e        30 hours ago        41.7MB
redis               alpine              c7b388ce3d39        2 weeks ago         32.1MB

#查看正在运行的容器
[root@localhost ~]# docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES
dc9992b04caf        composetest_web     "flask run"              8 minutes ago       Up 3 minutes        0.0.0.0:5000->5000/tcp   composetest_web_1
70358a6b7dcf        redis:alpine        "docker-entrypoint.s…"   8 minutes ago       Up 3 minutes        6379/tcp                 composetest_redis_1

如果想停止compose 使用 

$ docker-compose down  

重新编辑我们的compose文件然后重新编译

version: '3'
services:
  web:
    build: .
    ports:
      - "5000:5000"
	#增加当前目录（也可以指定目录）挂载目录 到我们的 web容器中
    volumes:
      - .:/code
    environment:
      FLASK_ENV: development
  redis:
    image: "redis:alpine"

#重新编译执行
[root@localhost composetest]# docker-compose up
Starting composetest_redis_1 ... done
Recreating composetest_web_1 ... done
....
web_1    |  * Serving Flask app "app.py"
web_1    |  * Environment: production
web_1    |    WARNING: This is a development server. Do not use it in a production deployment.
web_1    |    Use a production WSGI server instead.
web_1    |  * Debug mode: off
web_1    |  * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)

#进入容器内部查看 有我们的挂载目录
[root@localhost ~]# docker exec -it b7ded709ef70 /bin/bash
OCI runtime exec failed: exec failed: container_linux.go:349: starting container process caused "exec: \"/bin/bash\": stat /bin/bash: no such file or directory": unknown
[root@localhost ~]# docker exec -it b7ded709ef70 /bin/sh
/code # ll
/bin/sh: ll: not found
/code # ls
Dockerfile          __pycache__         app.py              docker-compose.yml  requirements.txt
/code # 

修改程序重新部署

#修改我们app.py return的内容，让我们看出变化就行
#因为我们将目录之间挂载到了容器内部所以 我不用重新编译

按理说修改py文件不需要重新编译就可以生效，但是我这里不行，重新部署以后才生效（docker-compose up）

其他命令

docker-compose up -d

后台启动运行

docker-compose run web env

单独运行某一个 容器 

docker-compose stop

如果你启动的时候用的后台启动，那么停止的时候需要用到这个命令
也可以停止的时候将挂载的卷也停止
docker-compose down --volumes
使用这个命令的时候要在运行 compose的目录下边才可以

docker-compose rm

如果我们想删除不再使用的容器，可以用这个命令

compose中的网络

使用compose 他会自动给我创建一个他的网络

[root@localhost composetest]# docker network ls
NETWORK ID          NAME                  DRIVER              SCOPE
97b350eb250b        bridge                bridge              local
93420c0b315f        composetest_default   bridge              local
6548c36a41d1        host                  host                local
49146853ccd2        none                  null                local
bf4e79dbc031        redis                 bridge              local

app.py里边连接redis 没有配置ip 就是应为这个原因。默认通过容器名称就可以ping通

docker-compose.yml

官方文档地址：
https://docs.docker.com/compose/compose-file/

规则介绍：
1、Dockerfile里边可以使用的命令这里都可以使用
2、docker-compose.yml里边必须包含 两个 version 跟services
     version:这个根据官方来写，这个版本号跟docker容器相关

 services:就是我们需要编排的每一个容器，这个容器可以是我们自己构建的也可以是从远程库下载的。

总结：
docker-compose.yml 编写就需要三层
1、version #指定版本号
2、services #需要的容器
3、其他 比如挂载 网络等等

docker-compose.yml demo

version: "3.8" #版本号
services:    #server标签
	#服务器一
  redis:
    image: redis:alpine
    ports:
      - "6379"
    networks:
      - frontend
    deploy:
      replicas: 2
      update_config:
        parallelism: 2
        delay: 10s
      restart_policy:
        condition: on-failure
#服务器二
  db:
    image: postgres:9.4
    volumes:
      - db-data:/var/lib/postgresql/data
    networks:
      - backend
    deploy:
      placement:
        max_replicas_per_node: 1
        constraints:
          - "node.role==manager"

