Example of Nginx configuration file for HTTPS proxy to a nodejs server.

nginx-node-conf

#
# nginx configuration file for HTTPS proxy to a nodejs server.
#   1. obtain an SSL certificate from letsencrypt (https://letsencrypt.org)
#   2. copy this file to /etc/nginx/site-available;
#   3. create an alias for nginx: ln -s /etc/nginx/site-available/example.com /etc/nginx/site-enabled
#   4. restart nginx: sudo service nginx restart
#

# HTTP - redirect all requests to HTTPS:
server {
    listen 80;
    listen [::]:80 default_server ipv6only=on;
    server_name <example.com>; # replace <example.com> by your domain name
    return 301 https://$host$request_uri;
}

# HTTPS - proxy requests on to local Node.js app:
server {
  listen 443;
  server_name <example.com>; # replace <example.com> by your domain name
  client_max_body_size 4000M; # maximum upload size
  proxy_request_buffering off; # stream multipart form to the backend in real-time

  ssl on;
  # Use certificate and key provided by Let's Encrypt:
  ssl_certificate /etc/letsencrypt/live/<example.com>/fullchain.pem; # replace <example.com> by your domain name
  ssl_certificate_key /etc/letsencrypt/live/<example.com>/privkey.pem; # replace <example.com> by your domain name
  ssl_session_timeout 5m;
  ssl_protocols TLSv1.2 TLSv1.23;
  ssl_prefer_server_ciphers on;
  ssl_ciphers 'EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH';
  ssl_dhparam /etc/ssl/certs/dhparam.pem;
  add_header Strict-Transport-Security "max-age=63072000; includeSubdomains; ";

  # Pass requests for / to the nodejs server:
  location / {
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-NginX-Proxy true;
    proxy_pass http://localhost:<port>; # replace <port> with the port number on which your nodejs server runs
    proxy_ssl_session_reuse off;
    proxy_set_header Host $http_host;
    proxy_cache_bypass $http_upgrade;
    proxy_redirect off;
  }
}

listen 443 ssl;
http2 on;