From 3e71b4e4841279c74f03cd62ab59c0d46b7bbc57 Mon Sep 17 00:00:00 2001
From: Martin Edenhofer <me@edenhofer.de>
Date: Sat, 4 Aug 2012 15:35:55 +0200
Subject: [PATCH] Added ping connection feature.

---
 .../javascripts/app/lib/websocket.js.coffee   | 31 ++++++++++++++++++-
 script/websocket-server.rb                    | 11 +++++--
 2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/app/assets/javascripts/app/lib/websocket.js.coffee b/app/assets/javascripts/app/lib/websocket.js.coffee
index 5937b5135..3d51fe09b 100644
--- a/app/assets/javascripts/app/lib/websocket.js.coffee
+++ b/app/assets/javascripts/app/lib/websocket.js.coffee
@@ -7,6 +7,10 @@ class App.WebSocket
       _instance ?= new _Singleton
     _instance
 
+  @close: (args) -> # Must be a static method
+    if _instance isnt undefined
+      _instance.close()
+
   @send: (args) -> # Must be a static method
     @connect()
     _instance.send(args)
@@ -48,6 +52,24 @@ class _Singleton extends Spine.Controller
   close: =>
     @ws.close()
 
+  ping: =>
+    console.log 'send websockend ping'
+    @send( { action: 'ping' } )
+
+    # check if ping is back within 30 sec.
+    if @check_id
+      clearTimeout(@check_id)
+    check = =>
+      console.log 'no websockend ping response, reconnect...'
+      @close()
+    @check_id = @delay check, 60000
+
+  pong: ->
+    console.log 'received websockend ping'
+
+    # test again after 10 sec.
+    @delay @ping, 30000
+
   connect: =>
 #    console.log '------------ws connect....--------------'
 
@@ -80,13 +102,20 @@ class _Singleton extends Spine.Controller
         @send(item)
       @queue = []
 
-    @ws.onmessage = (e) ->
+      # send ping to check connection
+      @delay @ping, 30000
+
+    @ws.onmessage = (e) =>
       pipe = JSON.parse( e.data )
       console.log( "ws:onmessage", pipe )
 
       # go through all blocks
       for item in pipe
 
+        # reset reconnect loop
+        if item['action'] is 'pong'
+          @pong()
+
         # fill collection
         if item['collection']
           console.log( "ws:onmessage collection:" + item['collection'] )
diff --git a/script/websocket-server.rb b/script/websocket-server.rb
index 10991eaee..89888639a 100644
--- a/script/websocket-server.rb
+++ b/script/websocket-server.rb
@@ -59,10 +59,12 @@ EventMachine.run {
     ws.onclose {
       client_id = ws.object_id
       puts 'Client ' + client_id.to_s + ' disconnected'
-      
+
+      # removed from current client list
       if @clients.include? client_id
         @clients.delete client_id
       end
+
       Session.destory( client_id )
     }
 
@@ -77,7 +79,12 @@ EventMachine.run {
       if data['action'] == 'login'
         @clients[client_id][:session] = data['session']
         Session.create( client_id, data['session'] )
-      end 
+
+      # ping
+      elsif data['action'] == 'ping'
+        @clients[client_id][:last_ping] = Time.now
+        ws.send( '[{"action":"pong"}]' )
+      end
     }
   end