This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The Request interface of the Fetch API represents a resource request.
You can create a new Request object using the Request.Request() constructor, but you are more likely to encounter a Request object being returned as the result of another API operation, such as a service worker FetchEvent.request.
Request.Request()Request object.Request.method Read only
GET, POST, etc.)Request.url Read only
Request.headers Read only
Headers object of the request.Request.context Read only
audio, image, iframe, etc.)Request.referrer Read only
client).Request.referrerPolicy Read only
no-referrer).Request.mode Read only
cors, no-cors, same-origin, navigate.)Request.credentials Read only
omit, same-origin).Request.redirect Read only
follow, error, or manual.Request.integrity Read only
sha256-BpfBw7ivV8q2jLiT13fxDYAe2tJllusRSZ273h2nFSE=).Request.cache Read only
default, reload, no-cache).Request implements Body, so it also has the following property available to it:
Body.bodyUsed Read only
Boolean that declares whether the body has been used in a response yet.Request.clone()Request object.Request implements Body, so it also has the following methods available to it:
Body.arrayBuffer()ArrayBuffer representation of the request body.Body.blob()Blob representation of the request body.Body.formData()FormData representation of the request body.Body.json()JSON representation of the request body.Body.text()USVString (text) representation of the request body.Note: The Body functions can be run only once; next calls will resolve with empty strings/ArrayBuffers.
In the following snippet, we create a new request using the Request() constructor (for an image file in the same directory as the script), then return some property values of the request:
var myRequest = new Request('http://localhost/flowers.jpg');
var myURL = myRequest.url; // http://localhost/flowers.jpg
var myMethod = myRequest.method; // GET
var myCred = myRequest.credentials; // omit
You could then fetch this request by passing the Request object in as a parameter to a GlobalFetch.fetch() call, for example:
fetch(myRequest)
.then(function(response) {
return response.blob();
})
.then(function(response) {
var objectURL = URL.createObjectURL(response);
myImage.src = objectURL;
}); In the following snippet, we create a new request using the Request() constructor with some initial data and body content for an api request which need a body payload:
var myRequest = new Request('http://localhost/api', {method: 'POST', body: '{"foo":"bar"}'});
var myURL = myRequest.url; // http://localhost/api
var myMethod = myRequest.method; // POST
var myCred = myRequest.credentials; // omit
var bodyUsed = myRequest.bodyUsed; // true
Note: The body type can only be a Blob, BufferSource, FormData, URLSearchParams, USVString or ReadableStream type, so for adding a JSON object to the payload you need to stringify that object.
You could then fetch this api request by passing the Request object in as a parameter to a GlobalFetch.fetch() call, for example and get the response:
fetch(myRequest)
.then(function(response) {
if(response.status == 200) return response.json();
else throw new Error('Something went wrong on api server!');
})
.then(function(response) {
console.debug(response);
// ...
})
.catch(function(error) {
console.error(error);
}); | Specification | Status | Comment |
|---|---|---|
| Fetch The definition of 'Request' in that specification. | Living Standard | Initial definition |
| Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|---|
| Basic support | 42.0 | (Yes) |
39 (39) 34[1] | No support | 29 | No support |
Request.integrity | 45.0 | ? | No support | No support | ||
Request.redirect | 46.0 | ? |
| Feature | Android | Android Webview | Edge | Firefox Mobile (Gecko) | Firefox OS (Gecko) | IE Phone | Opera Mobile | Safari Mobile | Chrome for Android |
|---|---|---|---|---|---|---|---|---|---|
| Basic support | No support | No support | (Yes) | No support | No support | No support | No support | No support | 42.0 |
Request.integrity | No support | No support | ? | 45.0 | |||||
Request.redirect | No support | No support | ? | 46.0 |
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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