DEV: Replace `message-bus:main` with `service:message-bus` (#17691)

This will allow consumers to inject it using `messageBus: service()` in preparation for the removal of implicit injections in Ember 4.0. `message-bus:main` is still available and will print a deprecation notice.

The MessageBus library is not en ember object, and doesn't need access to any of our injections. Therefore, we can set up a simple class which defines itself as a 'Service Factory', and returns the MessageBus library in the `create` method.

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

@@ -11,7 +11,7 @@ export default {
 
     site.set("banner", banner);
 
-    const messageBus = container.lookup("message-bus:main");
+    const messageBus = container.lookup("service:message-bus");
     if (!messageBus) {
       return;
     }

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

@@ -7,7 +7,7 @@ export default {
   name: "live-development",
 
   initialize(container) {
-    const messageBus = container.lookup("message-bus:main");
+    const messageBus = container.lookup("service:message-bus");
     const session = container.lookup("session:main");
 
     // Preserve preview_theme_id=## and pp=async-flamegraph parameters across pages

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

@@ -10,7 +10,7 @@ export default {
   after: "message-bus",
 
   initialize(container) {
-    const messageBus = container.lookup("message-bus:main");
+    const messageBus = container.lookup("service:message-bus");
 
     if (!messageBus) {
       return;

app/assets/javascripts/discourse/app/initializers/logs-notice.js

@@ -12,7 +12,7 @@ export default {
     }
 
     const siteSettings = container.lookup("site-settings:main");
-    const messageBus = container.lookup("message-bus:main");
+    const messageBus = container.lookup("service:message-bus");
     const keyValueStore = container.lookup("service:key-value-store");
     const currentUser = container.lookup("current-user:main");
     LogsNotice.reopenClass(Singleton, {

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

@@ -40,7 +40,7 @@ export default {
       return;
     }
 
-    const messageBus = container.lookup("message-bus:main"),
+    const messageBus = container.lookup("service:message-bus"),
       user = container.lookup("current-user:main"),
       siteSettings = container.lookup("site-settings:main");
 

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

@@ -4,7 +4,7 @@ export default {
   after: "message-bus",
 
   initialize(container) {
-    const messageBus = container.lookup("message-bus:main");
+    const messageBus = container.lookup("service:message-bus");
     if (!messageBus) {
       return;
     }

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

@@ -20,7 +20,7 @@ export default {
 
   initialize(container) {
     const user = container.lookup("current-user:main");
-    const bus = container.lookup("message-bus:main");
+    const bus = container.lookup("service:message-bus");
     const appEvents = container.lookup("service:app-events");
 
     if (user) {

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

@@ -2,7 +2,6 @@ import TopicTrackingState, {
   startTracking,
 } from "discourse/models/topic-tracking-state";
 import DiscourseLocation from "discourse/lib/discourse-location";
-import MessageBus from "message-bus-client";
 import Session from "discourse/models/session";
 import Site from "discourse/models/site";
 import User from "discourse/models/user";
@@ -17,9 +16,6 @@ export function registerObjects(app) {
   }
   app.__registeredObjects__ = true;
 
-  // TODO: This should be included properly
-  app.register("message-bus:main", MessageBus, { instantiate: false });
-
   const siteSettings = app.SiteSettings;
   app.register("site-settings:main", siteSettings, { instantiate: false });
 }
@@ -98,6 +94,15 @@ export default {
       dropFrom: "3.0.0",
     });
 
+    deprecateRegistration({
+      app,
+      container,
+      oldName: "message-bus:main",
+      newName: "service:message-bus",
+      since: "2.9.0.beta7",
+      dropFrom: "3.0.0",
+    });
+
     let siteSettings = container.lookup("site-settings:main");
 
     const currentUser = User.current();
@@ -105,7 +110,7 @@ export default {
     app.currentUser = currentUser;
 
     const topicTrackingState = TopicTrackingState.create({
-      messageBus: MessageBus,
+      messageBus: container.lookup("service:message-bus"),
       siteSettings,
       currentUser,
     });
@@ -129,14 +134,19 @@ export default {
       app.inject(t, "site", "site:main");
       app.inject(t, "searchService", "service:search");
       app.inject(t, "session", "session:main");
-      app.inject(t, "messageBus", "message-bus:main");
+      app.inject(t, "messageBus", "service:message-bus");
       app.inject(t, "siteSettings", "site-settings:main");
       app.inject(t, "topicTrackingState", "topic-tracking-state:main");
       app.inject(t, "keyValueStore", "service:key-value-store");
     });
 
     app.inject("service", "session", "session:main");
-    app.inject("service", "messageBus", "message-bus:main");
+    injectServiceIntoService({
+      container,
+      app,
+      property: "messageBus",
+      specifier: "service:message-bus",
+    });
     app.inject("service", "siteSettings", "site-settings:main");
     app.inject("service", "topicTrackingState", "topic-tracking-state:main");
     injectServiceIntoService({

app/assets/javascripts/discourse/app/services/message-bus.js

@@ -0,0 +1,9 @@
+import MessageBus from "message-bus-client";
+
+export default class MessageBusService {
+  static isServiceFactory = true;
+
+  static create() {
+    return MessageBus;
+  }
+}