Allow plagiarism tool providers to set eula link

Refs PLAT-2878

Test Plan:
- Install a plagiarim tool that offers a service named
  'vnd.Canvas.Eula'. Example:
  {"endpoint"=>"http://originality.docker/eula",
   "action"=>["GET"],
   "@id"=>"http://originality.docker/lti/v2/services#vnd.Canvas.Eula",
   "@type"=>"RestService"}
- Associate the tool with an assignment.
- As a student go to the assignment submission page.
  Verify a link to the EULA is shown on the page.

Change-Id: I86d9f06609e241e302f72b1f7569054b70c6674a
Reviewed-on: https://gerrit.instructure.com/129690
Reviewed-by: Nathan Mills <nathanm@instructure.com>
QA-Review: August Thornton <august@instructure.com>
Tested-by: Jenkins
Product-Review: Karl Lloyd <karl@instructure.com>

app/controllers/assignments_controller.rb

@@ -164,7 +164,14 @@ class AssignmentsController < ApplicationController
       @similarity_pledge = pledge_text
 
       respond_to do |format|
-        format.html { render }
+        format.html do
+          render locals: {
+            eula_url: @assignment.tool_settings_tool
+                      &.try(:tool_proxy)
+                      &.find_service(Assignment::Lti::EULA_SERVICE, 'GET')
+                      &.endpoint
+          }
+        end
         format.json { render :json => @assignment.as_json(:permissions => {:user => @current_user, :session => session}) }
       end
     end

app/models/assignment.rb

@@ -42,6 +42,8 @@ class Assignment < ActiveRecord::Base
   OFFLINE_SUBMISSION_TYPES = %i(on_paper external_tool none not_graded wiki_page).freeze
   SUBMITTABLE_TYPES = %w(online_quiz discussion_topic wiki_page).freeze
 
+  Lti::EULA_SERVICE = 'vnd.Canvas.Eula'.freeze
+
   attr_accessor :previous_id, :updating_user, :copying, :user_submitted
 
   attr_reader :assignment_changed

app/models/lti/tool_proxy.rb

@@ -138,5 +138,11 @@ module Lti
         tool_resource_type_code: message_handler&.resource_handler&.resource_type_code
       ).preload(:assignment).map(&:assignment)
     end
+
+    def find_service(service_id, action)
+      ims_tool_proxy.tool_profile&.service_offered&.find do |s|
+        s.id.include?(service_id) && s.action.include?(action)
+      end
+    end
   end
 end

app/views/assignments/_submit_assignment.html.erb

@@ -122,7 +122,12 @@
           <td colspan="2">
             <label class='checkbox'>
               <input type="checkbox" class='turnitin_pledge' name="turnitin_pledge" value="1"/>
-              <%= @similarity_pledge %>
+              <% if eula_url.present? %>
+                <%= t "I agree to the tool's" %>
+                <%= raw("<a href='#{eula_url}'>#{t 'End-User License Agreement.'}</a>") %>
+              <% else %>
+                <%= @similarity_pledge %>
+              <% end %>
             </label>
           </td>
         </tr>

app/views/assignments/show.html.erb

@@ -235,7 +235,7 @@
 <% end %>
 
 <% if !@locked && can_do(@assignment, @current_user, :submit) %>
-  <%= render :partial => "submit_assignment" %>
+  <%= render :partial => "submit_assignment", locals: { eula_url: eula_url }%>
 <% end %>
 
 <%= render partial: "shared/rubrics_component" %>

lib/lti/assignment_subscriptions_helper.rb

@@ -76,10 +76,7 @@ module Lti
 
     def submission_event_service
       @_submission_event_service ||= begin
-        tp = IMS::LTI::Models::ToolProxy.from_json(tool_proxy.raw_data)
-        tp.tool_profile&.service_offered&.find do |s|
-          s.id.include?(SUBMISSION_EVENT_ID) && s.action.include?("POST")
-        end
+        tool_proxy.find_service(SUBMISSION_EVENT_ID, 'POST')
       end
     end
 

spec/models/lti/tool_proxy_spec.rb

@@ -496,6 +496,45 @@ module Lti
       end
     end
 
+    describe "#find_service" do
+      let(:service_one_id) { "http://originality.docker/lti/v2/services#vnd.Canvas.SubmissionEvent" }
+      let(:service_one_endpoint) { "http://originality.docker/event/submission" }
+      let(:service_two_id) { "http://originality.docker/lti/v2/services#vnd.Canvas.Eula" }
+      let(:service_two_endpoint) { "http://originality.docker/eula" }
+      let(:tool_proxy) do
+        create_tool_proxy(raw_data: {
+          'tool_profile' => {
+            'service_offered' => [
+              {
+                "endpoint" => service_one_endpoint,
+                "action" => ["POST", "GET"],
+                "@id" => service_one_id,
+                "@type" => "RestService"
+              },
+              {
+                "endpoint" => service_two_endpoint,
+                "action" => ["GET"],
+                "@id" => service_two_id,
+                "@type" => "RestService"
+              }
+            ]
+          }
+        })
+      end
+
+      it 'returns the service for the specified id/action pair' do
+        expect(tool_proxy.find_service(service_one_id, 'POST').endpoint).to eq service_one_endpoint
+      end
+
+      it 'considers all actions of potential services' do
+        expect(tool_proxy.find_service(service_one_id, 'GET').endpoint).to eq service_one_endpoint
+      end
+
+      it 'does not return a service if no matching action is found' do
+        expect(tool_proxy.find_service(service_one_id, 'PUT')).to be_nil
+      end
+    end
+
     describe "#ims_tool_proxy" do
       it 'gets the ims-lti gem version of the tool proxy' do
         tool_proxy_guid = '123'

spec/views/assignments/show.html.erb_spec.rb

@@ -17,6 +17,7 @@
 #
 
 require File.expand_path(File.dirname(__FILE__) + '/../../spec_helper')
+require File.expand_path(File.dirname(__FILE__) + '/../../lti2_spec_helper')
 require File.expand_path(File.dirname(__FILE__) + '/../views_helper')
 
 describe "/assignments/show" do
@@ -33,5 +34,41 @@ describe "/assignments/show" do
     render 'assignments/show'
     expect(response).not_to be_nil # have_tag()
   end
-end
 
+  context 'plagiarism platform' do
+    include_context 'lti2_spec_helper'
+
+    let(:eula_url) { 'https://www.test.com/eula' }
+    let(:eula_service) do
+      {
+        "endpoint" => eula_url,
+        "action" => ["GET"],
+        "@id" => 'http://www.test.com/lti/v2/services#vnd.Canvas.Eula',
+        "@type" => "RestService"
+      }
+    end
+
+    before do
+      allow_any_instance_of(Assignment).to receive(:multiple_due_dates?) { true }
+      allow(view).to receive(:eula_url) { eula_url }
+    end
+
+    it 'renders the eula url if present' do
+      tool_proxy.raw_data['tool_profile']['service_offered'] << eula_service
+      tool_proxy.resources << resource_handler
+      tool_proxy.save!
+
+      course_with_student(active_all: true)
+      view_context(@course, @student)
+
+      a = @course.assignments.create!(:title => "some assignment", :submission_types => 'online_upload')
+      allow(a).to receive(:tool_settings_tool) { message_handler }
+      assign(:assignment, a)
+      assign(:current_user_rubrics, [])
+      assign(:external_tools, [])
+
+      render 'assignments/show'
+      expect(rendered).to include "<a href='https://www.test.com/eula'>End-User License Agreement.</a>"
+    end
+  end
+end