Add-ons

webRequest.StreamFilter.write()

Writes some response data to the output stream.
 
You can only call this function after the onstart event has fired.
 

Syntax

filter.write(
  data    // ArrayBuffer or Uint8Array
)

Parameters

data
Uint8Array or ArrayBuffer: array of bytes containing the data to pass to the browser's rendering engine.

Return value

None.

Browser compatibility

ChromeEdgeFirefoxFirefox for AndroidOpera
Basic support No No5757 No

Examples

This example uses write() to replace "Example" in the response with "WebExtension Example".

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"]
);

Document Tags and Contributors

 Contributors to this page: wbamberg
 Last updated by: wbamberg,