连接到上游 Nginx Docker 时连接被拒绝

Question

我正在尝试在 docker 中构建一个 FastAPI 应用程序，我发现该站点出现“502-Bad Gate Way”错误并且 nginx 日志显示：

nginx_1    | 2020/12/21 18:23:13 [error] 29#29: *1 connect() failed (111: Connection refused) while connecting to upstream, client: 172.27.0.1, server: , request: "GET /user HTTP/1.1", upstream: "http://172.27.0.3:8000/user", host: "localhost:8080"

这是我的 docker-compose.yaml 文件：

version: '3.7'

services:
  fastapi:
    build: ./api
    command: uvicorn main:app --reload --host 0.0.0.0 --port 8000
    volumes:
      - ./fastapi/:/fastapi/
    ports:
      - 8000:8000
    depends_on:
      - db

  db:
    image: mongo:latest
    container_name: mongo4
    ports:
      - "27017:27017"
    volumes:
      - "./data/mongo/data:/data/db"

  nginx:
    image: nginx:latest
    ports:
      - "8080:8080"
    volumes:
      - ./nginx_config.conf:/etc/nginx/conf.d/default.conf
    depends_on:
      - fastapi

Nginx 配置文件：

server {
  listen 8080;

  location /user {
    proxy_pass http://fastapi:8000/user;
  }
}

感谢您的帮助。