Deprecates global use of `Discourse.MessageBus`

We can use DI for this, which makes it easier for plugins to subscribe
to the message bus.

app/assets/javascripts/admin/routes/admin-backups.js.es6

@@ -1,11 +1,11 @@
 import showModal from 'discourse/lib/show-modal';
 
+const LOG_CHANNEL = "/admin/backups/logs";
+
 export default Discourse.Route.extend({
 
-  LOG_CHANNEL: "/admin/backups/logs",
-
   activate() {
-    Discourse.MessageBus.subscribe(this.LOG_CHANNEL, this._processLogMessage.bind(this));
+    this.messageBus.subscribe(LOG_CHANNEL, this._processLogMessage.bind(this));
   },
 
   _processLogMessage(log) {
@@ -40,7 +40,7 @@ export default Discourse.Route.extend({
   },
 
   deactivate() {
-    Discourse.MessageBus.unsubscribe(this.LOG_CHANNEL);
+    this.messageBus.unsubscribe(LOG_CHANNEL);
   },
 
   actions: {

app/assets/javascripts/discourse/controllers/topic.js.es6

@@ -563,7 +563,7 @@ export default ObjectController.extend(Discourse.SelectedPostsCount, BufferedCon
     this.unsubscribe();
 
     const self = this;
-    Discourse.MessageBus.subscribe("/topic/" + this.get('id'), function(data) {
+    this.messageBus.subscribe("/topic/" + this.get('id'), function(data) {
       const topic = self.get('model');
 
       if (data.notification_level_change) {
@@ -605,7 +605,7 @@ export default ObjectController.extend(Discourse.SelectedPostsCount, BufferedCon
     if (!topicId) return;
 
     // there is a condition where the view never calls unsubscribe, navigate to a topic from a topic
-    Discourse.MessageBus.unsubscribe('/topic/*');
+    this.messageBus.unsubscribe('/topic/*');
   },
 
   // Topic related

app/assets/javascripts/discourse/initializers/asset-version.js.es6

@@ -1,15 +1,14 @@
-/**
-  Subscribe to "asset-version" change events via the Message Bus
-**/
+//  Subscribe to "asset-version" change events via the Message Bus
 export default {
   name: "asset-version",
   after: "message-bus",
 
-  initialize: function () {
-    var timeoutIsSet = false;
-    if (!Discourse.MessageBus) { return; }
+  initialize(container) {
+    let timeoutIsSet = false;
+    const messageBus = container.lookup('message-bus:main');
+    if (!messageBus) { return; }
 
-    Discourse.MessageBus.subscribe("/global/asset-version", function (version) {
+    messageBus.subscribe("/global/asset-version", function (version) {
       Discourse.set("assetVersion", version);
 
       if (!timeoutIsSet && Discourse.get("requiresRefresh")) {

app/assets/javascripts/discourse/initializers/banner.js.es6

@@ -2,15 +2,16 @@ export default {
   name: "banner",
   after: "message-bus",
 
-  initialize: function (container) {
-    var banner = Em.Object.create(PreloadStore.get("banner")),
-        site = container.lookup('site:main');
+  initialize(container) {
+    const banner = Em.Object.create(PreloadStore.get("banner")),
+          site = container.lookup('site:main');
 
     site.set("banner", banner);
 
-    if (!Discourse.MessageBus) { return; }
+    const messageBus = container.lookup('message-bus:main');
+    if (!messageBus) { return; }
 
-    Discourse.MessageBus.subscribe("/site/banner", function (banner) {
+    messageBus.subscribe("/site/banner", function (banner) {
       site.set("banner", Em.Object.create(banner));
     });
   }

app/assets/javascripts/discourse/initializers/inject-objects.js.es6

@@ -2,53 +2,49 @@ import Session from 'discourse/models/session';
 import AppEvents from 'discourse/lib/app-events';
 import Store from 'discourse/models/store';
 
