hedgedoc/docs/content/guides/reverse-proxy.md
Matt Fisher 74b573e414 Add a warning about an NGINX pitfall and its symptom in HedgeDoc
Signed-off-by: Matt Fisher <matt.fisher@nsidc.org>
2023-10-07 18:06:07 +02:00

4.9 KiB

Using a Reverse Proxy with HedgeDoc

If you want to use a reverse proxy to serve HedgeDoc, here are the essential configs that you'll have to do.

This documentation will cover HTTPS setup, with comments for HTTP setup.

Cloudflare

!!! warning If you use Cloudflare as reverse proxy then you MUST disable the minify features for HTML, CSS and JS, or your HedgeDoc instance may be broken. For more information please read the Cloudflare documentation.

HedgeDoc config

Useful configuration options

config.json parameter Environment variable Value Example
domain CMD_DOMAIN The full domain where your instance will be available hedgedoc.example.com
host CMD_HOST An ip or domain name that is only available to HedgeDoc and your reverse proxy localhost
port CMD_PORT An available port number on that IP 3000
path CMD_PATH path to UNIX domain socket to listen on (if specified, host or CMD_HOST and port or CMD_PORT are ignored) /var/run/hedgedoc.sock
protocolUseSSL CMD_PROTOCOL_USESSL true if you want to serve your instance over SSL (HTTPS), false if you want to use plain HTTP true
useSSL false, the communications between HedgeDoc and the proxy are unencrypted false
urlAddPort CMD_URL_ADDPORT false, HedgeDoc should not append its port to the URLs it links false
hsts.enable CMD_HSTS_ENABLE true if you host over SSL, false otherwise true

Full explanation of the configuration options

HedgeDoc generates links to other pages and to assets (like images, stylesheets, fonts, etc) using the following settings. You must configure them according to the URL that you use to access your instance.

  • domain (env: CMD_DOMAIN)
  • protocolUseSSL (env: CMD_PROTOCOL_USESSL)
  • urlAddPort (env: CMD_URL_ADDPORT)

!!! example You access your HedgeDoc instance using a reverse proxy via https://markdown.example. You must set:

- `domain` to `markdown.example`.
- `protocolUseSSL` to `true` because you access your instance via HTTPS.
- `urlAddPort` to `false` because you access the instance using the default HTTPS port.

Reverse Proxy config

Generic

The reverse proxy must allow websocket Upgrade requests at path /sockets.io/.

It must pass through the scheme used by the client (http or https).

Nginx

Here is an example configuration for Nginx.

map $http_upgrade $connection_upgrade {
        default upgrade;
        ''      close;
}
server {
        server_name hedgedoc.example.com;

        location / {
                proxy_pass http://127.0.0.1:3000;
                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;
        }

        location /socket.io/ {
                proxy_pass http://127.0.0.1:3000;
                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;
                proxy_set_header Upgrade $http_upgrade;
                proxy_set_header Connection $connection_upgrade;
        }

    listen [::]:443 ssl http2;
    listen 443 ssl http2;
    ssl_certificate fullchain.pem;
    ssl_certificate_key privkey.pem;
    include options-ssl-nginx.conf;
    ssl_dhparam ssl-dhparams.pem;
}

!!! warning

NGINX `proxy_pass` directives must NOT have trailing slashes. If the trailing
slashes are present, the browser will not be able to establish a WebSocket
connection to the server, and the editor interface will display an endless loading
animation.

Apache

You will need these modules enabled: proxy, proxy_http and proxy_wstunnel.
Here is an example config snippet:

<VirtualHost *:443>
  ServerName hedgedoc.example.com

  RewriteEngine on
  RewriteCond %{REQUEST_URI} ^/socket.io             [NC]
  RewriteCond %{HTTP:Upgrade} =websocket             [NC]
  RewriteRule /(.*)  ws://127.0.0.1:3000/$1          [P,L]

  ProxyPass / http://127.0.0.1:3000/
  ProxyPassReverse / http://127.0.0.1:3000/

  RequestHeader set "X-Forwarded-Proto" expr=%{REQUEST_SCHEME}
        
  ErrorLog ${APACHE_LOG_DIR}/error.log
  CustomLog ${APACHE_LOG_DIR}/access.log combined

  SSLCertificateFile /etc/letsencrypt/live/hedgedoc.example.com/fullchain.pem
  SSLCertificateKeyFile /etc/letsencrypt/live/hedgedoc.example.com/privkey.pem
  Include /etc/letsencrypt/options-ssl-apache.conf
</VirtualHost>