add api flag to not send notifications for content exports

Test Plan:
 * Create a ContentExport through the api setting the skip_notifications to false
 * When it finishes you shouldn't get an email

closes PLAT-591

Change-Id: I036c65012bec6fe7cb57f6b79b3684c3b9eadf3f
Reviewed-on: https://gerrit.instructure.com/39015
QA-Review: Clare Strong <clare@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Jeremy Stanley <jeremy@instructure.com>
Product-Review: Bracken Mosbacker <bracken@instructure.com>

app/controllers/content_exports_api_controller.rb

@@ -126,6 +126,9 @@ class ContentExportsApiController < ApplicationController
   #   "qti":: Export quizzes from a course in the QTI format
   #   "zip":: Export files from a course, group, or user in a zip file
   #
+  # @argument skip_notifications [Optional, Boolean]
+  #   Don't send the notifications about the export to the user. Default: false
+  #
   # @returns ContentExport
   def create
     if authorized_action(@context, @current_user, :read)
@@ -135,6 +138,7 @@ class ContentExportsApiController < ApplicationController
       export = @context.content_exports.build
       export.user = @current_user
       export.workflow_state = 'created'
+      export.settings[:skip_notifications] = true if value_to_boolean(params[:skip_notifications])
 
       # ZipExporter accepts unhashed asset strings, to avoid having to instantiate all the files and folders
       selected_content = ContentMigration.process_copy_params(params[:select], true, params[:export_type] == ContentExport::ZIP) if params[:select]

app/models/content_export.rb

@@ -48,17 +48,24 @@ class ContentExport < ActiveRecord::Base
     state :deleted
   end
 
+  def send_notification?
+    context_type == 'Course' &&
+            export_type != ZIP &&
+            content_migration.blank? &&
+            !settings[:skip_notifications]
+  end
+
   set_broadcast_policy do |p|
     p.dispatch :content_export_finished
     p.to { [user] }
     p.whenever {|record|
-      record.context_type == 'Course' && record.export_type != ZIP && record.changed_state(:exported) && self.content_migration.blank?
+      record.changed_state(:exported) && record.send_notification?
     }
     
     p.dispatch :content_export_failed
     p.to { [user] }
     p.whenever {|record|
-      record.context_type == 'Course' && record.export_type != ZIP && record.changed_state(:failed) && self.content_migration.blank?
+      record.changed_state(:failed) && record.send_notification?
     }
   end
 

spec/apis/v1/content_exports_api_spec.rb

@@ -173,6 +173,13 @@ describe ContentExportsApiController, type: :request do
         {}, {}, { expected_status: 400 })
     end
 
+    it "should set skip notifications flag" do
+      json = api_call_as_user(t_teacher, :post, "/api/v1/courses/#{t_course.id}/content_exports",
+        { controller: 'content_exports_api', action: 'create', format: 'json', course_id: t_course.to_param, export_type: 'common_cartridge', skip_notifications: true })
+      export = t_course.content_exports.find_by_id(json['id'])
+      export.send_notification?.should be_false
+    end
+
     it "should create a qti export" do
       json = api_call_as_user(t_teacher, :post, "/api/v1/courses/#{t_course.id}/content_exports?export_type=qti",
         { controller: 'content_exports_api', action: 'create', format: 'json', course_id: t_course.to_param, export_type: 'qti' })