sails.js req.file.upload with bluebird promise - upload

Question

I'm using sails.js as my backend with bluebird promise, I tried to upload file using req.file.upload, the callback way works just fine and the file gets uploaded:
req.file('file').upload({
maxBytes: 2000000,
dirname: 'uploadFolder'
}, function (err, files) {
if (err) {
return res.serverError(err);
}
return res.ok();
}
But the promise way does not:
var Promise = require('bluebird');
var fileUploader = Promise.promisify(req.file('file').upload);
fileUploader({
maxBytes: 2000000,
dirname: currentUploadFolder
}).then(function(files) {
console.log(files);
return Promise.resolve(files);
}).catch(function(err) {
console.log(err);
return Promise.reject(err);
});
File doesn't get uploaded and the console keeps complaining:
data: app.js:1800 - [TypeError: Cannot read property 'length' of undefined]
Any thoughts please?

Answer 1

This case is unique and you can't use promisify here. You need to create new Promise and return it.
return new Promise(function(resolve, reject) {
req.file('file').upload({
maxBytes: 2000000,
dirname: 'uploadFolder'
}, function (error, files) {
return error ? reject(error) : resolve(files);
}
});
You can move it to helper\services\whatever and got something like this
// api/services/UploadService.js
module.exports = {
uploadFile: function(req) {
return new Promise(function(resolve, reject) {
req.file('file').upload({
maxBytes: 2000000,
dirname: 'uploadFolder'
}, function (error, files) {
return error ? reject(error) : resolve(files);
}
});
}
};
// api/controllers/AnyController.js
module.exports = {
upload: function(req, res) {
UploadService
.uploadFile(req)
.then(res.ok)
.catch(res.negotiate);
}
};