Enqueue PushNotification background job on Post persistence

app/services/persister/post_persister.rb

@@ -10,6 +10,7 @@ def save
       ::ActiveRecord::Base.transaction do
         post.save!
         create_save_event!
+        enqueue_push_notification_job!
         post
       end
     rescue ActiveRecord::RecordInvalid => _exception
@@ -20,6 +21,7 @@ def update_attributes(params)
       ::ActiveRecord::Base.transaction do
         post.update_attributes!(params)
         create_update_event!
+        enqueue_push_notification_job!
         post
       end
     rescue ActiveRecord::RecordInvalid => _exception
@@ -28,12 +30,18 @@ def update_attributes(params)
 
     private
 
+    attr_accessor :event
+
     def create_save_event!
-      ::Event.create! action: :created, post: post
+      @event = ::Event.create! action: :created, post: post
     end
 
     def create_update_event!
-      ::Event.create! action: :updated, post: post
+      @event = ::Event.create! action: :updated, post: post
+    end
+
+    def enqueue_push_notification_job!
+      CreatePushNotificationsJob.perform_later(event_id: event.id)
     end
   end
 end

spec/services/persister/post_persister_spec.rb

@@ -14,30 +14,57 @@
     )
   end
   let(:persister) { ::Persister::PostPersister.new(post) }
+  let(:event) { Fabricate.build(:event, id: 27) }
 
   describe '#save' do
-    before { persister.save }
-
     it 'saves the post' do
+      persister.save
+
       expect(post).to be_persisted
     end
 
-    # TODO: write better expectation
     it 'creates an event' do
-      expect(Event.where(post_id: post.id).first.action).to eq('created')
+      expect(::Event).to receive(:create!).with(action: :created, post: post).and_return(event)
+
+      persister.save
+    end
+
+    context 'background job' do
+      before do
+        ActiveJob::Base.queue_adapter = :test
+        allow(::Event).to receive(:create!).and_return(event)
+        persister.save
+      end
+
+      it 'enqueues a CreatePushNotificationsJob background job' do
+        expect(CreatePushNotificationsJob).to have_been_enqueued.with(event_id: 27)
+      end
     end
   end
 
   describe '#update_attributes' do
-    before { persister.update_attributes(title: 'New title') }
-
     it 'updates the resource attributes' do
+      persister.update_attributes(title: 'New title')
+
       expect(post.title).to eq('New title')
     end
 
-    # TODO: write better expectation
     it 'creates an event' do
-      expect(Event.where(post_id: post.id).first.action).to eq('updated')
+      expect(::Event).to receive(:create!).with(action: :updated, post: post).and_return(event)
+
+      persister.update_attributes(title: 'New title')
+    end
+
+    context 'background job' do
+      before do
+        ActiveJob::Base.queue_adapter = :test
+        allow(::Event).to receive(:create!).and_return(event)
+        persister.update_attributes(title: 'New title')
+      end
+
+      it 'enqueues a CreatePushNotificationsJob background job' do
+        expect(CreatePushNotificationsJob).to have_been_enqueued.with(event_id: 27)
+      end
     end
   end
 end