如何在express.bodyParser中设置defer = true时返回新文件名

Question

express config：

server.configure(function () {
server.use(express.bodyParser({
    keepExtensions:true,
    limit:100000000,
    defer:true,
    uploadDir: "d:/"})
);

上传控制器：

exports.upload = function(req, res){
    req.form.on('progress',function(bytesReceived, bytesExpected){
        res.send({loaded: bytesReceived, total: bytesExpected});
    });
    req.form.on('complete',function(){
        if(!path.existsSync(uploadDir)){
            mkdirp(uploadDir, function (err) {
                if (err) console.error(err)
                saveImg(req, res);
            });
        } else {
            saveImg(req, res);
        }
    });
};

var saveImg = function(req, res) {
    var scrName =  req.files.files[0].path;
    var distName = uploadDir + uuid.v4() + '.png';
    var gm = require('gm');
    gm(scrName)
        .resize(1000, 1000)
        .autoOrient()
        .write(distName, function (err) {
            fs.unlink(scrName);
            // res.send({distName: distName});
        });
}

虽然我没有调用“res.send（{distName：distName}）”，但是当上传成功时客户端会得到响应，那么如何在jquery代码中获取新的图像名称如下所示：

$('#fileupload').fileupload({
        url: Vari.ApiPath + 'upload',
        dataType: 'json',
        done: function (e, data) {
            console.log(data.distName);

        },
        progressall: function (e, data) {
            var progress = parseInt(data.loaded / data.total * 100, 10);
            $('#progress .progress-bar').css(
                'width',
                progress + '%'
            );
        }
    }).prop('disabled', !$.support.fileInput)
        .parent().addClass($.support.fileInput ? undefined : 'disabled');