Add line_item extensions to line_item json

refs PLAT-4486

Test Plan:
 - create a line_item with the extension defined, should show up
   in the retrieval of that line_item

Change-Id: Ia379329dc3509c4d91b81d6e218afb9add7d9dc7
Reviewed-on: https://gerrit.instructure.com/198547
Tested-by: Jenkins
QA-Review: Marc Phillips <mphillips@instructure.com>
Product-Review: Marc Phillips <mphillips@instructure.com>
Reviewed-by: Weston Dransfield <wdransfield@instructure.com>

app/controllers/lti/ims/line_items_controller.rb

@@ -55,6 +55,11 @@ module Lti
     #            "description": "The resource link id the Line Item is attached to",
     #            "example": "50",
     #            "type": "string"
+    #          },
+    #          "https://canvas.instructure.com/lti/submission_type": {
+    #            "description": "The extension that defines the submission_type of the line_item. Only returns if set through the line_item create endpoint.",
+    #            "example": "{\n\t\"type\":\"external_tool\",\n\t\"external_tool_url\":\"https://my.launch.url\",\n}",
+    #            "type": "string"
     #          }
     #       }
     #     }
@@ -122,6 +127,7 @@ module Lti
       #       "external_tool_url": "https://my.launch.url"
       #     }
       #   }
+      #
       # @returns LineItem
       def create
         new_line_item = LineItem.create_line_item!(

app/models/lti/line_item.rb

@@ -65,8 +65,7 @@ class Lti::LineItem < ApplicationRecord
             url: submission_type[:external_tool_url]
           }
 
-          # remove submission params from line item so it can save correctly
-          params = params.except(AGS_EXT_SUBMISSION_TYPE)
+          params = extract_extensions(params)
         else
           raise ActionController::BadRequest, "Invalid submission_type for new assignment: #{submission_type[:type]}"
         end
@@ -79,6 +78,13 @@ class Lti::LineItem < ApplicationRecord
     end
   end
 
+  def self.extract_extensions(params)
+    hsh = params.to_unsafe_h
+    hsh[:extensions] = { AGS_EXT_SUBMISSION_TYPE => hsh.delete(AGS_EXT_SUBMISSION_TYPE) }
+    hsh
+  end
+  private_class_method :extract_extensions
+
   private
 
   def resource_link_id_has_one_assignment

app/serializers/lti/ims/line_items_serializer.rb

@@ -30,7 +30,7 @@ module Lti::Ims
         resourceId: @line_item.resource_id,
         tag: @line_item.tag,
         resourceLinkId: @line_item.resource_link&.resource_link_id
-      }.compact
+      }.merge(@line_item.extensions).compact
     end
   end
 end

db/migrate/20190620215202_add_lti_line_item_extensions.rb

@@ -0,0 +1,24 @@
+#
+# Copyright (C) 2019 - present Instructure, Inc.
+#
+# This file is part of Canvas.
+#
+# Canvas is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Affero General Public License as published by the Free
+# Software Foundation, version 3 of the License.
+#
+# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along
+# with this program. If not, see <http://www.gnu.org/licenses/>.
+
+class AddLtiLineItemExtensions < ActiveRecord::Migration[5.1]
+  tag :predeploy
+
+  def change
+    add_column :lti_line_items, :extensions, :jsonb, default: {}
+  end
+end

spec/controllers/lti/ims/line_items_controller_spec.rb

@@ -253,9 +253,14 @@ module Lti
               it 'sets the assignment submission type to external tool' do
                 expect(item.assignment.submission_types).to eq 'external_tool'
               end
+
               it 'sets the assignment external url' do
                 expect(item.assignment.external_tool_tag.url).to eq "http://www.google.com"
               end
+
+              it 'sets the extension on return' do
+                expect(json[LineItem::AGS_EXT_SUBMISSION_TYPE][:external_tool_url]).to eq "http://www.google.com"
+              end
             end
 
             context 'when submission type is invalid' do
@@ -663,16 +668,25 @@ module Lti
           end
         end
 
-        xcontext 'when using the uncoupled model' do
+        context 'when using the uncoupled model' do
           let(:line_item) do
             line_item_model(
               course: course,
               tag: tag,
-              resource_id: resource_id
+              resource_id: resource_id,
+              client_id: developer_key.global_id
             )
           end
 
-          it_behaves_like 'the line item destroy endpoint'
+          it 'deletes the correct line item' do
+            send_request
+            expect(Lti::LineItem.active.find_by(id: line_item_id)).to be_nil
+          end
+
+          it 'responds with no content' do
+            send_request
+            expect(response).to be_no_content
+          end
         end
       end
     end

spec/factories/line_item_factory.rb

@@ -33,7 +33,8 @@ module Factories
     params = base_line_item_params_with_resource_link(assignment, overrides).merge(
       overrides.except(:assignment, :course, :resource_link, :with_resource_link, :tool)
     )
-    params[:client_id] = DeveloperKey.create!.id unless assignment.external_tool? || overrides[:with_resource_link]
+    params[:client_id] = overrides[:client_id]
+    params[:client_id] ||= DeveloperKey.create!.id unless assignment.external_tool? || overrides[:with_resource_link]
     Lti::LineItem.create!(params)
   end