server {
  listen 80;
  root /usr/share/nginx/html;
  resolver 127.0.0.11 valid=5s ipv6=off;

  location /api/ {
    set $api_upstream api:8000;
    proxy_pass http://$api_upstream;
    proxy_http_version 1.1;
    # Preserve SSE delivery and WebSocket upgrades.
    proxy_buffering off;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection $connection_upgrade;
    proxy_set_header Host $host;
    proxy_set_header X-Forwarded-Proto $http_x_forwarded_proto;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_read_timeout 1h;
  }

  location /assets/ {
    expires 1y;
    add_header Cache-Control "public, immutable";
  }

  location / {
    try_files $uri $uri/ /index.html;
    add_header Cache-Control "no-cache";
  }
}

map $http_upgrade $connection_upgrade {
  default upgrade;
  "" "";
}