docs: reverse proxy example

README.md

@@ -44,7 +44,7 @@ https://hub.docker.com/repository/docker/scsibug/nostr-rs-relay
 
 ## Configuration
 
-The sample `[config.toml](config.toml)` file demonstrates the
+The sample [`config.toml`](config.toml) file demonstrates the
 configuration available to the relay.  This file is optional, but may
 be mounted into a docker container like so:
 
@@ -58,6 +58,12 @@ $ docker run -it -p 7000:8080 \
 Options include rate-limiting, event size limits, and network address
 settings.
 
+## Reverse Proxy Configuration
+
+For examples of putting the relay behind a reverse proxy (for TLS
+termination, load balancing, and other features), see [Reverse
+Proxy](reverse-proxy.md).
+
 License
 ---
 This project is MIT licensed.

reverse-proxy.md

@@ -0,0 +1,48 @@
+# Reverse Proxy Setup Guide
+
+It is recommended to run `nostr-rs-relay` behind a reverse proxy such
+as `haproxy` or `nginx` to provide TLS termination.  A simple example
+of an `haproxy` configuration is documented here.
+
+## Minimal HAProxy Configuration
+
+Assumptions:
+
+* HAProxy version is `2.4.10` or greater (older versions not tested).
+* Hostname for the relay is `relay.example.com`.
+* Your relay should be available over wss://relay.example.com
+* Your (NIP-11) relay info page should be available on https://relay.example.com
+* SSL certificate is located in `/etc/certs/example.com.pem`.
+* Relay is running on port 8080.
+* Limit connections to 400 concurrent.
+* HSTS (HTTP Strict Transport Security) is desired.
+* Only TLS 1.2 or greater is allowed.
+
+```
+global
+    ssl-default-bind-ciphersuites TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256
+    ssl-default-bind-options prefer-client-ciphers no-sslv3 no-tlsv10 no-tlsv11 no-tls-tickets
+
+frontend fe_prod
+    mode    http
+    bind    :443 ssl crt /etc/certs/example.com.pem alpn h2,http/1.1
+    bind    :80
+    http-request set-header X-Forwarded-Proto https if { ssl_fc }
+    redirect scheme https code 301 if !{ ssl_fc }
+    acl host_relay hdr(host) -i relay.example.com
+    use_backend relay if host_relay
+    # HSTS (1 year)
+    http-response set-header Strict-Transport-Security max-age=31536000
+
+backend relay
+    mode http
+    option tcp-check
+    default-server maxconn 400 check inter 20s fastinter 1s
+    server nostr 127.0.0.1:8080
+```
+
+### Notes
+
+You may experience WebSocket connection problems with Firefox if
+HTTP/2 is enabled, for older versions of HAProxy (2.3.x).  Either
+disable HTTP/2 (`h2`), or upgrade HAProxy.