+function inject() {
+  const app = arguments[0],
+        name = arguments[1],
+        singletonName = Ember.String.underscore(name).replace(/_/, '-') + ':main';
+
+  Array.prototype.slice.call(arguments, 2).forEach(function(dest) {
+    app.inject(dest, name, singletonName);
+  });
+}
+
+function injectAll(app, name) {
+  inject(app, name, 'controller', 'component', 'route', 'view', 'model');
+}
+
 export default {
   name: "inject-objects",
   initialize(container, app) {
 
-    // Inject appEvents everywhere
     const appEvents = AppEvents.create();
     app.register('app-events:main', appEvents, { instantiate: false });
-
-    app.inject('controller', 'appEvents', 'app-events:main');
-    app.inject('component', 'appEvents', 'app-events:main');
-    app.inject('route', 'appEvents', 'app-events:main');
-    app.inject('view', 'appEvents', 'app-events:main');
-    app.inject('model', 'appEvents', 'app-events:main');
+    injectAll(app, 'appEvents');
     Discourse.URL.appEvents = appEvents;
 
     // Inject Discourse.Site to avoid using Discourse.Site.current()
     const site = Discourse.Site.current();
     app.register('site:main', site, { instantiate: false });
-    app.inject('controller', 'site', 'site:main');
-    app.inject('component', 'site', 'site:main');
-    app.inject('route', 'site', 'site:main');
-    app.inject('view', 'site', 'site:main');
-    app.inject('model', 'site', 'site:main');
+    injectAll(app, 'site');
 
     // Inject Discourse.SiteSettings to avoid using Discourse.SiteSettings globals
     app.register('site-settings:main', Discourse.SiteSettings, { instantiate: false });
-    app.inject('controller', 'siteSettings', 'site-settings:main');
-    app.inject('component', 'siteSettings', 'site-settings:main');
-    app.inject('route', 'siteSettings', 'site-settings:main');
-    app.inject('view', 'siteSettings', 'site-settings:main');
-    app.inject('model', 'siteSettings', 'site-settings:main');
+    injectAll(app, 'siteSettings');
 
     // Inject Session for transient data
     app.register('session:main', Session.current(), { instantiate: false });
-    app.inject('controller', 'session', 'session:main');
-    app.inject('component', 'session', 'session:main');
-    app.inject('route', 'session', 'session:main');
-    app.inject('view', 'session', 'session:main');
-    app.inject('model', 'session', 'session:main');
+    injectAll(app, 'session');
 
     app.register('current-user:main', Discourse.User.current(), { instantiate: false });
-    app.inject('component', 'currentUser', 'current-user:main');
-    app.inject('route', 'currentUser', 'current-user:main');
-    app.inject('controller', 'currentUser', 'current-user:main');
+    inject(app, 'currentUser', 'component', 'route', 'controller');
+
+    app.register('message-bus:main', window.MessageBus, { instantiate: false });
+    inject(app, 'messageBus', 'route', 'controller');
 
     app.register('store:main', Store);
-    app.inject('route', 'store', 'store:main');
-    app.inject('controller', 'store', 'store:main');
+    inject(app, 'store', 'route', 'controller');
   }
 };

app/assets/javascripts/discourse/initializers/live-development.js.es6

@@ -3,7 +3,8 @@ import loadScript from 'discourse/lib/load-script';
 //  Use the message bus for live reloading of components for faster development.
 export default {
   name: "live-development",
-  initialize() {
+  initialize(container) {
+    const messageBus = container.lookup('message-bus:main');
 
     // subscribe to any site customizations that are loaded
     $('link.custom-css').each(function() {
@@ -11,7 +12,7 @@ export default {
           id = split[split.length - 1].split(".css")[0],
           self = this;
 
