Gathering detailed insights and metrics for @fastify/busboy
Gathering detailed insights and metrics for @fastify/busboy
A streaming parser for HTML form data for node.js
Installations
npm install @fastify/busboyDeveloper Guide
BETA
Typescript
Yes
Module System
CommonJS
Node Version
22.12.0
NPM Version
10.9.0
Score
99.8
Supply Chain
100
Quality
85.3
Maintenance
100
Vulnerability
100
License
Releases
11
Languages
3
JavaScript
TypeScript
Batchfile
JavaScript (92.74%)
TypeScript (7.03%)
Batchfile (0.23%)
Developer
Download Statistics
Total Downloads
614,216,471
Last Day
1,826,512
Last Week
9,919,116
Last Month
41,289,508
Last Year
412,576,190
GitHub Statistics
MIT License
104 Stars
343 Commits
19 Forks
5 Watchers
2 Branches
41 Contributors
Updated on May 01, 2025
Bundle Size
23.70 kB
Minified
7.42 kB
Minified + Gzipped
Maintainers
18
Package Meta Information
Latest Version
3.1.1
Package Id
@fastify/busboy@3.1.1
Unpacked Size
78.25 kB
Size
19.77 kB
File Count
18
NPM Version
10.9.0
Node Version
22.12.0
Published on
Dec 22, 2024
Total Downloads
Cumulative downloads
Total Downloads
614,216,471
Last Day
37.4%
1,826,512
Compared to previous day
Last Week
5.2%
9,919,116
Compared to previous week
Last Month
1.1%
41,289,508
Compared to previous month
Last Year
136.4%
412,576,190
Compared to previous year
Weekly Downloads
Monthly Downloads
Yearly Downloads
Dev Dependencies
9
busboy
Description
A Node.js module for parsing incoming HTML form data.
This is an officially supported fork by fastify organization of the amazing library originally created by Brian White, aimed at addressing long-standing issues with it.
Benchmark (Mean time for 500 Kb payload, 2000 cycles, 1000 cycle warmup):
| Library | Version | Mean time in nanoseconds (less is better) |
|---|---|---|
| busboy | 0.3.1 | 340114 |
| @fastify/busboy | 1.0.0 | 270984 |
Changelog since busboy 0.31.
Requirements
- Node.js 10+
Install
npm i @fastify/busboy
Examples
- Parsing (multipart) with default options:
1const http = require('node:http'); 2const { inspect } = require('node:util'); 3const Busboy = require('@fastify/busboy'); 4 5http.createServer((req, res) => { 6 if (req.method === 'POST') { 7 const busboy = new Busboy({ headers: req.headers }); 8 busboy.on('file', (fieldname, file, filename, encoding, mimetype) => { 9 console.log(`File [${fieldname}]: filename: ${filename}, encoding: ${encoding}, mimetype: ${mimetype}`); 10 file.on('data', data => { 11 console.log(`File [${fieldname}] got ${data.length} bytes`); 12 }); 13 file.on('end', () => { 14 console.log(`File [${fieldname}] Finished`); 15 }); 16 }); 17 busboy.on('field', (fieldname, val, fieldnameTruncated, valTruncated, encoding, mimetype) => { 18 console.log(`Field [${fieldname}]: value: ${inspect(val)}`); 19 }); 20 busboy.on('finish', () => { 21 console.log('Done parsing form!'); 22 res.writeHead(303, { Connection: 'close', Location: '/' }); 23 res.end(); 24 }); 25 req.pipe(busboy); 26 } else if (req.method === 'GET') { 27 res.writeHead(200, { Connection: 'close' }); 28 res.end(`<html><head></head><body> 29 <form method="POST" enctype="multipart/form-data"> 30 <input type="text" name="textfield"><br> 31 <input type="file" name="filefield"><br> 32 <input type="submit"> 33 </form> 34 </body></html>`); 35 } 36}).listen(8000, () => { 37 console.log('Listening for requests'); 38}); 39 40// Example output, using http://nodejs.org/images/ryan-speaker.jpg as the file: 41// 42// Listening for requests 43// File [filefield]: filename: ryan-speaker.jpg, encoding: binary 44// File [filefield] got 11971 bytes 45// Field [textfield]: value: 'testing! :-)' 46// File [filefield] Finished 47// Done parsing form!
