raise exceptions when attachment already exists

app/controllers/chunks_controller.rb

@@ -59,11 +59,16 @@ class ChunksController < ApplicationController
         puts "File saved to #{resumable_filename}"
       end
 
-      publisher = LearningObjectPublisher.new(DspaceService.create_client)
-      publisher.post @learning_object, resumable_filename
+      begin
+        status = 200
+        publisher = LearningObjectPublisher.new(DspaceService.create_client)
+        publisher.post @learning_object, resumable_filename
+      rescue LearningObject::DuplicateAttachmentError => e
+        status = 406
+      end
     end
 
-    render :nothing => true, :status => 200
+    render :nothing => true, :status => status
   end
 
   private

app/models/learning_object/duplicate_attachment_checker.rb

+module LearningObject::DuplicateAttachmentChecker
+
+  def self.check_duplicates(learning_object, media_path)
+    file_size = File.size media_path
+    file_name = File.basename media_path
+
+    learning_object.attachments.each do |learning_object|
+      if attachment.size == file_size && attachment.name == file_name
+        return true
+      end
+    end
+  end
+
+  def self.check_duplicates!(learning_object, media_path)
+    if check_duplicates learning_object, media_path
+      raise DuplicateAttachmentError, 'The attachment already exists!'
+    end
+  end
+
+end

app/models/learning_object/duplicate_attachment_error.rb

+class LearningObject::DuplicateAttachmentError < StandardError; end
\ No newline at end of file

app/services/learning_object_publisher.rb

@@ -13,7 +13,10 @@ class LearningObjectPublisher
     learning_object_repository.create draft
   end
 
+  #post *media_path* to *learning_object* on dspace
+  #raise LearningObject::DuplicateAttachmentError if *media_path* already exists
   def post(learning_object, media_path)
+    check_duplicate_attachments! learning_object, media_path
     DspaceUploadWorker.perform_async learning_object.id, learning_object.id_dspace, media_path
   end
 
@@ -25,6 +28,10 @@ class LearningObjectPublisher
 
   private
 
+  def check_duplicate_attachments!(learning_object, media_path)
+    LearningObject::DuplicateAttachmentChecker.check_duplicates! learning_object, media_path
+  end
+
   # change *learning_object* status to active
   def activate!(learning_object)
     learning_object.status = 'active'

app/views/learning_objects/_file_upload_form.html.erb

@@ -144,6 +144,10 @@
       $('[data-uniqueId=' + file.uniqueIdentifier + ']').find('.progress-bar').addClass('progress-bar-success');
     });
 
+    r.on('fileError', function (file, message) {
+      $('[data-uniqueId=' + file.uniqueIdentifier + ']').find('.progress-bar').addClass('progress-bar-danger');
+      $('[data-uniqueId=' + file.uniqueIdentifier + ']').find('.progress-bar').html(' ' + messages);
+    });
 
     r.on('uploadStart', function () {
       $('#upload_message').text('Enviando, aguarde...');

app/workers/dspace_upload_worker.rb

@@ -4,12 +4,12 @@ class DspaceUploadWorker
 
   @@dspace= nil
 
-  def perform(learning_object_id, item_id, media_path)
+  def perform(learning_object_id, item_id, media_path, *options)
     # create file instance
     file = File.new(media_path, 'r')
 
     #create bitstream in dspace
-    bitstream = dspace.items.add_bitstream(file, id: item_id, name: File.basename(media_path), description: 'beta upload')
+    bitstream = dspace.items.add_bitstream(file, id: item_id, name: File.basename(media_path), description: get_description(options))
 
     #find learning object
     learning_object = learning_object_repository.find learning_object_id
@@ -35,4 +35,12 @@ class DspaceUploadWorker
     @@dspace ||= DspaceService.create_client
   end
 
+  def get_description(*options)
+    description = nil
+    if options.has_key? :description
+      description = options[:description]
+    end
+    description
+  end
+
 end