Question

I am developing a Google Chrome extension, and need to use the chrome.experimental.webRequest API. I have a simple background.html, which simple includes a script file. Currently, the script looks like this:

function listenBeforeRequest(args) {
  console.log(args);
};

chrome.experimental.webRequest.onBeforeRequest.addListener(listenBeforeRequest);

I have set a breakpoint on the addListener line, and it gets executed when the extension is loaded, and I get no errors. However, the listenBeforeRequest method never gets hit. My expectation would be that the function was called before each request.

How can I make this work ?

I am using Google Chrome 16 on Windows. I have set the experimental API flag in the browser under chrome://flags.

This is my manifest.json:

{
    "name": "extension",
    "version": "0.1",
    "description": "...",
    "background_page": "background.html",
    "browser_action": {
        "default_icon": "icon.png",
        "popup": "popup.html"
    },
    "permissions": ["background","webRequest","experimental", "*://*"]
}

Note, I also tried chrome.webRequest but that’s undefined – even though this page claims it has been added as a stable API: http://code.google.com/chrome/extensions/trunk/webRequest.html

What am I missing ? What do I need to do to get webRequest.onBeforeRequest event to work ?

Answer 1

Your permission match pattern lacks a path. Amend it to something like *://*/* or, alternatively, use the special pattern <all_urls>.