-      return Discourse.MessageBus.subscribe("/file-change/" + id, function(data) {
+      return messageBus.subscribe("/file-change/" + id, function(data) {
         if (!$(self).data('orig')) {
           $(self).data('orig', self.href);
         }
@@ -24,13 +25,13 @@ export default {
     // Custom header changes
     $('header.custom').each(function() {
       const header = $(this);
-      return Discourse.MessageBus.subscribe("/header-change/" + $(this).data('key'), function(data) {
+      return messageBus.subscribe("/header-change/" + $(this).data('key'), function(data) {
         return header.html(data);
       });
     });
 
     // Observe file changes
-    Discourse.MessageBus.subscribe("/file-change", function(data) {
+    messageBus.subscribe("/file-change", function(data) {
       Ember.TEMPLATES.empty = Handlebars.compile("<div></div>");
       _.each(data,function(me) {
 

app/assets/javascripts/discourse/initializers/logout.js.es6

@@ -1,16 +1,17 @@
-/**
-  Subscribe to "logout" change events via the Message Bus
-**/
+//  Subscribe to "logout" change events via the Message Bus
 export default {
   name: "logout",
   after: "message-bus",
 
-  initialize: function () {
-    if (!Discourse.MessageBus) { return; }
+  initialize: function (container) {
+    const messageBus = container.lookup('message-bus:main'),
+          siteSettings = container.lookup('site-settings:main');
 
-    Discourse.MessageBus.subscribe("/logout", function () {
+    if (!messageBus) { return; }
+
+    messageBus.subscribe("/logout", function () {
       var refresher = function() {
-        var redirect = Discourse.SiteSettings.logout_redirect;
+        var redirect = siteSettings.logout_redirect;
         if(redirect.length === 0){
           window.location.pathname = Discourse.getURL('/');
         } else {

app/assets/javascripts/discourse/initializers/message-bus.js.es6

@@ -1,17 +1,24 @@
-/**
-  Initialize the message bus to receive messages.
-**/
+// Initialize the message bus to receive messages.
 export default {
   name: "message-bus",
   after: 'inject-objects',
 
-  initialize: function() {
-
+  initialize(container) {
     // We don't use the message bus in testing
     if (Discourse.testing) { return; }
 
-    Discourse.MessageBus.alwaysLongPoll = Discourse.Environment === "development";
-    Discourse.MessageBus.start();
-    Discourse.KeyValueStore.init("discourse_", Discourse.MessageBus);
+    const messageBus = container.lookup('message-bus:main');
+
+    const deprecatedBus = {};
+    deprecatedBus.prototype = messageBus;
+    deprecatedBus.subscribe = function() {
+      Ember.warn("Discourse.MessageBus is deprecated. Use `this.messageBus` instead");
+      messageBus.subscribe.apply(messageBus, Array.prototype.slice(arguments));
+    };
+    Discourse.MessageBus = deprecatedBus;
+
+    messageBus.alwaysLongPoll = Discourse.Environment === "development";
+    messageBus.start();
+    Discourse.KeyValueStore.init("discourse_", messageBus);
   }
 };

app/assets/javascripts/discourse/initializers/read-only.js.es6

@@ -1,15 +1,14 @@
-/**
-  Subscribe to "read-only" status change events via the Message Bus
-**/
+// Subscribe to "read-only" status change events via the Message Bus
 export default {
   name: "read-only",
   after: "message-bus",
 
-  initialize: function (container) {
-    if (!Discourse.MessageBus) { return; }
+  initialize(container) {
+    const messageBus = container.lookup('message-bus:main');
+    if (!messageBus) { return; }
 
-    var site = container.lookup('site:main');
-    Discourse.MessageBus.subscribe("/site/read-only", function (enabled) {
+    const site = container.lookup('site:main');
+    messageBus.subscribe("/site/read-only", function (enabled) {
       site.set('isReadOnly', enabled);
     });
   }

app/assets/javascripts/discourse/initializers/subscribe-user-notifications.js.es6