  vote:
    image: dockersamples/examplevotingapp_vote:before
    ports:
      - "5000:80"
    networks:
      - frontend
    depends_on:
      - redis
    deploy:
      replicas: 2
      update_config:
        parallelism: 2
      restart_policy:
        condition: on-failure

  result:
    image: dockersamples/examplevotingapp_result:before
    ports:
      - "5001:80"
    networks:
      - backend
    depends_on:
      - db
    deploy:
      replicas: 1
      update_config:
        parallelism: 2
        delay: 10s
      restart_policy:
        condition: on-failure

  worker:
    image: dockersamples/examplevotingapp_worker
    networks:
      - frontend
      - backend
    deploy:
      mode: replicated
      replicas: 1
      labels: [APP=VOTING]
      restart_policy:
        condition: on-failure
        delay: 10s
        max_attempts: 3
        window: 120s
      placement:
        constraints:
          - "node.role==manager"

  visualizer:
    image: dockersamples/visualizer:stable
    ports:
      - "8080:8080"
    stop_grace_period: 1m30s
    volumes:
      - "/var/run/docker.sock:/var/run/docker.sock"
    deploy:
      placement:
        constraints:
          - "node.role==manager"
#网络相关配置
networks:
  frontend:
  backend:
#卷相关 就是挂的目录
volumes:
  db-data:

depends_on 这个标签很重要

如果某一个服务器启动依赖其他的服务，可以使用这个标签

version: "3.8"
services:
  web:
    build: .
    depends_on:
      - db
      - redis
  redis:
    image: redis
  db:
    image: postgres

docker-compose使用实例

官网地址：https://docs.docker.com/compose/

 拿到项目的docker-compose.yml执行运行

[root@localhost my_wordpress]# ll
总用量 4
-rw-r--r--. 1 root root 591 8月   5 20:08 docker-compose.yml
[root@localhost my_wordpress]# docker-compose up -d

使用docker-compose 编排redis-cluster集群

如果想单纯使用docker 启动一个redis-cluster集群
点击这里跳转：

准备我们的配置文件

这里我们使用一个批量的脚本生成6个redis实例的配置文件

#创建一个存放我们docker-compose.yml的目录
#我们生成的配置文件也放到这个里边统一管理
[root@localhost home]# mkdir -p /home/redis-compose/
#进入这个目录编写脚本文件
[root@localhost redis-compose]# ll
-rwxr-xr-x. 1 root root  458 8月   6 01:47 redis-cluter.sh

redis-cluter.sh 内容：

for port in $(seq 1 6)
do
mkdir -p /home/redis-compose/node-${port}/conf
mkdir -p /home/redis-compose/node-${port}/data
touch /home/redis-compose/node-${port}/conf/redis.conf
cat << EOF >> /home/redis-compose/node-${port}/conf/redis.conf
port 6379
bind 0.0.0.0
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
#这里的ip地址要注意 跟我docker-compose.yml里边networks要对应
cluster-announce-ip 172.1.1.1${port}
cluster-announce-port 6379
cluster-announce-bus-port 16379
appendonly yes
EOF
done

#文件生成以后的目录结构
#注意node-x 目录里边是有内容的，具体看上边的那个脚本文件
[root@localhost redis-compose]# ll
总用量 8
-rw-r--r--. 1 root root 2624 8月   6 01:39 docker-compose.yml
drwxr-xr-x. 4 root root   30 8月   6 01:47 node-1
drwxr-xr-x. 4 root root   30 8月   6 01:47 node-2
drwxr-xr-x. 4 root root   30 8月   6 01:47 node-3
drwxr-xr-x. 4 root root   30 8月   6 01:47 node-4
drwxr-xr-x. 4 root root   30 8月   6 01:47 node-5
drwxr-xr-x. 4 root root   30 8月   6 01:47 node-6
-rwxr-xr-x. 1 root root  458 8月   6 01:47 redis-cluter.sh
[root@localhost redis-compose]# 

