AngularJS directive for Dropzone.js

dropzone-directive.js

/**
 * An AngularJS directive for Dropzone.js, http://www.dropzonejs.com/
 * 
 * Usage:
 * 
 * <div ng-app="app" ng-controller="SomeCtrl">
 *   <button dropzone="dropzoneConfig">
 *     Drag and drop files here or click to upload
 *   </button>
 * </div>
 */

angular.module('dropzone', []).directive('dropzone', function () {
  return function (scope, element, attrs) {
    var config, dropzone;

    config = scope[attrs.dropzone];

    // create a Dropzone for the element with the given options
    dropzone = new Dropzone(element[0], config.options);

    // bind the given event handlers
    angular.forEach(config.eventHandlers, function (handler, event) {
      dropzone.on(event, handler);
    });
  };
});

angular.module('app', ['dropzone']);

angular.module('app').controller('SomeCtrl', function ($scope) {
  $scope.dropzoneConfig = {
    'options': { // passed into the Dropzone constructor
      'url': 'upload.php'
    },
    'eventHandlers': {
      'sending': function (file, xhr, formData) {
      },
      'success': function (file, response) {
      }
    }
  };
});

I am getting Error
Cannot read property 'options' of undefined
The line I am pointed to is
dropzone = new Dropzone(element[0], config.options);

my Directive is:

'use strict';

angular.module('myModuleName').directive('ngDropzone', function () {
	return {
        restrict: 'A',
        link: function (scope, element, attrs) {
        	var config, dropzone;
        	config = scope[attrs.dropzone];
        	
        	// create a Dropzone for the element with the given options
        	dropzone = new Dropzone(element[0], config.options);
        	
        	// bind the given event handlers
        	angular.forEach(config.eventHandlers, function (handler, event) {
        		dropzone.on(event, handler);
        	});
        }
	};
});

my HTML is:

<button data-ng-dropzone="dropzoneConfig">
	Drag and drop files here or click to upload
</button>

my Controller is:

	
	$scope.dropzoneConfig = {
		    'options': { // passed into the Dropzone constructor
//		    	'url': 'upload.php'
		    	'url': null,
		    	'maxFiles': 1,
		    	'autoProcessQueue': false,
		    },
		    'eventHandlers': {
		      'sending': function (file, formData, xhr) {
		    	  console.log(file);
		    	  console.log(formData);
		    	  console.log(xhr);
		      },
		      'success': function (file, response) {
		    	  console.log(file);
		    	  console.log(response);
		      }
		    }
		  };

What am I missing???