@@ -1,16 +1,13 @@
-/**
-   Subscribes to user events on the message bus
-**/
+// Subscribes to user events on the message bus
 export default {
   name: 'subscribe-user-notifications',
   after: 'message-bus',
-  initialize: function(container) {
-    var user = Discourse.User.current();
+  initialize(container) {
+    const user = container.lookup('current-user:main'),
+          site = container.lookup('site:main'),
+          siteSettings = container.lookup('site-settings:main'),
+          bus = container.lookup('message-bus:main');
 
-    var site = container.lookup('site:main'),
-        siteSettings = container.lookup('site-settings:main');
-
-    var bus = Discourse.MessageBus;
     bus.callbackInterval = siteSettings.anon_polling_interval;
     bus.backgroundCallbackInterval = siteSettings.background_polling_interval;
     bus.baseUrl = siteSettings.long_polling_base_url;
@@ -36,8 +33,8 @@ export default {
         });
       }
       bus.subscribe("/notification/" + user.get('id'), (function(data) {
-        var oldUnread = user.get('unread_notifications');
-        var oldPM = user.get('unread_private_messages');
+        const oldUnread = user.get('unread_notifications');
+        const oldPM = user.get('unread_private_messages');
 
         user.set('unread_notifications', data.unread_notifications);
         user.set('unread_private_messages', data.unread_private_messages);

app/assets/javascripts/discourse/lib/message_bus.js

@@ -1 +0,0 @@
-Discourse.MessageBus = window.MessageBus;

app/assets/javascripts/discourse/models/topic-tracking-state.js.es6

@@ -52,11 +52,10 @@ const TopicTrackingState = Discourse.Model.extend({
       }
     };
 
-    Discourse.MessageBus.subscribe("/new", process);
-    Discourse.MessageBus.subscribe("/latest", process);
-    const currentUser = Discourse.User.current();
-    if(currentUser) {
-      Discourse.MessageBus.subscribe("/unread/" + currentUser.id, process);
+    this.messageBus.subscribe("/new", process);
+    this.messageBus.subscribe("/latest", process);
+    if (this.currentUser) {
+      this.messageBus.subscribe("/unread/" + this.currentUser.get('id'), process);
     }
   },
 
@@ -293,8 +292,14 @@ const TopicTrackingState = Discourse.Model.extend({
 
 
 TopicTrackingState.reopenClass({
-  createFromStates(data){
-    const instance = Discourse.TopicTrackingState.create();
+  createFromStates(data) {
+
+    // TODO: This should be a model that does injection automatically
+    const container = Discourse.__container__,
+          messageBus = container.lookup('message-bus:main'),
+          currentUser = container.lookup('current-user:main'),
+          instance = Discourse.TopicTrackingState.create({ messageBus, currentUser });
+
     instance.loadStates(data);
     instance.establishChannels();
     return instance;

app/assets/javascripts/discourse/routes/user.js.es6

@@ -69,14 +69,14 @@ export default Discourse.Route.extend({
   activate: function() {
     this._super();
     var user = this.modelFor('user');
-    Discourse.MessageBus.subscribe("/users/" + user.get('username_lower'), function(data) {
+    this.messageBus.subscribe("/users/" + user.get('username_lower'), function(data) {
       user.loadUserAction(data);
     });
   },
 
   deactivate: function() {
     this._super();
-    Discourse.MessageBus.unsubscribe("/users/" + this.modelFor('user').get('username_lower'));
+    this.messageBus.unsubscribe("/users/" + this.modelFor('user').get('username_lower'));
 
     // Remove the search context
     this.controllerFor('search').set('searchContext', null);

test/javascripts/test_helper.js

@@ -62,7 +62,7 @@ sinon.config = {
 window.assetPath = function() { return null; };
 
 // Stop the message bus so we don't get ajax calls
-Discourse.MessageBus.stop();
+window.MessageBus.stop();
 
 // Trick JSHint into allow document.write
 var d = document;