then-busboy

then-busboy

Promise-based wrapper around Busboy. Process multipart/form-data content and returns it as a single object.

Note: The current documentation is for 2.x versions of then-busboy. If you're looking for a previous version, check out the 1.x branch.

Installation

Use can install then-busboy from npm:

npm install --save then-busboy

Or with yarn:

yarn add then-busboy

API

busboy(request[, options]) -> Promise<Object>

• http.IncomingMessage request – HTTP request object
• object options
  • boolean restoreTypes – allow to restore type of each value (default – true)
  • more information about busboy options here.

constructor File(options)

• object options – an object that contains the following information about file:
  • stream.Readable contents – the content of the file.
  • string filename – name of the file (with an extension)
  • string env – encoding of the file content
  • string mime – file mime type

Instance properties

contents

A file contents Readable stream.

stream

An alias for contents

filename

A full name of the file

basename

A name of the file without extension

extname

A file extension

mime

A file mime type

enc

File contents encoding

path

Default path of the file

Instance methods

read() => Promise<Buffer>

Read a file from contents stream.

write([path]) => Promise<void>

Write a file content to disk. Optionally you can set a custom path.

• string path – a path where File content should be saved. (default – File#path)

By default, file will be saved in system temporary directory os.tmpdir(). You can take this path from path property.

Fields format

then-busboy can restore an object structure from form-data field names if you will follow the special naming format with bracket notation:

# Note that the following example is just a pseudo code
rootField[nestedField] = "I beat Twilight Sparkle and all I got was this lousy t-shirt"

then-busboy will return the this object for an example from above:

{
  rootField: {
    nestedField: "I beat Twilight Sparkle and all I got was this lousy t-shirt"
  }
}

You can also send an arrays and collections using bracket format:

message[sender] = "John Doe"
message[text] = "Some whatever text message."
message[attachments][0][file] = <here is the file content>
message[attachments][0][description] = "Here is a description of the file"

then-busboy returns the following object:

{
  message: {
    sender: "John Doe",
    text: "Some whatever text message.",
    attachments: [
      {
        file: File, // this field will be represended as a File instance
        description: "Here is a description of the file"
      }
    ]
  }
}

Note that there is no an implementation for array as root field for now!

Usage

Just import then-busboy and pass request object as first argument.

import busboy from "then-busboy"
import {createServer} from "http"

function handler(req, res) {
  // Get result from then-busboy
  function onFulfilled(data) {
    res.writeHead("Content-Type", "application/json")
    res.end(JSON.stringify(data))
  }

  // Handle errors
  function onRejected(err) {
    res.statusCode = err.status || 500
    res.end(String(err))
  }

  // Call `then-busboy` with `req`
  busboy(req).then(onFulfilled, onRejected)
}

createServer(handler)
  .listen(2319, () => console.log("Server started on http://localhost:2319"))

then-busboy always returns a Promise, so you can use it with asynchronous function syntax:

// Some of your awesome code with async workflow...
const data = await busboy(req)

License

MIT