nginx.conf

user root;
events { worker_connections 1024; }
worker_processes auto;
error_log /var/log/nginx/error.log warn;
pid /tmp/nginx.pid;  # <- change here

http {
    client_body_temp_path /tmp/client_body 1 2;
    proxy_temp_path       /tmp/proxy_temp 1 2;
    fastcgi_temp_path     /tmp/fastcgi_temp 1 2;
    uwsgi_temp_path       /tmp/uwsgi_temp 1 2;
    scgi_temp_path        /tmp/scgi_temp 1 2;

    client_body_timeout 36000s;
    client_header_timeout 36000s;
    send_timeout 36000s;
    keepalive_timeout 36000s;

    proxy_connect_timeout 36000s;
    proxy_read_timeout 36000s;
    proxy_send_timeout 36000s;

    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;
    sendfile      on;

    proxy_buffering off;
    client_max_body_size 200M;

    # WebSocket upgrade mapping (must be in http context)
    map $http_upgrade $connection_upgrade {
        default upgrade;
        ''      close;
    }

    upstream app_http {
        server 127.0.0.1:3000;
    }

    upstream renderer {
        server 127.0.0.1:8083;
    }

    server {
        listen 8080;
        server_name _;

        # /api/render-sync/** -> internal 8083
        location ^~ /api/render-sync {
            proxy_pass http://renderer$request_uri;
            proxy_http_version 1.1;
            proxy_set_header Host $host;
            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;

            # WebSocket headers
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection $connection_upgrade;

            proxy_buffering off;
        }

        #/api/jobs and /api/jobs/** -> internal 8083
        location ^~ /api/v2 {
            proxy_pass http://renderer$request_uri;
            proxy_http_version 1.1;
            proxy_set_header Host $host;
            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;

            # WebSocket headers
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection $connection_upgrade;

            proxy_buffering off;
        }

        #/api/jobs and /api/jobs/** -> internal 8083
        location ^~ /api/jobs {
            proxy_pass http://renderer$request_uri;
            proxy_http_version 1.1;
            proxy_set_header Host $host;
            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;

            # WebSocket headers
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection $connection_upgrade;

            proxy_buffering off;
        }

        # all other requests -> internal 3000
        location / {
            proxy_pass http://app_http;
            proxy_http_version 1.1;
            proxy_set_header Host $host;
            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;

            # WebSocket headers
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection $connection_upgrade;

            proxy_buffering off;
        }
    }
}