16 KiB
formidable
A Node.js module for parsing form data, especially file uploads.
Important Notes
For more info, check the CHANGELOG on the master branch.
v1 is deprecated
All v1
versions are deprecated in NPM for over 2 years. You can find it at formidable@v1
or formidable@legacy
on NPM, and on v1-legacy branch on GitHub.
We highly recommend to use v2
or v3
. Both are already in use by many, especially v2
which was on formidable@canary
for 2 years.
- Status: Not Maintained!
- We won't provide support or accept reports on that version.
- No Backporting: bugfixes, security fixes, or new features WILL NOT happen!
- Please move to at least v2!
- Try with installing
formidable@v2
and if still have the problem - report!
v2 is the new latest
The v2
will be simultaneously on two places for some time - formidable@latest
and formidable@v2
.
The source code be available only on v2 branch.
If you want to use v2, it's recommended to use the v2 dist-tag formidable@v2
.
Main Differences from v1:
- Better organization and modernized code, requiring newer Node.js versions (>= v10).
- A lot of bugfixes, closed issues, merged or closed PRs.
- Backward compatible to v1! Should not have problems, the major version bump is just for ensurance.
- Better docs, new features (plugins, parsers, options) and optimizations.
v3 - ESModules, Promises, Monorepo structure
We recommend to use formidable@v3
, as it uses more modern Node.js Streams, has support for Promises and more stuff.
You can see more info and track some ideas on issue#635.
- The source code can be found on the master branch on GitHub.
- It will be published on
formidable@latest
after some time. - Dropping older Node.js versions, requiring higher than v12-v14.
- Dropping v1 compatibility.
- Rewritten to ESModules, more optimizations.
- Moving to monorepo structure, more plugins & helper utils.
If you have any how-to kind of questions, please read the Contributing
Guide and Code of Conduct
documents.
For bugs reports and feature requests, please create an
issue or ping @tunnckoCore
at Twitter.
This project is semantically versioned and available as part of the Tidelift Subscription for professional grade assurances, enhanced support and security. Learn more.
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and thousands of other packages are working
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use.
v1 status: not maintained!
Project Status: Maintained
This module was initially developed by @felixge for Transloadit, a service focused on uploading and encoding images and videos. It has been battle-tested against hundreds of GBs of file uploads from a large variety of clients and is considered production-ready and is used in production for years.
Currently, we are few maintainers trying to deal with it. :) More contributors are always welcome! ❤️ Jump on issue #412 which is closed, but if you are interested we can discuss it and add you after strict rules, like enabling Two-Factor Auth in your npm and GitHub accounts.
Features
- Fast (~500mb/sec), non-buffering multipart parser
- Automatically writing file uploads to disk
- Low memory footprint
- Graceful error handling
- Very high test coverage
Installation
npm install formidable@v1
npm install formidable@v2
npm install formidable@v3
This is a low-level package, and if you're using a high-level framework it may already be included. However, Express v4 does not include any multipart handling, nor does body-parser.
Note: Formidable requires gently to run the unit tests, but you won't need it for just using the library.
Example
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);
API
Formidable.IncomingForm
var form = new formidable.IncomingForm()
Creates a new incoming form.
form.encoding = 'utf-8';
Sets encoding for incoming form fields.
form.uploadDir = "/my/dir";
Sets the directory for placing file uploads in. You can move them later on using
fs.rename()
. The default is os.tmpdir()
.
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.type
Either 'multipart' or 'urlencoded' depending on the incoming request.
form.maxFieldsSize = 20 * 1024 * 1024;
Limits the amount of memory all fields together (except files) can allocate in bytes.
If this value is exceeded, an 'error'
event is emitted. The default
size is 20MB.
form.maxFileSize = 200 * 1024 * 1024;
Limits the size of uploaded file.
If this value is exceeded, an 'error'
event is emitted. The default
size is 200MB.
form.maxFields = 1000;
Limits the number of fields that the querystring parser will decode. Defaults to 1000 (0 for unlimited).
form.hash = false;
If you want checksums calculated for incoming files, set this to either 'sha1'
or 'md5'
.
form.multiples = false;
If this option is enabled, when you call form.parse
, the files
argument will contain arrays of files for inputs which submit multiple files using the HTML5 multiple
attribute.
form.bytesReceived
The amount of bytes received for this form so far.
form.bytesExpected
The 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 and 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.
Formidable.File
file.size = 0
The 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 = null
The 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 = null
The name this file had according to the uploading client.
file.type = null
The mime type of this file, according to the uploading client.
file.lastModifiedDate = null
A 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 = null
If hash calculation was set, you can read the hex digest out of this var.
Formidable.File#toJSON()
This method returns a JSON-representation of the file, allowing you to
JSON.stringify()
the file which is useful for logging and responding
to requests.
Events
'progress'
Emitted after each incoming chunk of data that has been parsed. Can be used to roll your own progress bar.
form.on('progress', function(bytesReceived, bytesExpected) {
});
'field'
Emitted whenever a field / value pair has been received.
form.on('field', function(name, value) {
});
'fileBegin'
Emitted whenever a new file is detected in the upload stream. Use this event if you want to stream the file to somewhere else while buffering the upload on the file system.
form.on('fileBegin', function(name, file) {
});
'file'
Emitted whenever a field / file pair has been received. file
is an instance of File
.
form.on('file', function(name, file) {
});
'error'
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) {
});
'aborted'
Emitted when the request was aborted by the user. Right now this can be due to a 'timeout' or 'close' event on the socket. After this event is emitted, an error
event will follow. In the future there will be a separate 'timeout' event (needs a change in the node core).
form.on('aborted', function() {
});
'end'
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.
Changelog
Credits
- multipart-parser: a C++ parser based on formidable
- Ryan Dahl for his work on
http-parser which heavily inspired the
initial
multipart_parser.js
.
From Felix blog post:
- Sven Lito for fixing bugs and merging patches
- egirshov for contributing many improvements to the node-formidable multipart parser
- Andrew Kelley for also helping with fixing bugs and making improvements
- Mike Frey for contributing JSON support
Contributing
If the documentation is unclear or has a typo, please click on the page's Edit
button (pencil icon) and suggest a correction. If you would like to help us fix
a bug or add a new feature, please check our Contributing
Guide. Pull requests are welcome!
License
Formidable is licensed under the MIT License.