FIX: DiscourseEvent should not be triggered from within the controller.

app/controllers/topics_controller.rb

@@ -342,8 +342,6 @@ class TopicsController < ApplicationController
     first_post = topic.ordered_posts.first
     PostDestroyer.new(current_user, first_post, { context: params[:context] }).destroy
 
-    DiscourseEvent.trigger(:topic_destroyed, topic, current_user)
-
     render nothing: true
   end
 
@@ -354,8 +352,6 @@ class TopicsController < ApplicationController
     first_post = topic.posts.with_deleted.order(:post_number).first
     PostDestroyer.new(current_user, first_post).recover
 
-    DiscourseEvent.trigger(:topic_recovered, topic, current_user)
-
     render nothing: true
   end
 

lib/post_destroyer.rb

@@ -47,6 +47,7 @@ class PostDestroyer
       mark_for_deletion
     end
     DiscourseEvent.trigger(:post_destroyed, @post, @opts, @user)
+    DiscourseEvent.trigger(:topic_destroyed, @topic, @user) if @post.is_first_post?
   end
 
   def recover
@@ -60,6 +61,7 @@ class PostDestroyer
     topic.update_statistics
     recover_user_actions
     DiscourseEvent.trigger(:post_recovered, @post, @opts, @user)
+    DiscourseEvent.trigger(:topic_recovered, topic, @user) if @post.is_first_post?
   end
 
   def staff_recovered

spec/components/post_destroyer_spec.rb

@@ -193,10 +193,19 @@ describe PostDestroyer do
   end
 
   describe 'basic destroying' do
-
     it "as the creator of the post, doesn't delete the post" do
+      begin
         post2 = create_post
 
+        called = 0
+        topic_destroyed = -> (topic, user) do
+          expect(topic).to eq(post2.topic)
+          expect(user).to eq(post2.user)
+          called += 1
+        end
+
+        DiscourseEvent.on(:topic_destroyed, &topic_destroyed)
+
         @orig = post2.cooked
         PostDestroyer.new(post2.user, post2).destroy
         post2.reload
@@ -206,6 +215,16 @@ describe PostDestroyer do
         expect(post2.user_deleted).to eq(true)
         expect(post2.raw).to eq(I18n.t('js.post.deleted_by_author', {count: 24}))
         expect(post2.version).to eq(2)
+        expect(called).to eq(1)
+
+        called = 0
+        topic_recovered = -> (topic, user) do
+          expect(topic).to eq(post2.topic)
+          expect(user).to eq(post2.user)
+          called += 1
+        end
+
+        DiscourseEvent.on(:topic_recovered, &topic_recovered)
 
         # lets try to recover
         PostDestroyer.new(post2.user, post2).recover
@@ -213,7 +232,11 @@ describe PostDestroyer do
         expect(post2.version).to eq(3)
         expect(post2.user_deleted).to eq(false)
         expect(post2.cooked).to eq(@orig)
-
+        expect(called).to eq(1)
+      ensure
+        DiscourseEvent.off(:topic_destroyed, &topic_destroyed)
+        DiscourseEvent.off(:topic_recovered, &topic_recovered)
+      end
     end
 
     context "as a moderator" do