create the media object for submissions and comments if it doesn't exist

Check Kaltura to verify the media id is valid, then create the object,
so that we can track it as we normally do.

fixes #5775

also update some of the submission api documentation around media
comments and file uploads.

test plan: there isn't a UI to show media objects yet, so you'll have to
have console/db access. submit a video/audio submission comment through
the API, then verify that after jobs run, a MediaObject exists for the
media id you gave.

Change-Id: Id0f5b4cdc23330ea952e674df4fc0d1f1c81bf23
Reviewed-on: https://gerrit.instructure.com/12245
Reviewed-by: Simon Williams <simon@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>

app/controllers/submissions_api_controller.rb

@@ -181,7 +181,7 @@ class SubmissionsApiController < ApplicationController
     end
   end
 
-  # @API Grade a submission
+  # @API Grade or comment on a submission
   #
   # Comment on and/or update the grading for a student's assignment submission.
   # If any submission or rubric_assessment arguments are provided, the user
@@ -192,6 +192,13 @@ class SubmissionsApiController < ApplicationController
   #
   # @argument comment[group_comment] [Boolean] Whether or not this comment should be sent to the entire group (defaults to false). Ignored if this is not a group assignment or if no text_comment is provided.
   #
+  # @argument comment[media_comment_id] Add an audio/video comment to the submission.
+  #   Media comments can be added via this API, however, note that there
+  #   is not yet an API to generate or list existing media comments, so this
+  #   functionality is currently of limited use.
+  #
+  # @argument comment[media_comment_type] ["audio"|"video"] The type of media comment being added.
+  #
   # @argument submission[posted_grade] Assign a score to the submission,
   #   updating both the "score" and "grade" fields on the submission record.
   #   This parameter can be passed in a few different formats:
@@ -278,11 +285,6 @@ class SubmissionsApiController < ApplicationController
       if comment.is_a?(Hash)
         comment = {
           :comment => comment[:text_comment], :author => @current_user }.merge(
-          # Undocumented API feature: adding media comments given the kaltura
-          # media id. Eventually we'll expose a public API for media comments,
-          # but we need to implement a way to abstract it away from kaltura and
-          # make it generic. This will probably involve a proxy outside of
-          # rails.
           comment.slice(:media_comment_id, :media_comment_type, :group_comment)
         ).with_indifferent_access
         @assignment.update_submission(@submission.user, comment)

app/controllers/submissions_controller.rb

@@ -239,8 +239,7 @@ class SubmissionsController < ApplicationController
   #   one or more previously uploaded files residing in the submitting user's
   #   files section (or the group's files section, for group assignments).
   #
-  #   There is not yet an API for listing a user's or group's files, or
-  #   uploading files for submission. This API is coming soon.
+  #   To upload a new file to submit, see the submissions {api:SubmissionsApiController#create_file Upload a file API}.
   #
   #   Requires a submission_type of "online_upload".
   #

app/models/media_object.rb

@@ -155,7 +155,27 @@ class MediaObject < ActiveRecord::Base
       build_media_objects(res, root_account_id)
     end
   end
-  
+
+  def self.media_id_exists?(media_id)
+    client = Kaltura::ClientV3.new
+    client.startSession(Kaltura::SessionType::ADMIN)
+    info = client.mediaGet(media_id)
+    return !!info[:id]
+  end
+
+  def self.ensure_media_object(media_id, create_opts = {})
+    if !by_media_id(media_id).any?
+      self.send_later_enqueue_args(:create_if_id_exists, { :priority => Delayed::LOW_PRIORITY }, media_id, create_opts)
+    end
+  end
+
+  # typically call this in a delayed job, since it has to contact kaltura
+  def self.create_if_id_exists(media_id, create_opts = {})
+    if media_id_exists?(media_id) && !by_media_id(media_id).any?
+      create!(create_opts.merge(:media_id => media_id))
+    end
+  end
+
   def update_title_on_kaltura
     client = Kaltura::ClientV3.new
     client.startSession(Kaltura::SessionType::ADMIN)
@@ -251,7 +271,6 @@ class MediaObject < ActiveRecord::Base
   def data
     self.read_attribute(:data) || self.write_attribute(:data, {})
   end
-  
 
   def viewed!
     send_later(:updated_viewed_at_and_retrieve_details, Time.now) if !self.data[:last_viewed_at] || self.data[:last_viewed_at] > 1.hour.ago

app/models/submission.rb

@@ -106,6 +106,7 @@ class Submission < ActiveRecord::Base
   after_save :update_final_score
   after_save :submit_to_turnitin_later
   after_save :update_admins_if_just_submitted
+  after_save :check_for_media_object
   after_save :update_quiz_submission
 
