JarCastingDescription
A node.js module for parsing incoming HTML form data.
Requirements
- node.js -- v4.5.0 or newer
Install
npm install busboy
Examples
- Parsing (multipart) with default options:
var http = require('http'),
inspect = require('util').inspect;
var Busboy = require('busboy');
http.createServer(function(req, res) {
if (req.method === 'POST') {
var busboy = new Busboy({ headers: req.headers });
busboy.on('file', function(fieldname, file, filename, encoding, mimetype) {
console.log('File [' + fieldname + ']: filename: ' + filename + ', encoding: ' + encoding + ', mimetype: ' + mimetype);
file.on('data', function(data) {
console.log('File [' + fieldname + '] got ' + data.length + ' bytes');
});
file.on('end', function() {
console.log('File [' + fieldname + '] Finished');
});
});
busboy.on('field', function(fieldname, val, fieldnameTruncated, valTruncated, encoding, mimetype) {
console.log('Field [' + fieldname + ']: value: ' + inspect(val));
});
busboy.on('finish', function() {
console.log('Done parsing form!');
res.writeHead(303, { Connection: 'close', Location: '/' });
res.end();
});
req.pipe(busboy);
} else if (req.method === 'GET') {
res.writeHead(200, { Connection: 'close' });
res.end('<html><head></head><body>\
<form method="POST" enctype="multipart/form-data">\
<input type="text" name="textfield"><br />\
<input type="file" name="filefield"><br />\
<input type="submit">\
</form>\
</body></html>');
}
}).listen(8000, function() {
console.log('Listening for requests');
});
// Example output, using http://nodejs.org/images/ryan-speaker.jpg as the file:
//
// Listening for requests
// File [filefield]: filename: ryan-speaker.jpg, encoding: binary
// File [filefield] got 11971 bytes
// Field [textfield]: value: 'testing! :-)'
// File [filefield] Finished
// Done parsing form!
- Save all incoming files to disk:
var http = require('http'),
path = require('path'),
os = require('os'),
fs = require('fs');
var Busboy = require('busboy');
http.createServer(function(req, res) {
if (req.method === 'POST') {
var busboy = new Busboy({ headers: req.headers });
busboy.on('file', function(fieldname, file, filename, encoding, mimetype) {
var saveTo = path.join(os.tmpDir(), path.basename(fieldname));
file.pipe(fs.createWriteStream(saveTo));
});
busboy.on('finish', function() {
res.writeHead(200, { 'Connection': 'close' });
res.end("That's all folks!");
});
return req.pipe(busboy);
}
res.writeHead(404);
res.end();
}).listen(8000, function() {
console.log('Listening for requests');
});
- Parsing (urlencoded) with default options:
var http = require('http'),
inspect = require('util').inspect;
var Busboy = require('busboy');
http.createServer(function(req, res) {
if (req.method === 'POST') {
var busboy = new Busboy({ headers: req.headers });
busboy.on('file', function(fieldname, file, filename, encoding, mimetype) {
console.log('File [' + fieldname + ']: filename: ' + filename);
file.on('data', function(data) {
console.log('File [' + fieldname + '] got ' + data.length + ' bytes');
});
file.on('end', function() {
console.log('File [' + fieldname + '] Finished');
});
});
busboy.on('field', function(fieldname, val, fieldnameTruncated, valTruncated) {
console.log('Field [' + fieldname + ']: value: ' + inspect(val));
});
busboy.on('finish', function() {
console.log('Done parsing form!');
res.writeHead(303, { Connection: 'close', Location: '/' });
res.end();
});
req.pipe(busboy);
} else if (req.method === 'GET') {
res.writeHead(200, { Connection: 'close' });
res.end('<html><head></head><body>\
<form method="POST">\
<input type="text" name="textfield"><br />\
<select name="selectfield">\
<option value="1">1</option>\
<option value="10">10</option>\
<option value="100">100</option>\
<option value="9001">9001</option>\
</select><br />\
<input type="checkbox" name="checkfield">Node.js rules!<br />\
<input type="submit">\
</form>\
</body></html>');
}
}).listen(8000, function() {
console.log('Listening for requests');
});
// Example output:
//
// Listening for requests
// Field [textfield]: value: 'testing! :-)'
// Field [selectfield]: value: '9001'
// Field [checkfield]: value: 'on'
// Done parsing form!
API
Busboy is a Writable stream
Busboy (special) events
-
file(< string >fieldname, < ReadableStream >stream, < string >filename, < string >transferEncoding, < string >mimeType) - Emitted for each new file form field found.
transferEncodingcontains the 'Content-Transfer-Encoding' value for the file stream.mimeTypecontains the 'Content-Type' value for the file stream.- Note: if you listen for this event, you should always handle the
streamno matter if you care about the file contents or not (e.g. you can simply just dostream.resume();if you want to discard the contents), otherwise the 'finish' event will never fire on the Busboy instance. However, if you don't care about any incoming files, you can simply not listen for the 'file' event at all and any/all files will be automatically and safely discarded (these discarded files do still count towardsfilesandpartslimits). - If a configured file size limit was reached,
streamwill both have a boolean propertytruncated(best checked at the end of the stream) and emit a 'limit' event to notify you when this happens.
- Note: if you listen for this event, you should always handle the
-
field(< string >fieldname, < string >value, < boolean >fieldnameTruncated, < boolean >valueTruncated, < string >transferEncoding, < string >mimeType) - Emitted for each new non-file field found.
-
partsLimit() - Emitted when specified
partslimit has been reached. No more 'file' or 'field' events will be emitted. -
filesLimit() - Emitted when specified
fileslimit has been reached. No more 'file' events will be emitted. -
fieldsLimit() - Emitted when specified
fieldslimit has been reached. No more 'field' events will be emitted.
Busboy methods
-
(constructor)(< object >config) - Creates and returns a new Busboy instance.
-
The constructor takes the following valid
configsettings:-
headers - object - These are the HTTP headers of the incoming request, which are used by individual parsers.
-
highWaterMark - integer - highWaterMark to use for this Busboy instance (Default: WritableStream default).
-
fileHwm - integer - highWaterMark to use for file streams (Default: ReadableStream default).
-
defCharset - string - Default character set to use when one isn't defined (Default: 'utf8').
-
preservePath - boolean - If paths in the multipart 'filename' field shall be preserved. (Default: false).
-
limits - object - Various limits on incoming data. Valid properties are:
-
fieldNameSize - integer - Max field name size (in bytes) (Default: 100 bytes).
-
fieldSize - integer - Max field value size (in bytes) (Default: 1MB).
-
fields - integer - Max number of non-file fields (Default: Infinity).
-
fileSize - integer - For multipart forms, the max file size (in bytes) (Default: Infinity).
-
files - integer - For multipart forms, the max number of file fields (Default: Infinity).
-
parts - integer - For multipart forms, the max number of parts (fields + files) (Default: Infinity).
-
headerPairs - integer - For multipart forms, the max number of header key=>value pairs to parse Default: 2000 (same as node's http).
-
-
-
The constructor can throw errors:
-
Unsupported content type: $type - The
Content-Typeisn't one Busboy can parse. -
Missing Content-Type - The provided headers don't include
Content-Typeat all.
-
-