nginx docs + webhook debug

docs/REVERSE_PROXY.md

@@ -0,0 +1,41 @@
+## Reverse proxy configuration
+
+Submitted by [s33d1ing](https://github.com/s33d1ing).
+
+
+Reverse proxy example by using LinuxServer's SWAG container.
+
+### nginx config
+
+
+``` nginx
+location /pialert {
+    return 301 $scheme://$host/pialert/;
+}
+
+location ^~ /pialert/ {
+    include /config/nginx/proxy.conf;
+    include /config/nginx/resolver.conf;
+
+    set $upstream_app pialert;
+    set $upstream_port 20211;
+    set $upstream_proto http;
+
+    proxy_pass $upstream_proto://$upstream_app:$upstream_port;
+    proxy_set_header Accept-Encoding "";
+
+    proxy_redirect ~^/(.*)$ /pialert/$1;
+    rewrite ^/pialert/?(.*)$ /$1 break;
+
+    sub_filter_once off;
+    sub_filter_types *;
+
+    sub_filter 'href="/' 'href="/pialert/';
+
+    sub_filter '(?>$host)/css' '/pialert/css';
+    sub_filter '(?>$host)/img' '/pialert/img';
+    sub_filter '(?>$host)/js'  '/pialert/js';
+    sub_filter '(?>$host)/lib' '/pialert/lib';
+    sub_filter '(?>$host)/php' '/pialert/php';
+}
+```