   def self.needs_grading_trigger_sql
@@ -481,6 +482,15 @@ class Submission < ActiveRecord::Base
     end
     true
   end
+
+  def check_for_media_object
+    if self.media_comment_id.present? && self.media_comment_id_changed?
+      MediaObject.ensure_media_object(self.media_comment_id, {
+        :user => self.user,
+        :context => self.user,
+      })
+    end
+  end
   
   def submission_history
     res = []

app/models/submission_comment.rb

@@ -27,8 +27,6 @@ class SubmissionComment < ActiveRecord::Base
   has_many :associated_attachments, :class_name => 'Attachment', :as => :context
   has_many :submission_comment_participants, :dependent => :destroy
   has_many :messages, :as => :context, :dependent => :destroy
-  # too bad, this wont work.
-  # has_many :comments_in_group, :class_name => "SubmissionComment", :foreign_key => "group_comment_id", :primary_key => "group_comment_id", :dependent => :destroy, :conditions => lambda{|sc| "id !=#{sc.id}"}
 
   validates_length_of :comment, :maximum => maximum_text_length, :allow_nil => true, :allow_blank => true
   validates_length_of :comment, :minimum => 1, :allow_nil => true, :allow_blank => true
@@ -37,6 +35,7 @@ class SubmissionComment < ActiveRecord::Base
 
   before_save :infer_details
   after_save :update_submission
+  after_save :check_for_media_object
   after_destroy :delete_other_comments_in_this_group
   after_create :update_participants
   after_create { |c| c.submission.create_or_update_conversations!(:create) if c.send_to_conversations? }
@@ -62,6 +61,15 @@ class SubmissionComment < ActiveRecord::Base
     self.media_comment_id && self.media_comment_type
   end
 
+  def check_for_media_object
+    if self.media_comment? && self.media_comment_id_changed?
+      MediaObject.ensure_media_object(self.media_comment_id, {
+        :user => self.author,
+        :context => self.author,
+      })
+    end
+  end
+
   on_create_send_to_streams do
     if self.submission
       if self.author_id == self.submission.user_id
@@ -209,8 +217,4 @@ class SubmissionComment < ActiveRecord::Base
   named_scope :for_context, lambda{|context|
     {:conditions => ['submission_comments.context_id = ? AND submission_comments.context_type = ?', context.id, context.class.to_s] }
   }
-  # protected :infer_details
-  # named_scope :for, lambda {|user|
-    # {:conditions => ['(submission_comments.recipient_id IS NULL OR submission_comments.recipient_id = ?)', (user ? user.id : 0)]}
-  # }
 end

spec/models/media_object_spec.rb

@@ -50,4 +50,31 @@ describe MediaObject do
       @a2.reload.file_state.should == 'available'
     end
   end
+
+  describe ".ensure_media_object" do
+    it "should not create if the media object exists already" do
+      MediaObject.create!(:context => user, :media_id => "test")
+      expect {
+        MediaObject.ensure_media_object("test", {})
+      }.to change(Delayed::Job, :count).by(0)
+    end
+
+    it "should not create if the media id doesn't exist in kaltura" do
+      MediaObject.expects(:media_id_exists?).with("test").returns(false)
+      expect {
+        MediaObject.ensure_media_object("test", {})
+        run_jobs
+      }.to change(MediaObject, :count).by(0)
+    end
+
+    it "should create the media object" do
+      MediaObject.expects(:media_id_exists?).with("test").returns(true)
+      expect {
+        MediaObject.ensure_media_object("test", { :context => user })
+        run_jobs
+      }.to change(MediaObject, :count).by(1)
+      obj = MediaObject.by_media_id("test").first
+      obj.context.should == @user
+    end
+  end
 end

spec/models/submission_comment_spec.rb

@@ -158,6 +158,14 @@ This text has a http://www.google.com link in it...
     @item.data.submission_comments[0].formatted_body.should eql(@comment.formatted_body(250))
   end
 
+  it "should ensure the media object exists" do
+    assignment_model
+    se = @course.enroll_student(user)
+    @submission = @assignment.submit_homework(se.user, :body => 'some message')
+    MediaObject.expects(:ensure_media_object).with("fake", { :context => se.user, :user => se.user })
+    @comment = @submission.add_comment(:author => se.user, :media_comment_type => 'audio', :media_comment_id => 'fake')
+  end
+
   context "conversations" do
     before do
       assignment_model

spec/models/submission_spec.rb

@@ -104,6 +104,13 @@ describe Submission do
     @submission.conversation_groups.should eql @submission.conversation_groups.uniq
   end
 
+  it "should ensure the media object exists" do
+    assignment_model
+    se = @course.enroll_student(user)
+    MediaObject.expects(:ensure_media_object).with("fake", { :context => se.user, :user => se.user })
+    @submission = @assignment.submit_homework(se.user, :media_comment_id => "fake", :media_comment_type => "audio")
+  end
+
   context "Discussion Topic" do
     it "should use correct date for its submitted_at value" do
       course_with_student_logged_in(:active_all => true)