Uploading files in chunks and reading chunks to return the original files in Nodejs
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Below is the upload function
exports.uploadFilesChunk = (req, res) => {
var form = new formidable.IncomingForm()
form.parse(req, (err, fields, files) => {
const readStream = fs.createReadStream(files.demo_image.path, { highWaterMark: 30 * 1024 });
let createFileNameToUpload = files.demo_image.name.split(‘.’)
var dir = __dirname + ‘/../uploads/’ + createFileNameToUpload[0]
readStream.setEncoding(‘utf8’);
fileNameToUpload = files.demo_image.name.split(‘.’).join(‘-’ + Date.now() + ‘.’);
var writableStream = fs.createWriteStream(dir + ‘/’ + fileNameToUpload + “.part.gzip”);
if (!fs.existsSync(dir)) {
fs.mkdirSync(dir);
}
readStream.on(‘data’, (chunk) => {
const gzipStream = zlib.createGzip(chunk);
writableStream.write(gzipStream.toString());
});
readStream.pipe(writableStream);
})
}
Note :- So you can do basic check like checking the file size first and then start uploading the files. If file size is less than 2MB or 4 MB then you better upload them directly on the server. For this please import const zlib = require('zlib'); const formidable = require(‘formidable’);
Below is the function to read chunks and return original file
exports.readUploadedChunk = (req, res) => {
var form = new formidable.IncomingForm()
form.parse(req, (err, fields, files) => {
const directoryPath = path.join(__dirname + ‘/../uploads/’ + fields.file_name);
var writableStream = fs.createWriteStream(__dirname + ‘/../uploads/’ + fields.file_name);
fs.readdir(directoryPath, function (err, files) {
if (err) {
return console.log(‘Unable to scan directory: ‘ + err);
}
//listing all files using forEach
const filesDataDir = files.filter(a => a.endsWith(‘.part.gzip’));
filesDataDir.forEach(function (file) {
// Do whatever you want to do with the file
fs.readFile(__dirname + ‘/../uploads/’ + fields.file_name + ‘/’ + file, (err, data) => {
if (err) throw err;
console.log(data);
writableStream.write(data);
});
});
});
})
}
You can test above both functions using postman. Please let me know in-case of any issues/improvements.
