Use this function to create a webRequest.StreamFilter
object for a particular request. You can then use the stream filter to monitor and modify the response. You'd typically call this function from a webRequest
event listener.
To use this API you must have the "webRequestBlocking" API permission, as well as the normal permissions needed for the event listener (the "webRequest" permission and the host permission for the host).
Syntax
var filter = browser.webRequest.filterResponseData( requestId // string )
Parameters
requestId
string
. ID of the request to filter. You can get this from thedetails
object that is passed into anywebRequest
event listeners.
Return value
A webRequest.StreamFilter
object that you can use to monitor and modify the response.
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Chrome | Edge | Firefox | Firefox for Android | Opera | |
---|---|---|---|---|---|
Basic support | No | No | 57 | 57 | No |
Examples
This example, taken from the http-response example extension, creates a filter in webRequest.onBeforeRequest
and uses it to modify the response:
function listener(details) { let filter = browser.webRequest.filterResponseData(details.requestId); let decoder = new TextDecoder("utf-8"); let encoder = new TextEncoder(); filter.ondata = event => { let str = decoder.decode(event.data, {stream: true}); // Just change any instance of Example in the HTTP response // to WebExtension Example. str = str.replace(/Example/g, 'WebExtension Example'); filter.write(encoder.encode(str)); filter.disconnect(); } return {}; } browser.webRequest.onBeforeRequest.addListener( listener, {urls: ["https://example.com/*"], types: ["main_frame"]}, ["blocking"] );