Fix user avatar stale cache issues with MR sidebar_extras

app/controllers/projects/merge_requests_controller.rb

@@ -131,9 +131,16 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
         Gitlab::PollingInterval.set_header(response, interval: 10_000)
 
         if params[:serializer] == 'sidebar_extras' && Feature.enabled?(:merge_request_show_render_cached, @project, default_enabled: :yaml)
+          cache_context = [
+            params[:serializer],
+            current_user&.cache_key,
+            @merge_request.assignees.map(&:cache_key),
+            @merge_request.reviewers.map(&:cache_key)
+          ]
+
           render_cached(@merge_request,
                         with: serializer,
-                        cache_context: -> (_) { [params[:serializer], current_user&.cache_key, project.emails_disabled?, issuable.subscribed?(current_user, project)] },
+                        cache_context: -> (_) { [Digest::SHA256.hexdigest(cache_context.to_s)] },
                         serializer: params[:serializer])
         else
           render json: serializer.represent(@merge_request, serializer: params[:serializer])

spec/requests/projects/merge_requests_spec.rb

@@ -5,10 +5,18 @@ require 'spec_helper'
 RSpec.describe 'merge requests actions' do
   let_it_be(:project) { create(:project, :repository) }
 
-  let(:merge_request) { create(:merge_request_with_diffs, target_project: project, source_project: project) }
+  let(:merge_request) do
+    create(:merge_request_with_diffs, target_project: project,
+                                      source_project: project,
+                                      assignees: [user],
+                                      reviewers: [user2])
+  end
+
   let(:user) { project.owner }
+  let(:user2) { create(:user) }
 
   before do
+    project.add_maintainer(user2)
     sign_in(user)
   end
 
@@ -61,17 +69,11 @@ RSpec.describe 'merge requests actions' do
             end
 
             context 'when the merge request is updated' do
-              let(:user2) { create(:user) }
-
-              before do
-                project.add_maintainer(user2)
-              end
-
               def update_service(params)
                 MergeRequests::UpdateService.new(project: project, current_user: user, params: params).execute(merge_request)
               end
 
-              context 'when the user is different' do
+              context 'when the logged in user is different' do
                 before do
                   sign_in(user2)
                 end
@@ -79,61 +81,61 @@ RSpec.describe 'merge requests actions' do
                 it_behaves_like 'a non-cached request'
               end
 
-              context 'when the reviewer is changed' do
+              context 'when the assignee is changed' do
                 before do
-                  update_service(reviewer_ids: [user2.id])
+                  update_service( assignee_ids: [] )
                 end
 
                 it_behaves_like 'a non-cached request'
               end
 
-              context 'when the assignee is changed' do
+              context 'when the existing assignee gets updated' do
                 before do
-                  update_service( assignee_ids: [user2.id] )
+                  user.update_attribute(:avatar, 'uploads/avatar.png')
                 end
 
                 it_behaves_like 'a non-cached request'
               end
 
-              context 'when the time_estimate is changed' do
+              context 'when the reviewer is changed' do
                 before do
-                  update_service(time_estimate: 7200)
+                  update_service(reviewer_ids: [])
                 end
 
                 it_behaves_like 'a non-cached request'
               end
 
-              context 'when the spend_time is changed' do
+              context 'when the existing reviewer gets updated' do
                 before do
-                  update_service(spend_time: { duration: 7200, user_id: user.id, spent_at: Time.now, note_id: nil })
+                  user2.update_attribute(:avatar, 'uploads/avatar.png')
                 end
 
                 it_behaves_like 'a non-cached request'
               end
 
-              context 'when a user leaves a note' do
+              context 'when the time_estimate is changed' do
                 before do
-                  # We have 1 minute ThrottledTouch to account for.
-                  # It's not ideal as it means that our participants cache could be stale for about a day if a new note is created by another person or gets a mention.
-                  travel_to(Time.current + 61) do
-                    Notes::CreateService.new(project, user2, { note: 'Looks good', noteable_type: 'MergeRequest', noteable_id: merge_request.id }).execute
-                  end
+                  update_service(time_estimate: 7200)
                 end
 
                 it_behaves_like 'a non-cached request'
               end
 
-              context 'when the email setting has changed in project' do
+              context 'when the spend_time is changed' do
                 before do
-                  project.namespace.update_attribute(:emails_disabled, true)
+                  update_service(spend_time: { duration: 7200, user_id: user.id, spent_at: Time.now, note_id: nil })
                 end
 
                 it_behaves_like 'a non-cached request'
               end
 
-              context 'when the user changes unsubscribes' do
+              context 'when a user leaves a note' do
                 before do
-                  merge_request.set_subscription(user, false, project)
+                  # We have 1 minute ThrottledTouch to account for.
+                  # It's not ideal as it means that our participants cache could be stale for about a day if a new note is created by another person or gets a mention.
+                  travel_to(Time.current + 61) do
+                    Notes::CreateService.new(project, user2, { note: 'Looks good', noteable_type: 'MergeRequest', noteable_id: merge_request.id }).execute
+                  end
                 end
 
                 it_behaves_like 'a non-cached request'