Add conversation message created live event

refs PFS-15497
flag = none

Test plan:
1. create a new conversation on canvas with another user
2. create a new message in the conversation by replying
3. verify live event for conversation_message_created has been triggered

Change-Id: Idf929eb5398f6040d8a3e45c644481b207858042
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/232152
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
Product-Review: Dan Dickson <ddickson@instructure.com>
QA-Review: Aiona Rae Hernandez <ahernandez@instructure.com>
Reviewed-by: Sean Mikkelsen <smikkelsen@instructure.com>
Reviewed-by: Weston Dransfield <wdransfield@instructure.com>

app/observers/live_events_observer.rb

@@ -19,6 +19,7 @@ class LiveEventsObserver < ActiveRecord::Observer
   observe :content_export,
           :content_migration,
           :conversation,
+          :conversation_message,
           :course,
           :discussion_entry,
           :discussion_topic,

lib/canvas/live_events.rb

@@ -88,6 +88,15 @@ module Canvas::LiveEvents
     })
   end
 
+  def self.conversation_message_created(conversation_message)
+    post_event_stringified('conversation_message_created', {
+      author_id: conversation_message.author_id,
+      conversation_id: conversation_message.conversation_id,
+      created_at: conversation_message.created_at,
+      message_id: conversation_message.id
+    })
+  end
+
   def self.discussion_entry_created(entry)
     post_event_stringified('discussion_entry_created', get_discussion_entry_data(entry))
   end

lib/canvas/live_events_callbacks.rb

@@ -24,6 +24,8 @@ module Canvas::LiveEventsCallbacks
       Canvas::LiveEvents.course_created(obj)
     when Conversation
       Canvas::LiveEvents.conversation_created(obj)
+    when ConversationMessage
+      Canvas::LiveEvents.conversation_message_created(obj)
     when DiscussionEntry
       Canvas::LiveEvents.discussion_entry_created(obj)
     when DiscussionTopic

spec/lib/canvas/live_events_spec.rb

@@ -271,6 +271,22 @@ describe Canvas::LiveEvents do
     end
   end
 
+  describe ".conversation_message_created" do
+    it "should include the author id, conversation message id, and conversation id" do
+      user1 = user_model
+      user2 = user_model
+      convo = Conversation.initiate([user1, user2], false)
+      convo_message = convo.add_message(user1, 'Hi! You are doing great...')
+      expect_event('conversation_message_created',
+        hash_including(
+          author_id: convo_message.author_id.to_s,
+          conversation_id: convo_message.conversation_id.to_s,
+          message_id: convo_message.id.to_s
+        )).once
+      Canvas::LiveEvents.conversation_message_created(convo_message)
+    end
+  end
+
   describe '.course_grade_change' do
     before(:once) do
       @user = User.create!

spec/observers/live_events_observer_spec.rb

@@ -115,6 +115,16 @@ describe LiveEventsObserver do
   end
 
 
+  describe "conversation messsage" do
+    it "posts conversation message create events" do
+      expect(Canvas::LiveEvents).to receive(:conversation_message_created).once
+      user1 = user_model
+      user2 = user_model
+      convo = Conversation.initiate([user1, user2], false)
+      convo.add_message(user1, "create new conversation message")
+    end
+  end
+
   describe "course" do
     it "posts create events" do
       expect(Canvas::LiveEvents).to receive(:course_created).once