course exports use instfs if enabled

closes RECNVS-414

test plan
- with instfs enabled
  - have a course
  - export it
  - verify that the download comes from instfs, not canvas

Change-Id: I18dec04f7c98e85163cd29afeba6b1878a0f62c6
Reviewed-on: https://gerrit.instructure.com/148704
Tested-by: Jenkins
Reviewed-by: Jonathan Featherstone <jfeatherstone@instructure.com>
QA-Review: Collin Parrish <cparrish@instructure.com>
Product-Review: Michael Jasper <mjasper@instructure.com>

lib/cc/cc_exporter.rb

@@ -98,7 +98,8 @@ module CC
           att = Attachment.new
           att.context = @content_export
           att.user = @content_export.user
-          att.uploaded_data = Rack::Test::UploadedFile.new(@export_path, @export_type || Attachment.mimetype(@export_path))
+          data = Rack::Test::UploadedFile.new(@export_path, @export_type || Attachment.mimetype(@export_path))
+          Attachments::Storage.store_for_attachment(att, data)
           if att.save
             @content_export.attachment = att
             @content_export.save

spec/lib/cc/cc_exporter_spec.rb

@@ -200,6 +200,14 @@ describe "Common Cartridge exporting" do
       expect(ccc_schema.validate(doc)).to be_empty
     end
 
+    it "should use instfs to host export files if it is enabled" do
+      allow(InstFS).to receive(:enabled?).and_return(true)
+      uuid = "1234-abcd"
+      allow(InstFS).to receive(:direct_upload).and_return(uuid)
+      @ce.export_without_send_later
+      expect(@ce.attachments.first.instfs_uuid).to eq(uuid)
+    end
+
     it "should create a quizzes-only export" do
 
       @q1 = @course.quizzes.create!(:title => 'quiz1')