无法访问 server_name 定义的域

Question

我正在尝试将我的后端服务器映射到http://api:4000，my-domain.site其中api是我的后端服务在 docker compose 中的名称。

我运行 docker compose up 并且一切正常，但我只能访问我的后端服务器localhost，而不能访问我想要的域my-domain.site。

以下是我的docker-compose.yml文件和 nginx 配置文件：

docker-compose.yml

nginx:
    image: nginx:alpine
    container_name: nginx
    restart: always
    ports:
      - "80:80"
      - "443:443"
    command: nginx -g "daemon off;"
    volumes:
      - ./conf.d:/etc/nginx/conf.d
      - ./hosts:/etc/hosts
    depends_on:
      - api

api:
    container_name: backend
    build:
      context: ./backend
      dockerfile: Dockerfile
    command: npm start
    ports:
      - "4000:4000"

conf.d/default.conf

server {
  listen 80;
  server_name my-domain.site;
  location / {
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header Host $host;
    proxy_pass http://api:4000;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
  }
}