nginx.conf

events {
  worker_connections 4096;
}

http {
  include /etc/nginx/mime.types;
  default_type application/octet-stream;

  upstream api_servers {
      #least_conn;
      server corinee_server_1:3000 weight=4 max_fails=3 fail_timeout=30s;
    #   server 223.130.134.167:3000 weight=8 max_fails=3 fail_timeout=30s;
    #   server 223.130.130.192:3000 weight=8 max_fails=3 fail_timeout=30s;
    #   server 211.188.59.137:3000 weight=8 max_fails=3 fail_timeout=30s;
    
      keepalive 300;
      keepalive_requests 1000;
      keepalive_timeout 75s;
  }

  server {
      listen 80;
      listen 443 ssl;
      server_name corinee.site www.corinee.site;

      ssl_certificate /etc/letsencrypt/live/corinee.site/fullchain.pem;
      ssl_certificate_key /etc/letsencrypt/live/corinee.site/privkey.pem;

      location / {
          root   /usr/share/nginx/html;
          index  index.html index.htm;
          try_files $uri $uri/ /index.html;
      }

      location /api {
          proxy_pass http://api_servers;
          proxy_next_upstream error timeout http_500 http_502 http_503 http_504;
          proxy_next_upstream_tries 3;
          proxy_next_upstream_timeout 10s;
          
          proxy_connect_timeout 10s;
          proxy_send_timeout 10s;
          proxy_read_timeout 10s;

          proxy_http_version 1.1;
          proxy_set_header Upgrade $http_upgrade;
          proxy_set_header Connection 'upgrade';
          proxy_set_header Host $host;
          proxy_cache_bypass $http_upgrade;
          proxy_set_header X-Real-IP $remote_addr;
          proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
          proxy_set_header X-Forwarded-Proto $scheme;
          proxy_set_header Origin $http_origin;
          
          proxy_set_header X-Server-Id $upstream_addr;
          add_header X-Served-By $upstream_addr;

          add_header 'Access-Control-Allow-Origin' 'https://www.corinee.site' always;
          add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS' always;
          add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization' always;
          add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range' always;
      }
  }
}