hide blueprint lock icons on child courses

A front-end performance hack on courses with large numbers of modules.
If this feature flag is on we hide the lock icons on child courses and
instead append a lock emoji to the title when there are restrictions.
This is a performance hack that should be sparingly used.

flag=modules_page_hide_blueprint_lock_icon_for_children

test plan:
  - turn on the feature flag
  - Create a blueprint parent course with an assignment that has some
    restrictions
  - Create a child course from the blueprint
  - Go to the modules page in the child course and verify that the lock
    icon is not added via javascript (on the right side of the page) but
    is an emoji added from the ERB near the title

Change-Id: I968d92396d0b099d121f71360a1ea97c3dd4c9cf
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/356281
Reviewed-by: Spencer Olson <solson@instructure.com>
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
QA-Review: Keith Garner <kgarner@instructure.com>
Product-Review: Keith Garner <kgarner@instructure.com>

app/controllers/context_modules_controller.rb

@@ -145,14 +145,18 @@ class ContextModulesController < ApplicationController
       }
 
       is_master_course = MasterCourses::MasterTemplate.is_master_course?(@context)
-      is_child_course = MasterCourses::ChildSubscription.is_child_course?(@context)
+      @is_child_course = MasterCourses::ChildSubscription.is_child_course?(@context)
-      if is_master_course || is_child_course
+      if is_master_course || @is_child_course
         hash[:MASTER_COURSE_SETTINGS] = {
           IS_MASTER_COURSE: is_master_course,
-          IS_CHILD_COURSE: is_child_course,
+          IS_CHILD_COURSE: @is_child_course,
           MASTER_COURSE_DATA_URL: context_url(@context, :context_context_modules_master_course_info_url)
         }
       end
+      if !@is_student && @is_child_course &&
+         @context.account.feature_enabled?(:modules_page_hide_blueprint_lock_icon_for_children)
+        hash[:HIDE_BLUEPRINT_LOCK_ICON_FOR_CHILDREN] = true
+      end
 
       append_default_due_time_js_env(@context, hash)
       js_env(hash)

app/helpers/context_modules_helper.rb

@@ -154,6 +154,13 @@ module ContextModulesHelper
     end
 
     module_data[:items_data] = items_data
+
+    if @is_child_course && !is_student &&
+       @context.account.feature_enabled?(:modules_page_hide_blueprint_lock_icon_for_children)
+      module_data[:items_restrictions] =
+        MasterCourses::MasterContentTag.fetch_module_item_restrictions_for_child(module_data[:items].map(&:id))
+      module_data[:items_restrictions].transform_values!(&:any?)
+    end
     module_data
   end
 

app/views/context_modules/_context_module_next.html.erb

@@ -241,9 +241,10 @@
           <%
             item_data = module_data[:items_data][item.id]
             locals = {
-              :completion_criteria => context_module.completion_requirements,
+              item_restrictions: module_data.dig(:items_restrictions, item.id),
-              :item_data => item_data,
+              completion_criteria: context_module.completion_requirements,
-              :viewable => @can_view,
+              item_data: item_data,
+              viewable: @can_view,
             }
           %>
           <%= render :partial => 'context_modules/module_item_next', :object => item, :as => :module_item, :locals => locals %>

app/views/context_modules/_module_item_next.html.erb

@@ -24,6 +24,7 @@
   can_direct_share = can_do(@context, @current_user, :direct_share)
   criterion = completion_criteria && completion_criteria.find{|c| c[:id] == module_item.id}
   show_checkpoints = @context.root_account.feature_enabled?(:discussion_checkpoints) && module_item && module_item.content_type == 'DiscussionTopic' && module_item.content.checkpoints?
+  item_restrictions ||= nil
 
