record last_inline_view time for attachments

to collect data about when scribd (or crocodoc) documents
are not being used and can be purged from third party servers
to save money

fixes CNVS-5310

note: this data is not yet exposed; it can only be queried
from the database manually for now

test plan:  make sure the last_inline_view attribute for an
Attachment is updated whenever the attachment is viewed via
scribd or crocodoc. this can be done in several ways:
 - via the preview icon that appears next to a document link
   in rich text
 - on the files page
 - for student submissions on SpeedGrader

the easiest way to check this is in the Rails console.
get the attachment id from the canvas url, then,
in the console (after switching to the correct shard),
do

  Attachment.find(id).last_inline_view

Change-Id: I137ab631ad4eefdf4d9af353dd11191b7f2ca140
Reviewed-on: https://gerrit.instructure.com/20810
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: James Williams  <jamesw@instructure.com>
Reviewed-by: Bracken Mosbacker <bracken@instructure.com>
Product-Review: Bracken Mosbacker <bracken@instructure.com>
QA-Review: Bracken Mosbacker <bracken@instructure.com>

app/controllers/files_controller.rb

@@ -289,6 +289,7 @@ class FilesController < ApplicationController
         generate_new_page_view
         @attachment.context_module_action(@current_user, :read) if @current_user
         log_asset_access(@attachment, 'files', 'files')
+        @attachment.record_inline_view
         render :json => {:ok => true}.to_json
       else
         render_attachment(@attachment)
@@ -313,10 +314,11 @@ class FilesController < ApplicationController
           # Right now we assume if they ask for json data on the attachment
           # which includes the scribd doc data, then that means they have 
           # viewed or are about to view the file in some form.
-          attachment.context_module_action(@current_user, :read) if @current_user && (
-            (feature_enabled?(:scribd) && attachment.scribd_doc) || 
-            (service_enabled?(:google_docs_previews) && attachment.authenticated_s3_url)
-          )
+          if @current_user && ((feature_enabled?(:scribd) && attachment.scribd_doc) ||
+             (service_enabled?(:google_docs_previews) && attachment.authenticated_s3_url))
+            attachment.context_module_action(@current_user, :read)
+            @attachment.record_inline_view
+          end
           options[:methods] = :authenticated_s3_url if service_enabled?(:google_docs_previews) && attachment.authenticated_s3_url
           log_asset_access(@attachment, "files", "files")
         end

app/helpers/attachment_helper.rb

@@ -38,6 +38,7 @@ module AttachmentHelper
     end
     attrs[:attachment_id] = attachment.id
     attrs[:mimetype] = attachment.mimetype
+    attrs[:attachment_view_inline_ping_url] = context_url(self.context, :context_file_inline_view_url, self.id)
     attrs.inject("") { |s,(attr,val)| s << "data-#{attr}=#{val} " }
   end
 end

app/models/assignment.rb

@@ -1159,6 +1159,10 @@ class Assignment < ActiveRecord::Base
                       :media_comment_type, :media_comment_id,
                       :cached_attachments, :attachments]
 
+    attachment_fields = [:id, :comment_id, :content_type, :context_id, :context_type,
+                         :crocodoc_available?, :display_name, :filename, :mime_class,
+                         :scribd_doc, :scribdable?, :size, :submitter_id, :workflow_state]
+
     res = as_json(
       :include => {
         :context => { :only => :id },
@@ -1197,7 +1201,16 @@ class Assignment < ActiveRecord::Base
             },
             :only => submission_fields,
             :methods => [:versioned_attachments, :late]
-          )
+          ).tap do |s|
+            if s['submission'] && s['submission']['versioned_attachments']
+              s['submission']['versioned_attachments'].map! do |a|
+                a.as_json(
+                  :only => attachment_fields,
+                  :methods => [:view_inline_ping_url]
+                )
+              end
+            end
+          end
         end
       end
       json

app/models/attachment.rb

@@ -1622,4 +1622,12 @@ class Attachment < ActiveRecord::Base
   def crocodoc_available?
     crocodoc_document.try(:available?)
   end
+
+  def view_inline_ping_url
+    "/#{context_url_prefix}/files/#{self.id}/inline_view"
+  end
+
+  def record_inline_view
+    update_attribute(:last_inline_view, Time.now)
+  end
 end

app/views/files/show.html.erb

@@ -41,7 +41,7 @@
     <span style="font-size: 1.2em;">
       <%= link_to "Download #{@attachment.display_name}", download_url %>
     </span> (<%= @attachment.readable_size %>)
-    <div id="doc_preview" <%= doc_preview_attributes(@attachment, :attachment_view_inline_ping_url => context_url(@context, :context_file_inline_view_url, @attachment.id)) %>></div>
+    <div id="doc_preview" <%= doc_preview_attributes(@attachment) %>></div>
   <% end %>
 <% end %>
 <%= render :partial => 'shared/sequence_footer', :locals => {:asset => @attachment} %>

db/migrate/20130521223335_add_last_inline_view_to_attachments.rb

@@ -0,0 +1,11 @@
+class AddLastInlineViewToAttachments < ActiveRecord::Migration
+  tag :predeploy
+
+  def self.up
+    add_column :attachments, :last_inline_view, :datetime
+  end
+
+  def self.down
+    remove_column :attachments, :last_inline_view
+  end
+end

