我的docker-compose.yml内容如下：

version: "3"
services:
  my_server:
    build: .
    restart: always
    depends_on:
      mysql:
        condition: service_started
    ports:
      - 9999:9999
    links:
      - mysql

  mysql:
    image: mysql:latest # mysql:oracle
    restart: always
    container_name: mysql
    command: 
      - --lower_case_table_names=1
    ports:
      - 3306:3306
    volumes:
      - ./init.sql:/docker-entrypoint-initdb.d/setup.sql
    environment:
      - MYSQL_ROOT_PASSWORD=123456

Dockerfile内容如下：

FROM sanicframework/sanic:3.8-latest

WORKDIR /sanic/my_server

COPY . /sanic/my_server

COPY . .

RUN pip install -r requirements.txt

EXPOSE 9999

CMD ["python", "main.py"]

使用docker-compose.yml部署项目时候，提示

RuntimeError:‘cryptography’ package isrequired for sha256_password or caching_sha2_password，

出现的原因是mysql8.0+版本使用了新的密码校验插件，需要安装cryptography这个库，

当你在requirement.txt加上cryptography==39.0.1后，重新运行docker compose up这条命令时候，又出现如下错误

也就是说，安装cryptography这个库的时候，下载依赖出现问题，解决这个问题就是安装一些必备的库，在Dockerfile文件添加以下内容

RUN apk update

RUN apk --update add gcc musl-dev libffi-dev openssl-dev 

RUN apk add gcc musl-dev python3-dev libffi-dev openssl-dev cargo

RUN pip install -r requirements.txt

EXPOSE 9999

RUN apk del --purge gcc musl-dev libffi-dev openssl-dev

就可以解决问题,完整的dockerfile如下：

FROM sanicframework/sanic:3.8-latest

WORKDIR /sanic/my_server

COPY . /sanic/my_server

COPY . .

RUN apk update

RUN apk --update add gcc musl-dev libffi-dev openssl-dev 

RUN apk add gcc musl-dev python3-dev libffi-dev openssl-dev cargo

RUN pip install -r requirements.txt

EXPOSE 9999

RUN apk del --purge gcc musl-dev libffi-dev openssl-dev

CMD ["python", "main.py"]