fix presentation_return_url to include the host

fixed PLAT-1114

test-plan:
do an lti launch from an assignment, and module.
the launch_presentation_return_url should always have a full url

Change-Id: I6ed257310181d24d5c9f0f2261aebe2781062fa9
Reviewed-on: https://gerrit.instructure.com/55970
Tested-by: Jenkins
Reviewed-by: Brad Humphrey <brad@instructure.com>
QA-Review: August Thornton <august@instructure.com>
Product-Review: Nathan Mills <nathanm@instructure.com>

app/controllers/application_controller.rb

@@ -1260,7 +1260,7 @@ class ApplicationController < ActionController::Base
           @return_url = success_url
         else
           if @context
-            @return_url = named_context_url(@context, :context_external_content_success_url, 'external_tool_redirect')
+            @return_url = named_context_url(@context, :context_external_content_success_url, 'external_tool_redirect', include_host: true)
           else
             @return_url = external_content_success_url('external_tool_redirect')
           end

spec/controllers/application_controller_spec.rb

@@ -512,6 +512,40 @@ describe ApplicationController do
       controller.stubs(:redirect_to)
       controller.send(:content_tag_redirect, Account.default, tag, nil)
     end
+
+    context 'ContextExternalTool' do
+
+      let(:course){ course_model }
+
+      let(:tool) do
+        tool = course.context_external_tools.new(
+          name: "bob",
+          consumer_key: "bob",
+          shared_secret: "bob",
+          tool_id: 'some_tool',
+          privacy_level: 'public'
+        )
+        tool.url = "http://www.example.com/basic_lti"
+        tool.resource_selection = {
+          :url => "http://#{HostUrl.default_host}/selection_test",
+          :selection_width => 400,
+          :selection_height => 400}
+        tool.save!
+        tool
+      end
+
+      let(:content_tag) { ContentTag.create(content: tool, url: tool.url)}
+
+      it 'returns the full path for the redirect url' do
+        controller.expects(:named_context_url).with(course, :context_url, {:include_host => true})
+        controller.expects(:named_context_url).with(course, :context_external_content_success_url, 'external_tool_redirect', {:include_host => true}).returns('wrong_url')
+        controller.stubs(:render)
+        controller.stubs(js_env:[])
+        controller.instance_variable_set(:"@context", course)
+        controller.send(:content_tag_redirect, course, content_tag, nil)
+      end
+    end
+
   end
 
   describe 'external_tools_display_hashes' do

spec/integration/external_tools_spec.rb

@@ -42,7 +42,7 @@ describe "External Tools" do
       expect(form.at_css('input#launch_presentation_locale')['value']).to eq 'en'
       expect(form.at_css('input#oauth_callback')['value']).to eq 'about:blank'
       expect(form.at_css('input#oauth_signature_method')['value']).to eq 'HMAC-SHA1'
-      expect(form.at_css('input#launch_presentation_return_url')['value']).to eq "/courses/#{@course.id}/external_content/success/external_tool_redirect"
+      expect(form.at_css('input#launch_presentation_return_url')['value']).to eq "http://www.example.com/courses/#{@course.id}/external_content/success/external_tool_redirect"
       expect(form.at_css('input#lti_message_type')['value']).to eq "basic-lti-launch-request"
       expect(form.at_css('input#lti_version')['value']).to eq "LTI-1p0"
       expect(form.at_css('input#oauth_version')['value']).to eq "1.0"