基于这篇博客文章https://8thlight.com/blog/dariusz-pasciak/2016/10/17/docker-compose-wait-for-dependencies.html

我配置了docker-compose。Yml如下所示:

version: "3.1"

services:
  rabbitmq:
    image: rabbitmq:3.7.2-management-alpine
    restart: always
    environment:
      RABBITMQ_HIPE_COMPILE: 1
      RABBITMQ_MANAGEMENT: 1
      RABBITMQ_VM_MEMORY_HIGH_WATERMARK: 0.2
      RABBITMQ_DEFAULT_USER: "rabbitmq"
      RABBITMQ_DEFAULT_PASS: "rabbitmq"
    ports:
      - "15672:15672"
      - "5672:5672"
    volumes:
      - data:/var/lib/rabbitmq:rw

  start_dependencies:
    image: alpine:latest
    links:
      - rabbitmq
    command: >
      /bin/sh -c "
        echo Waiting for rabbitmq service start...;
        while ! nc -z rabbitmq 5672;
        do
          sleep 1;
        done;
        echo Connected!;
      "

volumes:
  data: {}

然后执行for run =>:

Docker-compose start_dependencies

Rabbitmq服务将以daemon模式启动，start_dependencies将完成工作。

您还可以通过设置一个端点来解决这个问题，该端点使用netcat(使用docker-wait脚本)等待服务启动。我喜欢这种方法，因为在docker-compose中仍然有一个干净的命令部分。Yml，你不需要添加docker特定的代码到你的应用程序:

version: '2'
services:
  db:
    image: postgres
  django:
    build: .
    command: python manage.py runserver 0.0.0.0:8000
    entrypoint: ./docker-entrypoint.sh db 5432
    volumes:
      - .:/code
    ports:
      - "8000:8000"
    depends_on:
      - db

然后docker-entrypoint.sh:

#!/bin/sh

postgres_host=$1
postgres_port=$2
shift 2
cmd="$@"

# wait for the postgres docker to be running
while ! nc $postgres_host $postgres_port; do
  >&2 echo "Postgres is unavailable - sleeping"
  sleep 1
done

>&2 echo "Postgres is up - executing command"

# run the command
exec $cmd

这在官方docker文档中有记载。

PS:你应该在docker实例中安装netcat，如果这是不可用的。要做到这一点，请在Docker文件中添加以下内容:

RUN apt-get update && apt-get install netcat-openbsd -y 

容器开始订购使用

depends_on:

等待前一个容器启动使用脚本

entrypoint: ./wait-for-it.sh db:5432

这篇文章将帮助你 https://docs.docker.com/compose/startup-order/

尝试了许多不同的方法，但喜欢这个简单的:https://github.com/ufoscout/docker-compose-wait

你可以在docker compose文件中使用ENV变量来提交一个服务主机列表(带端口)，应该像这样“等待”:WAIT_HOSTS: postgres:5432, mysql:3306, mongo:27017。

假设你有下面的docker-compose。yml文件(从repo README复制/过去):

version: "3"

services:

  mongo:
    image: mongo:3.4
    hostname: mongo
    ports:
      - "27017:27017"

  postgres:
    image: "postgres:9.4"
    hostname: postgres
    ports:
      - "5432:5432"

  mysql:
    image: "mysql:5.7"
    hostname: mysql
    ports:
      - "3306:3306"

  mySuperApp:
    image: "mySuperApp:latest"
    hostname: mySuperApp
    environment:
      WAIT_HOSTS: postgres:5432, mysql:3306, mongo:27017

接下来，为了让服务等待，你需要在你的Dockerfile中添加以下两行(在服务的Dockerfile中，它应该等待其他服务启动):

ADD https://github.com/ufoscout/docker-compose-wait/releases/download/2.5.0/wait /wait
RUN chmod +x /wait

Dockerfile的完整示例(同样来自项目repo README):

FROM alpine

## Add your application to the docker image
ADD MySuperApp.sh /MySuperApp.sh

## Add the wait script to the image
ADD https://github.com/ufoscout/docker-compose-wait/releases/download/2.5.0/wait /wait
RUN chmod +x /wait

## Launch the wait tool and then your application
CMD /wait && /MySuperApp.sh

有关可能使用的其他详细信息，请参阅README

不建议用于严重的部署，但这里实际上是一个“等待x秒”命令。

在docker-compose 3.4版中，healthcheck添加了一条start_period指令。这意味着我们可以做到以下几点:

docker-compose.yml:

version: "3.4"
services:
  # your server docker container
  zmq_server:
    build:
      context: ./server_router_router
      dockerfile: Dockerfile

  # container that has to wait
  zmq_client:
    build:
      context: ./client_dealer/
      dockerfile: Dockerfile
    depends_on:
      - zmq_server
    healthcheck:
      test: "sh status.sh"
      start_period: 5s

status.sh:

#!/bin/sh

exit 0

这里发生的情况是，5秒后调用healthcheck。这将调用status.sh脚本，该脚本总是返回“No problem”。 我们只是让zmq_client容器在启动前等待5秒!

注意:重要的是你有版本:“3.4”。如果。4不在那里，docker-compose会抱怨。

重启:失败 这招对我有用吗

---
version: '2.1'
services:
  consumer:
    image: golang:alpine
    volumes:
      - ./:/go/src/srv-consumer
    working_dir: /go/src/srv-consumer
    environment:
      AMQP_DSN: "amqp://guest:guest@rabbitmq:5672"
    command: go run cmd/main.go
    links:
          - rabbitmq
    restart: on-failure

  rabbitmq:
    image: rabbitmq:3.7-management-alpine
    ports:
      - "15672:15672"
      - "5672:5672"