编写docker-compose.yml文件

version: '3'

services:
    redis-c-1:
        image: redis:5.0.9-alpine3.11
        container_name: redis-c-1
        networks:
            app_net:
                ipv4_address: 172.1.1.11
        ports:
            - 6371:6379
            - 16371:16379
        volumes:
            - ./node-1/conf/redis.conf:/etc/redis/redis.conf:rw
            - ./node-1/data:/data:rw
        command:
            redis-server /etc/redis/redis.conf


    redis-c-2:
        image: redis:5.0.9-alpine3.11
        container_name: redis-c-2
        networks:
            app_net:
                ipv4_address: 172.1.1.12
        ports:
            - 6372:6379
            - 16372:16379
        volumes:
            - ./node-2/conf/redis.conf:/etc/redis/redis.conf:rw
            - ./node-2/data:/data:rw
        command:
            redis-server /etc/redis/redis.conf

    redis-c-3:
        image: redis:5.0.9-alpine3.11
        container_name: redis-c-3
        networks:
            app_net:
                ipv4_address: 172.1.1.13
        ports:
            - 6373:6379
            - 16373:16379
        volumes:
            - ./node-3/conf/redis.conf:/etc/redis/redis.conf:rw
            - ./node-3/data:/data:rw
        command:
            redis-server /etc/redis/redis.conf

    redis-c-4:
        image: redis:5.0.9-alpine3.11
        container_name: redis-c-4
        networks:
            app_net:
                ipv4_address: 172.1.1.14
        ports:
            - 6374:6379
            - 16374:16379
        volumes:
            - ./node-4/conf/redis.conf:/etc/redis/redis.conf:rw
            - ./node-4/data:/data:rw
        command:
            redis-server /etc/redis/redis.conf

    redis-c-5:
        image: redis:5.0.9-alpine3.11
        container_name: redis-c-5
        networks:
            app_net:
                ipv4_address: 172.1.1.15
        ports:
            - 6375:6379
            - 16375:16379
        volumes:
            - ./node-5/conf/redis.conf:/etc/redis/redis.conf:rw
            - ./node-5/data:/data:rw
        command:
            redis-server /etc/redis/redis.conf

    redis-c-6:
        image: redis:5.0.9-alpine3.11
        container_name: redis-c-6
        networks:
            app_net:
                ipv4_address: 172.1.1.16
        ports:
            - 6376:6379
            - 16376:16379
        volumes:
            - ./node-6/conf/redis.conf:/etc/redis/redis.conf:rw
            - ./node-6/data:/data:rw
        command:
            redis-server /etc/redis/redis.conf

networks:
  app_net:
    ipam:
      driver: default
      config:
        - subnet: "172.1.1.0/16"
        

#使用 docker-compose 启动我们编排的容器
#注意如果你的compose文件名称不是docker-compose.yml 需要 用 -f 参数去指定你的文件名称
# 如果想后台运行 请加 -d 参数
[root@localhost redis-compose]# docker-compose up
Creating redis-c-5 ... done
Creating redis-c-1 ... done
Creating redis-c-4 ... done
Creating redis-c-2 ... done
Creating redis-c-3 ... done
Creating redis-c-6 ... done
Attaching to redis-c-3, redis-c-4, redis-c-2, redis-c-5, redis-c-1, redis-c-6
redis-c-1    | 1:C 05 Aug 2020 17:49:41.901 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
redis-c-1    | 1:C 05 Aug 2020 17:49:41.901 # Redis version=5.0.9, bits=64, commit=00000000, modified=0, pid=1, just started
redis-c-1    | 1:C 05 Aug 2020 17:49:41.901 # Configuration loaded
redis-c-1    | 1:M 05 Aug 2020 17:49:41.902 * No cluster configuration found, I'm af5824e59700e395bf61bf4f2327de2b8ad001d6
redis-c-1    | 1:M 05 Aug 2020 17:49:41.903 * Running mode=cluster, port=6379.
redis-c-1    | 1:M 05 Aug 2020 17:49:41.903 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.

