jshttp
accepts
Higher level content negotiation based on negotiator. Extracted from koa for general use.
In addition to negotiator, it allows:
- Allows types as an array or arguments list, ie
(['text/html', 'application/json'])as well as('text/html', 'application/json'). - Allows type shorthands such as
json. - Returns
falsewhen no types match - Treats non-existent headers as
*
Installation
This is a Node.js module available through the
npm registry. Installation is done using the
npm install command:
$ npm install acceptsAPI
var accepts = require('accepts')accepts(req)
Create a new Accepts object for the given req.
.charset(charsets)
Return the first accepted charset. If nothing in charsets is accepted,
then false is returned.
.charsets()
Return the charsets that the request accepts, in the order of the client's preference (most preferred first).
.encoding(encodings)
Return the first accepted encoding. If nothing in encodings is accepted,
then false is returned.
.encodings()
Return the encodings that the request accepts, in the order of the client's preference (most preferred first).
.language(languages)
Return the first accepted language. If nothing in languages is accepted,
then false is returned.
.languages()
Return the languages that the request accepts, in the order of the client's preference (most preferred first).
.type(types)
Return the first accepted type (and it is returned as the same text as what
appears in the types array). If nothing in types is accepted, then false
is returned.
The types array can contain full MIME types or file extensions. Any value
that is not a full MIME types is passed to require('mime-types').lookup.
.types()
Return the types that the request accepts, in the order of the client's preference (most preferred first).
Examples
Simple type negotiation
This simple example shows how to use accepts to return a different typed
respond body based on what the client wants to accept. The server lists it's
preferences in order and will get back the best match between the client and
server.
var accepts = require('accepts')
var http = require('http')
function app (req, res) {
var accept = accepts(req)
// the order of this list is significant; should be server preferred order
switch (accept.type(['json', 'html'])) {
case 'json':
res.setHeader('Content-Type', 'application/json')
res.write('{"hello":"world!"}')
break
case 'html':
res.setHeader('Content-Type', 'text/html')
res.write('<b>hello, world!</b>')
break
default:
// the fallback is text/plain, so no need to specify it above
res.setHeader('Content-Type', 'text/plain')
res.write('hello, world!')
break
}
res.end()
}
http.createServer(app).listen(3000)You can test this out with the cURL program:
curl -I -H'Accept: text/html' http://localhost:3000/