make Turnitin::Client#id shard aware

refs CNVS-17473
fixes CNVS-21075

Test plan:
  turnitin still works

Change-Id: I36c34b2a4be67e4d0348dba2de43880ce4a8520a
Reviewed-on: https://gerrit.instructure.com/56782
Reviewed-by: Josh Simpson <jsimpson@instructure.com>
Tested-by: Jenkins
QA-Review: Jason Carter <jcarter@instructure.com>
Product-Review: Cameron Matheson <cameron@instructure.com>

app/models/assignment.rb

@@ -32,6 +32,7 @@ class Assignment < ActiveRecord::Base
   include DatesOverridable
   include SearchTermHelper
   include Canvas::DraftStateValidations
+  include TurnitinID
 
   attr_accessible :title, :name, :description, :due_at, :points_possible,
     :grading_type, :submission_types, :assignment_group, :unlock_at, :lock_at,

app/models/course.rb

@@ -26,6 +26,7 @@ class Course < ActiveRecord::Base
   include HtmlTextHelper
   include TimeZoneHelper
   include ContentLicenses
+  include TurnitinID
 
   attr_accessor :teacher_names
   attr_writer :student_count, :primary_enrollment_type, :primary_enrollment_role_id, :primary_enrollment_rank, :primary_enrollment_state, :invitation
@@ -1792,14 +1793,6 @@ class Course < ActiveRecord::Base
     !!self.turnitin_settings
   end
 
-  def generate_turnitin_id!
-    # the reason we don't just use the global_id all the time is so that the
-    # turnitin_id is preserved when shard splits/etc. occur
-    unless turnitin_id
-      update_attribute(:turnitin_id, global_id)
-    end
-  end
-
   def self.migrate_content_links(html, from_context, to_context, supported_types=nil, user_to_check_for_permission=nil)
     return html unless html.present? && to_context
 

app/models/user.rb

@@ -19,6 +19,8 @@
 require 'atom'
 
 class User < ActiveRecord::Base
+  include TurnitinID
+
   # this has to be before include Context to prevent a circular dependency in Course
   def self.sortable_name_order_by_clause(table = nil)
     col = table ? "#{table}.sortable_name" : 'sortable_name'

db/migrate/20150618183919_needs_more_turnitin_id.rb

@@ -0,0 +1,8 @@
+class NeedsMoreTurnitinId < ActiveRecord::Migration
+  tag :predeploy
+
+  def change
+    add_column :assignments, :turnitin_id, :integer, limit: 8, unique: :true
+    add_column :users, :turnitin_id, :integer, limit: 8, unique: :true
+  end
+end

lib/turnitin.rb

@@ -62,6 +62,8 @@ module Turnitin
     def id(obj)
       if @testing
         "test_#{obj.asset_string}"
+      elsif obj.respond_to?(:turnitin_id)
+        obj.turnitin_asset_string
       else
         "#{account_id}_#{obj.asset_string}"
       end
@@ -72,9 +74,7 @@ module Turnitin
       email = if item.is_a?(User)
                 item.email
               elsif item.respond_to?(:turnitin_id)
-                item.generate_turnitin_id!
-                item_type = item.class.reflection_type_name
-                "#{item_type}_#{item.turnitin_id}@null.instructure.example.com"
+                "#{item.turnitin_asset_string}@null.instructure.example.com"
               end
       email ||= "#{item.asset_string}@null.instructure.example.com"
     end

lib/turnitin_id.rb

@@ -0,0 +1,12 @@
+module TurnitinID
+  def generate_turnitin_id!
+    # the reason we don't just use the global_id all the time is so that the
+    # turnitin_id is preserved when shard splits/etc. occur
+    turnitin_id || update_attribute(:turnitin_id, global_id)
+  end
+
+  def turnitin_asset_string
+    generate_turnitin_id!
+    "#{self.class.reflection_type_name}_#{turnitin_id}"
+  end
+end

spec/lib/turnitin_spec.rb

@@ -350,4 +350,16 @@ describe Turnitin::Client do
       expect(@course.turnitin_id).to eql @course.global_id
     end
   end
+
+  describe '#id' do
+    it "uses turnitin_id when defined" do
+      turnitin = Turnitin::Client.new('blah', 'blah')
+      student_in_course active_all: true
+      assignment = @course.assignments.create!
+
+      expect(turnitin.id(@course)).to eql "course_#{@course.turnitin_id}"
+      expect(turnitin.id(assignment)).to eql "assignment_#{assignment.turnitin_id}"
+      expect(turnitin.id(@student)).to eql "user_#{@student.turnitin_id}"
+    end
+  end
 end