A node.js module for parsing form data, especially file uploads.
This module was developed for Transloadit, a service focused on uploading and encoding images and videos. It has been battle-tested against hundreds of GB of file uploads from a large variety of clients and is considered production-ready.
- Fast (~500mb/sec), non-buffering multipart parser
- Automatically writing file uploads to disk
- Low memory footprint
- Graceful error handling
- Very high test coverage
Via npm:
npm install formidable@latest
Manually:
git clone git://github.com/felixge/node-formidable.git formidable
vim my.js
# var formidable = require('./formidable');
Note: Formidable requires gently to run the unit tests, but you won't need it for just using the library.
Parse an incoming file upload.
var formidable = require('formidable'),
http = require('http'),
util = require('util');
http.createServer(function(req, res) {
if (req.url == '/upload' && req.method.toLowerCase() == 'post') {
// parse a file upload
var form = new formidable.IncomingForm();
form.parse(req, function(err, fields, files) {
res.writeHead(200, {'content-type': 'text/plain'});
res.write('received upload:\n\n');
res.end(util.inspect({fields: fields, files: files}));
});
return;
}
// show a file upload form
res.writeHead(200, {'content-type': 'text/html'});
res.end(
'<form action="/upload" enctype="multipart/form-data" method="post">'+
'<input type="text" name="title"><br>'+
'<input type="file" name="upload" multiple="multiple"><br>'+
'<input type="submit" value="Upload">'+
'</form>'
);
}).listen(8080);var form = new formidable.IncomingForm()Creates a new incoming form.
form.encoding = 'utf-8';Sets encoding for incoming form fields.
form.uploadDir = process.env.TMP || process.env.TMPDIR || process.env.TEMP || '/tmp' || process.cwd();The directory for placing file uploads in. You can move them later on using
fs.rename(). The default directory is picked at module load time depending on
the first existing directory from those listed above.
form.keepExtensions = false;If you want the files written to form.uploadDir to include the extensions of the original files, set this property to true.
form.typeEither 'multipart' or 'urlencoded' depending on the incoming request.
form.maxFieldsSize = 2 * 1024 * 1024;Limits the amount of memory a field (not file) can allocate in bytes.
If this value is exceeded, an 'error' event is emitted. The default
size is 2MB.
form.hash = false;If you want checksums calculated for incoming files, set this to either 'sha1' or 'md5'.
form.bytesReceivedThe amount of bytes received for this form so far.
form.bytesExpectedThe expected number of bytes in this form.
form.parse(request, [cb]);Parses an incoming node.js request containing form data. If cb is provided, all fields an files are collected and passed to the callback:
form.parse(req, function(err, fields, files) {
// ...
});
form.onPart(part);You may overwrite this method if you are interested in directly accessing the multipart stream. Doing so will disable any 'field' / 'file' events processing which would occur otherwise, making you fully responsible for handling the processing.
form.onPart = function(part) {
part.addListener('data', function() {
// ...
});
}If you want to use formidable to only handle certain parts for you, you can do so:
form.onPart = function(part) {
if (!part.filename) {
// let formidable handle all non-file parts
form.handlePart(part);
}
}Check the code in this method for further inspiration.
file.size = 0The size of the uploaded file in bytes. If the file is still being uploaded (see 'fileBegin' event), this property says how many bytes of the file have been written to disk yet.
file.path = nullThe path this file is being written to. You can modify this in the 'fileBegin' event in
case you are unhappy with the way formidable generates a temporary path for your files.
file.name = nullThe name this file had according to the uploading client.
file.type = nullThe mime type of this file, according to the uploading client.
file.lastModifiedDate = nullA date object (or null) containing the time this file was last written to. Mostly
here for compatibility with the W3C File API Draft.
file.hash = nullIf hash calculation was set, you can read the hex digest out of this var.
form.on('progress', function(bytesReceived, bytesExpected) {
});Emitted after each incoming chunk of data that has been parsed. Can be used to roll your own progress bar.
form.on('field', function(name, value) {
});Emitted whenever a field / value pair has been received.
form.on('fileBegin', function(name, file) {
});Emitted whenever a new file is detected in the upload stream. Use this even if you want to stream the file to somewhere else while buffering the upload on the file system.
Emitted whenever a field / file pair has been received. file is an instance of File.
form.on('file', function(name, file) {
});Emitted when there is an error processing the incoming form. A request that experiences an error is automatically paused, you will have to manually call request.resume() if you want the request to continue firing 'data' events.
form.on('error', function(err) {
});Emitted when the request was aborted by the user. Right now this can be due to a 'timeout' or 'close' event on the socket. In the future there will be a separate 'timeout' event (needs a change in the node core).
form.on('aborted', function() {
});form.on('end', function() {
});Emitted when the entire request has been received, and all contained files have finished flushing to disk. This is a great place for you to send your response.
- Emit progress when content length header parsed (Tim Koschützki)
- Fix Readme syntax due to GitHub changes (goob)
- Replace references to old 'sys' module in Readme with 'util' (Peter Sugihara)
- Strip potentially unsafe characters when using
keepExtensions: true. - Switch to utest / urun for testing
- Add travis build
- Remove file from package that was causing problems when installing on windows. (#102)
- Fix typos in Readme (Jason Davies).
- Do not default to the default to the field name for file uploads where filename="".
- Support filename="" in multipart parts
- Explain unexpected end() errors in parser better
Note: Starting with this version, formidable emits 'file' events for empty file input fields. Previously those were incorrectly emitted as regular file input fields with value = "".
- Detect a good default tmp directory regardless of platform. (#88)
- Fix problems with utf8 characters (#84) / semicolons in filenames (#58)
- Small performance improvements
- New test suite and fixture system
- Exclude node_modules folder from git
- Implement new
'aborted'event - Fix files in example folder to work with recent node versions
- Make gently a devDependency
- Fix package.json to refer to proper main directory. (#68, Dean Landolt)
- Add support for multipart boundaries that are quoted strings. (Jeff Craig)
This marks the beginning of development on version 2.0 which will include several architectural improvements.
- Emit
'progress'event when receiving data, regardless of parsing it. (Tim Koschützki) - Use W3C FileAPI Draft properties for File class
Important: The old property names of the File class will be removed in a future release.
These releases were done before starting to maintain the above Changelog:
- v0.9.10
- v0.9.9
- v0.9.8
- v0.9.7
- v0.9.6
- v0.9.5
- v0.9.4
- v0.9.3
- v0.9.2
- v0.9.1
- v0.9.0
- v0.9.0
- v0.9.0
- v0.9.0
- v0.9.0
- v0.9.0
- v0.9.0
- v0.9.0
- v0.1.0
Formidable is licensed under the MIT license.
- multipart-parser: a C++ parser based on formidable
- Ryan Dahl for his work on http-parser which heavily inspired multipart_parser.js