From fd95dbe75a0f09f07a3c3f0f51e8e9762554f474 Mon Sep 17 00:00:00 2001
From: Sam <sam.saffron@gmail.com>
Date: Tue, 14 Jan 2014 16:59:08 +1100
Subject: [PATCH] FEATURE: Automatically force a full refresh between pages if
 assets change

---
 app/assets/javascripts/discourse.js                 | 13 ++++++++++++-
 .../discourse/initializers/1_init_message_bus.js    |  3 +++
 app/assets/javascripts/discourse/lib/url.js         | 10 ++++++++++
 .../discourse/routes/application_route.js           |  6 ++++--
 app/views/common/_discourse_javascript.html.erb     |  1 +
 config/initializers/04-message_bus.rb               |  8 ++++++++
 6 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/app/assets/javascripts/discourse.js b/app/assets/javascripts/discourse.js
index 97f4f1a31..8ffa2e47a 100644
--- a/app/assets/javascripts/discourse.js
+++ b/app/assets/javascripts/discourse.js
@@ -128,7 +128,18 @@ window.Discourse = Ember.Application.createWithMixins(Discourse.Ajax, {
         }
       });
     }
-  }
+  },
+
+  assetVersion: function(prop, val) {
+    if(val) {
+      if(this.get("currentAssetVersion")){
+        this.set("desiredAssetVersion", val);
+      } else {
+        this.set("currentAssetVersion", val);
+      }
+    }
+    return this.get("currentAssetVersion");
+  }.property()
 
 });
 
diff --git a/app/assets/javascripts/discourse/initializers/1_init_message_bus.js b/app/assets/javascripts/discourse/initializers/1_init_message_bus.js
index d4397f535..fafac2aec 100644
--- a/app/assets/javascripts/discourse/initializers/1_init_message_bus.js
+++ b/app/assets/javascripts/discourse/initializers/1_init_message_bus.js
@@ -4,5 +4,8 @@
 Discourse.addInitializer(function() {
   Discourse.MessageBus.alwaysLongPoll = Discourse.Environment === "development";
   Discourse.MessageBus.start();
+  Discourse.MessageBus.subscribe("/global/asset-version", function(version){
+    Discourse.set("assetVersion",version);
+  });
   Discourse.KeyValueStore.init("discourse_", Discourse.MessageBus);
 }, true);
diff --git a/app/assets/javascripts/discourse/lib/url.js b/app/assets/javascripts/discourse/lib/url.js
index bf5b8f1b6..8d2789629 100644
--- a/app/assets/javascripts/discourse/lib/url.js
+++ b/app/assets/javascripts/discourse/lib/url.js
@@ -47,6 +47,16 @@ Discourse.URL = Em.Object.createWithMixins({
     @param {String} path The path we are routing to.
   **/
   routeTo: function(path) {
+
+    // If somehow our asset version changed, force a full reload of desired path
+    var desired = Discourse.get("desiredAssetVersion");
+    if(desired) {
+      if(Discourse.get("currentAssetVersion") !== desired){
+        document.location.href = path;
+        return;
+      }
+    }
+
     var oldPath = window.location.pathname;
     path = path.replace(/https?\:\/\/[^\/]+/, '');
 
diff --git a/app/assets/javascripts/discourse/routes/application_route.js b/app/assets/javascripts/discourse/routes/application_route.js
index be96c9ca8..babec6215 100644
--- a/app/assets/javascripts/discourse/routes/application_route.js
+++ b/app/assets/javascripts/discourse/routes/application_route.js
@@ -9,6 +9,7 @@
 Discourse.ApplicationRoute = Em.Route.extend({
 
   actions: {
+
     showLogin: function() {
       Discourse.Route.showModal(this, 'login');
       this.controllerFor('login').resetForm();
@@ -80,16 +81,17 @@ Discourse.ApplicationRoute = Em.Route.extend({
         });
       }
 
-    },
+    }
   },
 
   activate: function() {
     this._super();
-    Em.run.next(function() { 
+    Em.run.next(function() {
       // Support for callbacks once the application has activated
       Discourse.ApplicationRoute.trigger('activate');
     });
   }
+
 });
 
 RSVP.EventTarget.mixin(Discourse.ApplicationRoute);
diff --git a/app/views/common/_discourse_javascript.html.erb b/app/views/common/_discourse_javascript.html.erb
index ab3f91e42..cf3da5bec 100644
--- a/app/views/common/_discourse_javascript.html.erb
+++ b/app/views/common/_discourse_javascript.html.erb
@@ -37,6 +37,7 @@
   Discourse.SiteSettings = PreloadStore.get('siteSettings');
   Discourse.Router.map(function() { Discourse.routeBuilder.call(this); });
   Discourse.start()
+  Discourse.set('assetVersion','<%= Rails.application.assets.digest %>');
 </script>
 
 <%= javascript_include_tag 'browser-update.js' %>
diff --git a/config/initializers/04-message_bus.rb b/config/initializers/04-message_bus.rb
index efc333f2d..2768d625f 100644
--- a/config/initializers/04-message_bus.rb
+++ b/config/initializers/04-message_bus.rb
@@ -37,3 +37,11 @@ end
 
 MessageBus.cache_assets = !Rails.env.development?
 MessageBus.enable_diagnostics
+
+digest = Rails.application.assets.digest.to_s
+channel = "/global/asset-version"
+message = MessageBus.last_message(channel)
+
+unless message && message.data == digest
+  MessageBus.publish channel, digest
+end