Infer the content-type of a request.
This is a Node.js module available through the
npm registry. Installation is done using the
npm install command:
$ npm install type-isvar http = require('http')
var typeis = require('type-is')
http.createServer(function (req, res) {
var istext = typeis(req, ['text/*'])
res.end('you ' + (istext ? 'sent' : 'did not send') + ' me text')
})request is the node HTTP request. types is an array of types.
// req.headers.content-type = 'application/json'
typeis(req, ['json']) // 'json'
typeis(req, ['html', 'json']) // 'json'
typeis(req, ['application/*']) // 'application/json'
typeis(req, ['application/json']) // 'application/json'
typeis(req, ['html']) // falseReturns a Boolean if the given request has a body, regardless of the
Content-Type header.
Having a body has no relation to how large the body is (it may be 0 bytes). This is similar to how file existence works. If a body does exist, then this indicates that there is data to read from the Node.js request stream.
if (typeis.hasBody(req)) {
// read the body, since there is one
req.on('data', function (chunk) {
// ...
})
}mediaType is the media type string. types is an array of types.
var mediaType = 'application/json'
typeis.is(mediaType, ['json']) // 'json'
typeis.is(mediaType, ['html', 'json']) // 'json'
typeis.is(mediaType, ['application/*']) // 'application/json'
typeis.is(mediaType, ['application/json']) // 'application/json'
typeis.is(mediaType, ['html']) // false- 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
*/*or*/jsonorapplication/*. The full mime type will be returned if matched. - A suffix such as
+json. This can be combined with a wildcard such as*/vnd+jsonorapplication/*+json. The full mime type will be returned if matched.
false will be returned if no type matches or the content type is invalid.
null will be returned if the request does not have a body.
var express = require('express')
var typeis = require('type-is')
var app = express()
app.use(function bodyParser (req, res, next) {
if (!typeis.hasBody(req)) {
return next()
}
switch (typeis(req, ['urlencoded', 'json', 'multipart'])) {
case 'urlencoded':
// parse urlencoded body
throw new Error('implement urlencoded body parsing')
case 'json':
// parse json body
throw new Error('implement json body parsing')
case 'multipart':
// parse multipart body
throw new Error('implement multipart body parsing')
default:
// 415 error code
res.statusCode = 415
res.end()
break
}
})
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent