Sir Trevor Image block with better upload errorreporting

gistfile1.js

/*
  Simple Image Block
*/

SirTrevor.Blocks.Image = SirTrevor.Block.extend({

  type: "image",
  title: function() { return i18n.t('blocks:image:title'); },

  droppable: true,
  uploadable: true,

  icon_name: 'image',

  loadData: function(data){
    // Create our image tag
    this.$editor.html($('<img>', { src: data.file.url }));
  },

  onBlockRender: function(){
    /* Setup the upload button */
    this.$inputs.find('button').bind('click', function(ev){ ev.preventDefault(); });
    this.$inputs.find('input').on('change', _.bind(function(ev){
      this.onDrop(ev.currentTarget);
    }, this));
  },

  onUploadSuccess : function(data) {
    this.setData(data);
    this.ready();
  },

  onUploadError : function(error){
    // here you should be able to access the responseText from the upload object.
    // If you have returned JSON, parse it and get at the error value, then add it to the message
    this.addMessage([i18n.t('blocks:image:upload_error'), JSON.parse(this.upload.responseText).error].join(' '));
    this.ready();
  },


  onDrop: function(transferData){
    var file = transferData.files[0],
        urlAPI = (typeof URL !== "undefined") ? URL : (typeof webkitURL !== "undefined") ? webkitURL : null;

    // Handle one upload at a time
    if (/image/.test(file.type)) {
      this.loading();
      // Show this image on here
      this.$inputs.hide();
      this.$editor.html($('<img>', { src: urlAPI.createObjectURL(file) })).show();
      
      this.upload = this.uploader(file, this.onUploadSuccess, this.onUploadError);
    }
  }
});