- Save all incoming files to disk:
1const http = require('node:http'); 2const path = require('node:path'); 3const os = require('node:os'); 4const fs = require('node:fs'); 5 6const Busboy = require('@fastify/busboy'); 7 8http.createServer(function(req, res) { 9 if (req.method === 'POST') { 10 const busboy = new Busboy({ headers: req.headers }); 11 busboy.on('file', function(fieldname, file, filename, encoding, mimetype) { 12 var saveTo = path.join(os.tmpdir(), path.basename(fieldname)); 13 file.pipe(fs.createWriteStream(saveTo)); 14 }); 15 busboy.on('finish', function() { 16 res.writeHead(200, { 'Connection': 'close' }); 17 res.end("That's all folks!"); 18 }); 19 return req.pipe(busboy); 20 } 21 res.writeHead(404); 22 res.end(); 23}).listen(8000, function() { 24 console.log('Listening for requests'); 25});
- Parsing (urlencoded) with default options:
1const http = require('node:http'); 2const { inspect } = require('node:util'); 3 4const Busboy = require('@fastify/busboy'); 5 6http.createServer(function(req, res) { 7 if (req.method === 'POST') { 8 const busboy = new Busboy({ headers: req.headers }); 9 busboy.on('file', function(fieldname, file, filename, encoding, mimetype) { 10 console.log('File [' + fieldname + ']: filename: ' + filename); 11 file.on('data', function(data) { 12 console.log('File [' + fieldname + '] got ' + data.length + ' bytes'); 13 }); 14 file.on('end', function() { 15 console.log('File [' + fieldname + '] Finished'); 16 }); 17 }); 18 busboy.on('field', function(fieldname, val, fieldnameTruncated, valTruncated) { 19 console.log('Field [' + fieldname + ']: value: ' + inspect(val)); 20 }); 21 busboy.on('finish', function() { 22 console.log('Done parsing form!'); 23 res.writeHead(303, { Connection: 'close', Location: '/' }); 24 res.end(); 25 }); 26 req.pipe(busboy); 27 } else if (req.method === 'GET') { 28 res.writeHead(200, { Connection: 'close' }); 29 res.end('<html><head></head><body>\ 30 <form method="POST">\ 31 <input type="text" name="textfield"><br />\ 32 <select name="selectfield">\ 33 <option value="1">1</option>\ 34 <option value="10">10</option>\ 35 <option value="100">100</option>\ 36 <option value="9001">9001</option>\ 37 </select><br />\ 38 <input type="checkbox" name="checkfield">Node.js rules!<br />\ 39 <input type="submit">\ 40 </form>\ 41 </body></html>'); 42 } 43}).listen(8000, function() { 44 console.log('Listening for requests'); 45}); 46 47// Example output: 48// 49// Listening for requests 50// Field [textfield]: value: 'testing! :-)' 51// Field [selectfield]: value: '9001' 52// Field [checkfield]: value: 'on' 53// 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. - The property
bytesReadinforms about the number of bytes that have been read so far.
- 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.
-
autoDestroy - boolean - Whether this stream should automatically call .destroy() on itself after ending. (Default: false).
-
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).
-
isPartAFile - function - Use this function to override the default file detection functionality. It has following parameters:
-
fieldName - string The name of the field.
-
contentType - string The content-type of the part, e.g.
text/plain,image/jpeg,application/octet-stream -
fileName - string The name of a file supplied by the part.
(Default:
(fieldName, contentType, fileName) => (contentType === 'application/octet-stream' || fileName !== undefined)) -
-
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: 1 MiB, which is 1024 x 1024 bytes).
-
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
-
headerSize - integer - For multipart forms, the max size of a multipart header Default: 81920.
-
-
-
The constructor can throw errors:
-
Busboy expected an options-Object. - Busboy expected an Object as first parameters.
-
Busboy expected an options-Object with headers-attribute. - The first parameter is lacking of a headers-attribute.
-
Limit $limit is not a valid number - Busboy expected the desired limit to be of type number. Busboy throws this Error to prevent a potential security issue by falling silently back to the Busboy-defaults. Potential source for this Error can be the direct use of environment variables without transforming them to the type number.
-
Unsupported Content-Type. - The
Content-Typeisn't one Busboy can parse. -
Missing Content-Type-header. - The provided headers don't include
Content-Typeat all.
-
-
No vulnerabilities found.
No security vulnerabilities found.