Upload file in angularJs

uploadFile.js

$resource('/path/to/api/resource', null, {
            upload: {
                method: 'POST',
                headers: { 'Content-Type': undefined },
                transformRequest: function (data) {
                    var formData = new FormData();

                    formData.append("data", angular.toJson(data.model));

                    angular.forEach(data.files, function (fileData) {
                        formData.append(fileData.name, fileData.binary);
                    });

                    return formData;
                }
            }
        });