...

redis-c-6    | 1:S 05 Aug 2020 17:51:14.067 * Background AOF rewrite terminated with success
redis-c-6    | 1:S 05 Aug 2020 17:51:14.067 * Residual parent diff successfully flushed to the rewritten AOF (0.00 MB)
redis-c-6    | 1:S 05 Aug 2020 17:51:14.067 * Background AOF rewrite finished successfully
#这里可以看到启动成功了

查看并进入我们的容器

#查看 我们redis 集群docker 
[root@localhost redis-compose]# docker ps 
CONTAINER ID        IMAGE                    COMMAND                  CREATED             STATUS              PORTS                                              NAMES
af8c19edbf95        redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   17 minutes ago      Up 17 minutes       0.0.0.0:6371->6379/tcp, 0.0.0.0:16371->16379/tcp   redis-c-1
c2ba79b90384        redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   17 minutes ago      Up 17 minutes       0.0.0.0:6376->6379/tcp, 0.0.0.0:16376->16379/tcp   redis-c-6
bcdf96e04d30        redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   17 minutes ago      Up 17 minutes       0.0.0.0:6375->6379/tcp, 0.0.0.0:16375->16379/tcp   redis-c-5
9a70a5daa05b        redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   17 minutes ago      Up 17 minutes       0.0.0.0:6374->6379/tcp, 0.0.0.0:16374->16379/tcp   redis-c-4
dde18aac17c4        redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   17 minutes ago      Up 17 minutes       0.0.0.0:6373->6379/tcp, 0.0.0.0:16373->16379/tcp   redis-c-3
0e2da8dd3778        redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   17 minutes ago      Up 17 minutes       0.0.0.0:6372->6379/tcp, 0.0.0.0:16372->16379/tcp   redis-c-2

#进入docker

[root@localhost redis-compose]# docker exec -it redis-c-1 /bin/sh

# 配置集群

/data # redis-cli --cluster create 172.1.1.11:6379 172.1.1.12:6379 172.1.1.13:6379 172.1.1.14:6379 172.1.1.15:6379 172.1.1.16:637
9 --cluster-replicas 1

#设置成功后查看集群信息
#注意定义要 加-c 参数 连接cluster集群需要

/data # redis-cli -c
127.0.0.1:6379> CLUSTER nodes
fea4e8577d149b6a5cd7f29751a69d533f45f796 172.1.1.13:6379@16379 master - 0 1596649888558 3 connected 10923-16383
7f823ce1a787f4bd1a4c9cd76fc1d7b581e1d9c9 172.1.1.12:6379@16379 master - 0 1596649888048 2 connected 5461-10922
af5824e59700e395bf61bf4f2327de2b8ad001d6 172.1.1.11:6379@16379 myself,master - 0 1596649888000 1 connected 0-5460
bba53ac2cd0046cb8017ea29b0a07060bfe13863 172.1.1.16:6379@16379 slave 7f823ce1a787f4bd1a4c9cd76fc1d7b581e1d9c9 0 1596649889067 6 connected
cff7ec4bec6409760983ba3cff4403a4e596493e 172.1.1.14:6379@16379 slave fea4e8577d149b6a5cd7f29751a69d533f45f796 0 1596649889000 4 connected
d79a17a36e67f3a6a27d291111ee81d7b1f1cfff 172.1.1.15:6379@16379 slave af5824e59700e395bf61bf4f2327de2b8ad001d6 0 1596649888000 5 connected

如果我们想停止我们的redis 集群 使用
docker-compose stop 就可以停止
docker-compose up 就可以启动
不用在每次一个一个启动