Docker MySQL-无法从Spring Boot应用连接到MySQL数据库

我想做的是，从我的spring-boot应用程序连接到Docker中的mysql数据库。每个都放在自己的容器中。

但是我一定做错了，因为我做不到。

为了简单起见：

应用程序属性：

# URL for the mysql db
spring.datasource.url=jdbc:mysql://workaround-mysql:3308/workaround?serverTimezone=UTC&max_allowed_packet=15728640
# User name in mysql
spring.datasource.username=springuser
# Password for mysql
spring.datasource.password=admin
#Port at which application runs
server.port=8080

docker-compose for MySQL：

version: '3'
services:
  workaround-mysql:
    container_name: workaround-mysql
    image: mysql
    environment:
      MYSQL_DATABASE: workaround
      MYSQL_USER: springuser
      MYSQL_PASSWORD: admin
      MYSQL_ROOT_PASSWORD: admin
      MYSQL_ROOT_HOST: '%'
    ports:
      - "3308:3306"
    restart: always

很简单吧？我从数据库开始docker-compose up：

到目前为止，一切似乎工作正常。

现在，我已经启动了db，对于应用程序，这是它的docker-compose.yml：

version: '3'
services:

  workaround:
    restart: always
    # will build ./docker/workaround/Dockerfile
    build: ./docker/workaround
    working_dir: /workaround
    volumes:
      - ./:/workaround
      - ~/.m2:/root/.m2
    expose:
      - "8080"
    command: "mvn clean spring-boot:run"

对于它，Dockerfile我使用Linux Alpine和Java。

FROM alpine:3.9
....add java...
RUN apk update
RUN apk add dos2unix --update-cache --repository http://dl-3.alpinelinux.org/alpine/edge/community/ --allow-untrusted
RUN apk add bash
RUN apk add maven

超级简单。现在让我们启动应用程序：

未知的主机，所以让我们尝试IP：

    docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' workaround-mysql

# URL for the mysql db
spring.datasource.url=jdbc:mysql://172.20.0.2:3308/workaround?serverTimezone=UTC&max_allowed_packet=15728640

现在我超时了：

As you can see I get error. What is wrong with my setup and how to fix this? Either I have unknown host exception or Refused to connect or connection timeout.

I have tried:

• Using ip of a container in my application.properties, didn't work
• Different ports for MySQL and application
• Different images and versions of MySQL
• Having everything in one docker compose with wait
• timer for database.
• Minimal setup with https://github.com/hellokoding/hellokoding-courses/tree/master/docker-examples/dockercompose-springboot-mysql-nginx Also resulted in communication link failure, Site was accessible but I doubt that db was connected properly.

Notes:

• I run this all on one computer I use port 3308 because I have local MySQL db at 3306.

• Here is docker ps -a

@Vusal ANSWER output :

唯一与答案中的代码不同的事情是我等待数据库准备就绪30秒

command: /bin/bash -c "sleep 30;mvn clean spring-boot:run;"