Docker系统性入门（三）

可以在yml文件中设置环境变量，就是environment，这个例子里主要是给用

version: "3.8"

services:
  flask:
    build:
      context: ./flask
      dockerfile: Dockerfile
    image: flask-demo:latest
    environment:
      - REDIS_HOST=redis-server
      - REDIS_PASS=${REDIS_PASSWORD}
    networks:
      - backend
      - frontend

  redis-server:
    image: redis:latest
    # redis-server redis-cli是redis定义的命令
    command: redis-server --requirepass ${REDIS_PASSWORD}
    networks:
      - backend

  nginx:
    image: nginx:stable-alpine
    ports:
      - 8000:80
    depends_on:
      - flask
    volumes:
      - ./nginx/:/etc/nginx//:ro
      - ./var/log/nginx:/var/log/nginx
    networks:
      - frontend

networks:
  backend:
  frontend:

# 
from flask import Flask
from redis import StrictRedis
import os
import socket

app = Flask(__name__)
redis = StrictRedis(host=os.environ.get('REDIS_HOST', '127.0.0.1'),
                    port=6379, password=os.environ.get('REDIS_PASS'))


@app.route('/')
def hello():
    redis.incr('hits')
    return f"Hello Container World! I have been seen {redis.get('hits').decode('utf-8')} times and my hostname is {socket.gethostname()}.\n"

• 执行：docker-compose up -d --build，不太智能了，你改了py没给你build直接用的缓存image