   @module_item_image_tags ||= {
     'indent' => "<i class='icon-arrow-right'></i>".html_safe,
@@ -101,30 +102,35 @@
     <div class="ig-info">
       <div class="module-item-title">
         <span class="item_name">
+          <% title = module_item&.title %>
           <% if module_item && module_item.content_type == 'ExternalUrl' && module_item.new_tab %>
             <% # FYI, this link gets opened via context_modules_helper.externalUrlLinkClick %>
             <a
-              title="<%= module_item && module_item.title %>"
+              title="<%= title %>"
               class="title external_url_link"
               target="_blank"
               href="<%= module_item.url %>"
               data-item-href="<%= context_url(@context, :context_url) %>/modules/items/<%= module_item.id %>"
             >
-              <%= module_item.title %>
+              <%= title %>
             </a>
           <% elsif !(module_item && module_item.content_type == 'ContextModuleSubHeader') %>
             <a
-              title="<%= module_item && module_item.title %>"
+              title="<%= title %>"
               class="ig-title title item_link"
               href="<%= context_url(@context, :context_url) %>/modules/items/<%= module_item ? module_item.id : "{{ id }}" %>"
               <% if item_data[:mastery_paths] && item_data[:mastery_paths][:locked] %>
               aria-describedby="module-item-locked-<%= module_item && module_item.id %>"
               <% end %>
             >
-              <%= module_item && module_item.title %>
+              <%= title %>
             </a>
+            <% if title && item_restrictions %>
+              🔒
             <% end %>
-          <span title="<%= module_item && module_item.title %>" class="title locked_title"><%= module_item && module_item.title %></span>
+          <% end %>
+
+          <span title="<%= title %>" class="title locked_title"><%= title %></span>
           <span class="points_possible" style="display: none;"><%= round_if_whole(module_item.try_rescue(:assignment).try_rescue(:points_possible)) || nbsp %></span>
           <span class="requirement" style="display: none;">&nbsp;</span>
           <span class="completion_requirement" style="display: none;">&nbsp;</span>

config/feature_flags/learning_foundations_release_flags.yml

@@ -215,3 +215,12 @@ dashboard_graphql_integration:
     Integrate GraphQL queries and mutations for the Dashboard to improve loading speed
     and simplify data fetching logic.
   applies_to: SiteAdmin
+
+modules_page_hide_blueprint_lock_icon_for_children:
+  state: hidden
+  display_name: Hide Blueprint Lock Icon on child course Modules Page
+  description: |-
+    If enabled, the blueprint lock icon will be hidden on the modules page. This is a performance hack and should only
+    be used for customers with a large number of content items (2000+) in a course.
+  applies_to: Account
+

spec/helpers/context_modules_helper_spec.rb

@@ -253,6 +253,51 @@ describe ContextModulesHelper do
 
       expect(module_data[:items]).to be_empty
     end
+
+    context "feature flag modules_page_hide_blueprint_lock_icon_for_children" do
+      context "is on" do
+        before(:once) do
+          t_course.account.feature_flags.create!(feature: "modules_page_hide_blueprint_lock_icon_for_children", state: "on")
+        end
+
+        it "returns blueprinit item restrictions for a teacher in a child course" do
+          @is_child_course = true
+          module_data = process_module_data(t_module, false, @teacher, @session)
+
+          expect(module_data[:items_restrictions]).not_to be_nil
+        end
+
+        it "does not return blueprinit item restrictions for a student in a child course" do
+          @is_child_course = true
+          module_data = process_module_data(t_module, true, @student, @session)
+
+          expect(module_data[:items_restrictions]).to be_nil
+        end
+
+        it "does not return blueprinit item restrictions for a teacher if not a blueprint child" do
+          @is_child_course = nil
+          module_data = process_module_data(t_module, false, @teacher, @session)
+
+          expect(module_data[:items_restrictions]).to be_nil
+        end
+      end
+
+      context "is off" do
+        it "does not return blueprinit item restrictions for a teacher in a child course" do
+          @is_child_course = true
+          module_data = process_module_data(t_module, false, @teacher, @session)
+
+          expect(module_data[:items_restrictions]).to be_nil
+        end
+
+        it "does not return blueprinit item restrictions for a student in a child course" do
+          @is_child_course = true
+          module_data = process_module_data(t_module, true, @student, @session)
+
+          expect(module_data[:items_restrictions]).to be_nil
+        end
+      end
+    end
   end
 
   describe "add_mastery_paths_to_cache_key" do

ui/shared/context-modules/jquery/index.jsx

@@ -369,8 +369,15 @@ window.modules = (function () {
                   item.setAttribute('data-master_course_restrictions', JSON.stringify(restriction))
                 }
 
+                if (
+                  !(
+                    ENV.MASTER_COURSE_SETTINGS.IS_CHILD_COURSE &&
+                    ENV.HIDE_BLUEPRINT_LOCK_ICON_FOR_CHILDREN
+                  )
+                ) {
                   this.initMasterCourseLockButton(item, restriction)
                 }
+              }
             })
           }
         })