public/javascripts/full_files.js

@@ -311,10 +311,10 @@ define([
         // what value is there in knowing the student looked at the file browser,
         // we just care if they access files.
       },
-      viewFile: function(context_string, id) {
+      viewInlinePingUrl: function(context_string, id) {
         var url = $("#file_context_links ." + context_string + "_inline_view_attachment_url").attr('href');
         url = $.replaceTags(url, 'id', id);
-        $.ajaxJSON(url, 'POST', {}, function() { }, function() { });
+        return url;
       },
       selectFolder: function($original_node) {
         if(!files.selectFolder.forceRefresh && ($original_node.hasClass('active-node') || $original_node.hasClass('active-leaf'))) { return; }
@@ -1578,9 +1578,9 @@ define([
                       height: '100%',
                       crocodoc_session_url: data.crocodocSession,
                       scribd_doc_id: data.scribd_doc && data.scribd_doc.attributes && data.scribd_doc.attributes.doc_id,
-                      scribd_access_key: data.scribd_doc && data.scribd_doc.attributes && data.scribd_doc.attributes.access_key
+                      scribd_access_key: data.scribd_doc && data.scribd_doc.attributes && data.scribd_doc.attributes.access_key,
+                      attachment_view_inline_ping_url: files.viewInlinePingUrl(data.context_string, data.id)
                     });
-                    files.viewFile(data.context_string, data.id);
                   };
                   if (data.permissions && data.permissions.download && $.isPreviewable(data.content_type)) {
                     if (data['crocodoc_available?'] && !data.crocodocSession) {

public/javascripts/speed_grader.js

@@ -1243,6 +1243,7 @@ define([
             mimeType: attachment.content_type,
             attachment_id: attachment.id,
             submission_id: this.currentStudent.submission.id,
+            attachment_view_inline_ping_url: attachment.view_inline_ping_url,
             ready: function(){
               EG.resizeFullHeight();
             }

spec/controllers/files_controller_spec.rb

@@ -272,6 +272,7 @@ describe FilesController do
       get 'show', :course_id => @course.id, :id => @file.id, :download => 1
       @module.reload
       @module.evaluate_for(@user, true, true).state.should eql(:completed)
+      @file.reload.last_inline_view.should be_nil
     end
 
     it "should not mark a file as viewed for module progressions if the file is locked" do
@@ -281,6 +282,7 @@ describe FilesController do
       get 'show', :course_id => @course.id, :id => @file.id, :download => 1
       @module.reload
       @module.evaluate_for(@user, true, true).state.should eql(:unlocked)
+      @file.reload.last_inline_view.should be_nil
     end
 
     it "should not mark a file as viewed for module progressions just because the files#show view is rendered" do
@@ -290,6 +292,7 @@ describe FilesController do
       get 'show', :course_id => @course.id, :id => @file.id
       @module.reload
       @module.evaluate_for(@user, true, true).state.should eql(:unlocked)
+      @file.reload.last_inline_view.should be_nil
     end
 
     it "should mark files as viewed for module progressions if the file is previewed inline" do
@@ -298,6 +301,7 @@ describe FilesController do
       json_parse.should == {'ok' => true}
       @module.reload
       @module.evaluate_for(@user, true, true).state.should eql(:completed)
+      @file.reload.last_inline_view.should > 1.minute.ago
     end
 
     it "should mark files as viewed for module progressions if the file data is requested and it includes the scribd_doc data" do
@@ -307,6 +311,7 @@ describe FilesController do
       get 'show', :course_id => @course.id, :id => @file.id, :format => :json
       @module.reload
       @module.evaluate_for(@user, true, true).state.should eql(:completed)
+      @file.reload.last_inline_view.should > 1.minute.ago
     end
 
     it "should not mark files as viewed for module progressions if the file data is requested and it doesn't include the scribd_doc data (meaning it got viewed in scribd inline) and google docs preview is disabled" do
@@ -322,6 +327,7 @@ describe FilesController do
       get 'show', :course_id => @course.id, :id => @file.id, :format => :json
       @module.reload
       @module.evaluate_for(@user, true, true).state.should eql(:unlocked)
+      @file.reload.last_inline_view.should be_nil
     end
 
     it "should redirect to an existing attachment with the same path as a deleted attachment" do

spec/models/assignment_spec.rb

@@ -2316,6 +2316,17 @@ describe Assignment do
         submission[:late].should == user.submissions.first.late?
       end
     end
+
+    it "should include inline view pingback url for files" do
+      course_with_teacher :active_all => true
+      student_in_course :active_all => true
+      assignment = @course.assignments.create! :submission_types => ['online_upload']
+      attachment = @student.attachments.create! :uploaded_data => dummy_io, :filename => 'doc.doc', :display_name => 'doc.doc', :context => @student
+      submission = assignment.submit_homework @student, :submission_type => :online_upload, :attachments => [attachment]
+      json = assignment.speed_grader_json @teacher
+      attachment_json = json['submissions'][0]['submission_history'][0]['submission']['versioned_attachments'][0]['attachment']
+      attachment_json['view_inline_ping_url'].should match %r{/users/#{@student.id}/files/#{attachment.id}/inline_view\z}
+    end
   end
 
   describe "update_student_submissions" do