type-is

type-is

Infer the content-type of a request.

Install

$ npm install type-is

API

var http = require('http')
var is   = require('type-is')

http.createServer(function (req, res) {
  var istext = is(req, ['text/*'])
  res.end('you ' + (istext ? 'sent' : 'did not send') + ' me text')
})

type = is(request, types)

request is the node HTTP request. types is an array of types.

// req.headers.content-type = 'application/json'

is(req, ['json'])             // 'json'
is(req, ['html', 'json'])     // 'json'
is(req, ['application/*'])    // 'application/json'
is(req, ['application/json']) // 'application/json'

is(req, ['html']) // false

type = is.is(mediaType, types)

mediaType is the media type string. types is an array of types.

var mediaType = 'application/json'

is.is(mediaType, ['json'])             // 'json'
is.is(mediaType, ['html', 'json'])     // 'json'
is.is(mediaType, ['application/*'])    // 'application/json'
is.is(mediaType, ['application/json']) // 'application/json'

is.is(mediaType, ['html']) // false

Each type can be:

• An extension name such as json. This name will be returned if matched.
• A mime type such as application/json.
• A mime type with a wildcard such as */json or application/*. The full mime type will be returned if matched
• A suffix such as +json. This can be combined with a wildcard such as */vnd+json or application/*+json. The full mime type will be returned if matched.

false will be returned if no type matches.

null will be returned if the request does not have a body.

Examples

Example body parser

var is = require('type-is');

function bodyParser(req, res, next) {
  if (!is.hasBody(req)) {
    return next()
  }

  switch (is(req, ['urlencoded', 'json', 'multipart'])) {
    case 'urlencoded':
      // parse urlencoded body
      throw new Error('implement urlencoded body parsing')
      break
    case 'json':
      // parse json body
      throw new Error('implement json body parsing')
      break
    case 'multipart':
      // parse multipart body
      throw new Error('implement multipart body parsing')
      break
    default:
      // 415 error code
      res.statusCode = 415
      res.end()
      return
  }
}

License

MIT

Similar packages

Other packages similar to type-is

mime-types

The mime-types package is similar to type-is in that it provides functionality for looking up MIME types based on file extensions and vice versa. However, it does not directly deal with request objects and is more focused on the mapping between MIME types and file extensions.

content-type

The content-type package is used to parse and format 'Content-Type' headers. Unlike type-is, it does not provide methods to check if a request or response matches a specific content type, but it can be used to construct and deconstruct 'Content-Type' headers.

accepts

The accepts package is designed to deal with the HTTP Accept header, allowing servers to negotiate content type with clients. It is similar to type-is in that it helps determine the type of content, but it focuses on what the client can accept, rather than what the server is receiving or sending.