| # busboy |
| |
| <div align="center"> |
| |
| [](https://github.com/fastify/busboy/actions) |
| [](https://coveralls.io/r/fastify/busboy?branch=master) |
| [](https://standardjs.com/) |
| [](https://github.com/nodejs/security-wg/blob/HEAD/processes/responsible_disclosure_template.md) |
| |
| </div> |
| |
| <div align="center"> |
| |
| [](https://www.npmjs.com/package/@fastify/busboy) |
| [](https://www.npmjs.com/package/@fastify/busboy) |
| |
| </div> |
| |
| Description |
| =========== |
| |
| A Node.js module for parsing incoming HTML form data. |
| |
| This is an officially supported fork by [fastify](https://github.com/fastify/) organization of the amazing library [originally created](https://github.com/mscdex/busboy) 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](https://github.com/fastify/busboy/blob/master/CHANGELOG.md) since busboy 0.31. |
| |
| Requirements |
| ============ |
| |
| * [Node.js](http://nodejs.org/) 10+ |
| |
| |
| Install |
| ======= |
| |
| npm i @fastify/busboy |
| |
| |
| Examples |
| ======== |
| |
| * Parsing (multipart) with default options: |
| |
| ```javascript |
| const http = require('node:http'); |
| const { inspect } = require('node:util'); |
| const Busboy = require('busboy'); |
| |
| http.createServer((req, res) => { |
| if (req.method === 'POST') { |
| const busboy = new Busboy({ headers: req.headers }); |
| busboy.on('file', (fieldname, file, filename, encoding, mimetype) => { |
| console.log(`File [${fieldname}]: filename: ${filename}, encoding: ${encoding}, mimetype: ${mimetype}`); |
| file.on('data', data => { |
| console.log(`File [${fieldname}] got ${data.length} bytes`); |
| }); |
| file.on('end', () => { |
| console.log(`File [${fieldname}] Finished`); |
| }); |
| }); |
| busboy.on('field', (fieldname, val, fieldnameTruncated, valTruncated, encoding, mimetype) => { |
| console.log(`Field [${fieldname}]: value: ${inspect(val)}`); |
| }); |
| busboy.on('finish', () => { |
| 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, () => { |
| 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: |
| |
| ```javascript |
| const http = require('node:http'); |
| const path = require('node:path'); |
| const os = require('node:os'); |
| const fs = require('node:fs'); |
| |
| const Busboy = require('busboy'); |
| |
| http.createServer(function(req, res) { |
| if (req.method === 'POST') { |
| const 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: |
| |
| ```javascript |
| const http = require('node:http'); |
| const { inspect } = require('node:util'); |
| |
| const Busboy = require('busboy'); |
| |
| http.createServer(function(req, res) { |
| if (req.method === 'POST') { |
| const 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. `transferEncoding` contains the 'Content-Transfer-Encoding' value for the file stream. `mimeType` contains the 'Content-Type' value for the file stream. |
| * Note: if you listen for this event, you should always handle the `stream` no matter if you care about the file contents or not (e.g. you can simply just do `stream.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 towards `files` and `parts` limits). |
| * If a configured file size limit was reached, `stream` will both have a boolean property `truncated` (best checked at the end of the stream) and emit a 'limit' event to notify you when this happens. |
| * The property `bytesRead` informs about the number of bytes that have been read so far. |
| |
| * **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 `parts` limit has been reached. No more 'file' or 'field' events will be emitted. |
| |
| * **filesLimit**() - Emitted when specified `files` limit has been reached. No more 'file' events will be emitted. |
| |
| * **fieldsLimit**() - Emitted when specified `fields` limit 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 `config` settings: |
| |
| * **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-Type` isn't one Busboy can parse. |
| |
| * **Missing Content-Type-header.** - The provided headers don't include `Content-Type` at all. |
