Connect to configurable websocket service

services/web/app/views/project/editor.jade

@@ -80,7 +80,8 @@ block content
 	//- We need to do .replace(/\//g, '\\/') do that '</script>' -> '<\/script>'
 	//- and doesn't prematurely end the script tag.
 	script(type='text/javascript').
-		window.project_id = "!{project_id}"
+		window.project_id = "!{project_id}";
+		window.websocketsUrl = "!{settings.websocketsUrl}";
 		window.userSettings = !{JSON.stringify(userSettings).replace(/\//g, '\\/')};
 		window.user = !{JSON.stringify(user).replace(/\//g, '\\/')};
 		window.csrfToken = "!{csrfToken}";

services/web/config/settings.defaults.coffee

@@ -103,6 +103,14 @@ module.exports =
 			
 	templates:
 		user_id: process.env.TEMPLATES_USER_ID or "5395eb7aad1f29a88756c7f2"
+		
+	# The websocket layer of ShareLaTeX runs as separate service.
+	# When running locally or in development, you can point the client to this
+	# service directly. If you are running behind a reverse proxy (Nginx, etc)
+	# then websocketsUrl should be the same as siteUrl, with your reverse
+	# proxy responible for sending websocket traffic to the websocket service
+	# rather than connecting directly.
+	websocketsUrl: "http://localhost:3026"
 
 	# Where your instance of ShareLaTeX can be found publically. Used in emails
 	# that are sent out, generated links, etc.

services/web/public/coffee/ide/connection/ConnectionManager.coffee

@@ -14,7 +14,7 @@ define [], () ->
 			@$scope.$on "editor:change", () =>
 				@lastUpdated = new Date()
 
-			@ide.socket = io.connect null,
+			@ide.socket = io.connect window.websocketsUrl,
 				reconnect: false
 				"force new connection": true