How can I load an Excel file uploaded by nodejs?

Question

I am using the 'mongo-xlsx' module. But the last line doesn't work.

router.post("/xlsx",upload.single('file'), function(req, res){


var data = xlsx.parse(fs.readFileSync(__dirname + '/'+req.file.filename));
console.log(data[0].data);
var data2 = data[0].data;
var model=mongoXlsx.buildDynamicModel(data2);
console.log(model);
mongoXlsx.xlsx2MongoData("./file.xlsx", model, function(err, mongoData) {
    console.log('Mongo data:', mongoData); 
  });


});