The Request()
constructor creates a new Request
object.
var myRequest = new Request(input[, init]);
USVString
containing the direct URL of the resource you want to fetch.Request
object, effectively creating a copy. Note the following behavioural updates to retain security while making the constructor less likely to throw exceptions: Request.referrer
is stripped out.Request.mode
of navigate
, the mode
value is converted to same-origin
.method
: The request method, e.g., GET
, POST
.headers
: Any headers you want to add to your request, contained within a Headers
object or an object literal with ByteString
values.body
: Any body that you want to add to your request: this can be a Blob
, BufferSource
, FormData
, URLSearchParams
, USVString
, or ReadableStream
object. Note that a request using the GET
or HEAD
method cannot have a body.mode
: The mode you want to use for the request, e.g., cors
, no-cors
, same-origin
, or navigate
. The default is cors
. In Chrome the default is no-cors
before Chrome 47 and same-origin
starting with Chrome 47.credentials
: The request credentials you want to use for the request: omit
, same-origin
, or include
. The default is omit
. In Chrome the default is same-origin
before Chrome 47 and include
starting with Chrome 47.cache
: The cache mode you want to use for the request.redirect
: The redirect mode to use: follow
, error
, or manual
. In Chrome the default is follow
(before Chrome 47 it defaulted to manual
).referrer
: A USVString
specifying no-referrer
, client
, or a URL. The default is client
.integrity
: Contains the subresource integrity value of the request (e.g., sha256-BpfBw7ivV8q2jLiT13fxDYAe2tJllusRSZ273h2nFSE=
).Type | Description |
---|---|
TypeError | Since Firefox 43, Request() will throw a TypeError if the URL has credentials, such as http://user:[email protected]. |
In our Fetch Request example (see Fetch Request live) we create a new Request
object using the constructor, then fetch it using a GlobalFetch.fetch
call. Since we are fetching an image, we run Body.blob
on the response to give it the proper MIME type so it will be handled properly, then create an Object URL of it and display it in an <img>
element.
var myImage = document.querySelector('img'); var myRequest = new Request('flowers.jpg'); fetch(myRequest).then(function(response) { return response.blob(); }).then(function(response) { var objectURL = URL.createObjectURL(response); myImage.src = objectURL; });
In our Fetch Request with init example (see Fetch Request init live) we do the same thing except that we pass in an init object when we invoke fetch()
:
var myImage = document.querySelector('img'); var myHeaders = new Headers(); myHeaders.append('Content-Type', 'image/jpeg'); var myInit = { method: 'GET', headers: myHeaders, mode: 'cors', cache: 'default' }; var myRequest = new Request('flowers.jpg',myInit); fetch(myRequest).then(function(response) { ... });
Note that you could also pass the init object into the fetch
call to get the same effect, e.g.:
fetch(myRequest,myInit).then(function(response) { ... });
You can also use an object literal as headers
in init
.
var myInit = { method: 'GET', headers: { 'Content-Type': 'image/jpeg' }, mode: 'cors', cache: 'default' }; var myRequest = new Request('flowers.jpg', myInit);
You may also pass a Request
object to the Request()
constructor to create a copy of the Request (This is similar to calling the clone()
method.)
var copy = new Request(myRequest);
Note: This last usage is probably only useful in ServiceWorkers.
Specification | Status | Comment |
---|---|---|
Fetch The definition of 'Request()' in that specification. | Living Standard |
Desktop | ||||||
---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | |
Basic support | 42
|
15 | 39
|
No | 29
|
10.1 |
Consume response body as a ReadableStream
|
43 | ? | Yes
|
? | ? | No |
Send ReadableStream in request body
|
No | ? | No | ? | ? | No |
navigate mode
|
49 | 15 | 46 | No | Yes | 10.1 |
referrer init option
|
? | 15 | 47 | No | Yes | 10.1 |
cross-origin referrer stripped out and navigate mode converted to same-origin when constructor created from existing Request object.
|
Yes | 15 | 54 | No | Yes | 10.1 |
Mobile | |||||||
---|---|---|---|---|---|---|---|
Android webview | Chrome for Android | Edge Mobile | Firefox for Android | Opera for Android | iOS Safari | Samsung Internet | |
Basic support | 42
|
42
|
Yes | Yes | No | 10.3 | 4.0
|
Consume response body as a ReadableStream
|
43 | 43 | ? | Yes
|
? | 10.3 | 4.0 |
Send ReadableStream in request body
|
No | No | ? | No | ? | No | No |
navigate mode
|
No | 49 | 15 | Yes | No | 10.3 | 5.0 |
referrer init option
|
Yes | Yes | ? | Yes | ? | 10.3 | Yes |
cross-origin referrer stripped out and navigate mode converted to same-origin when constructor created from existing Request object.
|
Yes | Yes | 15 | Yes | ? | 10.3 | Yes |
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/Request/Request