Update index.md (#297)

Added Apache reverse proxy example configuration

doc/self-hosted/index.md

@@ -90,5 +90,29 @@ OPTIONS
    }
   ```
   
+  ### Apache Reverse Proxy
+  Example of https virtualhost configuration for Apache as a reverse proxy. Please also pass --allow-http on code-server startup to allow the proxy to connect.
+  ```
+  <VirtualHost *:80>
+    ServerName code.example.com
+
+    RewriteEngine On
+    RewriteCond %{HTTP:Upgrade} =websocket [NC]
+    RewriteRule /(.*)           ws://localhost:8443/$1 [P,L]
+    RewriteCond %{HTTP:Upgrade} !=websocket [NC]
+    RewriteRule /(.*)           http://localhost:8443/$1 [P,L]
+    
+    ProxyRequests off
+
+    RequestHeader set X-Forwarded-Proto https
+    RequestHeader set X-Forwarded-Port 443
+
+    ProxyPass / http://localhost:8443/ nocanon
+    ProxyPassReverse / http://localhost:8443/
+
+  </VirtualHost>
+  ```
+  *Important:* For more details about Apache reverse proxy configuration checkout the [documentation](https://httpd.apache.org/docs/current/mod/mod_proxy.html) - especially the [Securing your Server](https://httpd.apache.org/docs/current/mod/mod_proxy.html#access) section
+  
   ### Help
   Use `code-server -h` or `code-server --help` to view the usage for the cli. This is also shown at the beginning of this section.