DEV: Add push notification filtering to MessageBus alerts (#25965)

plugins/chat/app/jobs/regular/chat/notify_watching.rb

@@ -76,7 +76,17 @@ module Jobs
         }
 
         if membership.desktop_notifications_always? && !membership.muted?
-          ::MessageBus.publish("/chat/notification-alert/#{user.id}", payload, user_ids: [user.id])
+          send_notification =
+            DiscoursePluginRegistry.push_notification_filters.all? do |filter|
+              filter.call(user, payload)
+            end
+          if send_notification
+            ::MessageBus.publish(
+              "/chat/notification-alert/#{user.id}",
+              payload,
+              user_ids: [user.id],
+            )
+          end
         end
 
         if membership.mobile_notifications_always? && !membership.muted?

plugins/chat/spec/jobs/regular/chat/notify_watching_spec.rb

@@ -85,6 +85,16 @@ RSpec.describe Jobs::Chat::NotifyWatching do
       end
     end
 
+    context "with push_notification_filter registered to block push notifications" do
+      after { DiscoursePluginRegistry.reset_register!(:push_notification_filters) }
+
+      it "doesn't send notification alert via MessageBus" do
+        Plugin::Instance.new.register_push_notification_filter { |user, payload| false }
+
+        expect(notification_messages_for(user2)).to be_empty
+      end
+    end
+
     context "when the channel is muted via membership preferences" do
       before { membership2.update!(muted: true) }