A Node.js module for parsing form data, especially file uploads.
For more info, check the CHANGELOG on the master branch.
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.
formidable@v2 and if still have the problem - report!latestThe 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.
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.
formidable@latest after some time.
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.
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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! :heart: 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.
sh
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.
Parse an incoming file upload. ```javascript 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( '
' ); }).listen(8080); ```javascript
var form = new formidable.IncomingForm()
Creates a new incoming form.
javascript
form.encoding = 'utf-8';
Sets encoding for incoming form fields.
javascript
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().
javascript
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.
javascript
form.type
Either 'multipart' or 'urlencoded' depending on the incoming request.
javascript
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.
javascript
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.
javascript
form.maxFields = 1000;
Limits the number of fields that the querystring parser will decode. Defaults
to 1000 (0 for unlimited).
javascript
form.hash = false;
If you want checksums calculated for incoming files, set this to either 'sha1' or 'md5'.
javascript
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.
javascript
form.bytesReceived
The amount of bytes received for this form so far.
javascript
form.bytesExpected
The expected number of bytes in this form.
javascript
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:
```javascript 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.
javascript
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:
javascript
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.
javascript
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.
javascript
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.
javascript
file.name = null
The name this file had according to the uploading client.
javascript
file.type = null
The mime type of this file, according to the uploading client.
javascript
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.
javascript
file.hash = null
If hash calculation was set, you can read the hex digest out of this var.
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.
Emitted after each incoming chunk of data that has been parsed. Can be used to roll your own progress bar.
javascript
form.on('progress', function(bytesReceived, bytesExpected) {
});
Emitted whenever a field / value pair has been received.
javascript
form.on('field', function(name, value) {
});
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.
javascript
form.on('fileBegin', function(name, file) {
});
Emitted whenever a field / file pair has been received. file is an instance of File.
javascript
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.
javascript
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. 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).
javascript
form.on('aborted', function() {
});
javascript
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.
multipart_parser.js.From Felix blog post:
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!
Formidable is licensed under the MIT License.