Question

This is my first time ever touching any sort of client sided web programming language, and, I’m attempting to make my first chrome addon. Basically what I want to do is code something which redirects from:-

ABC.com/ID

to

A.ABC.com/ID

So far I have it all coded, however, what it does is it loads ABC.com/ID, waits for it to complete, then injects my content script and re-loads A.ABC.com/ID. This is obviously a huge waste of time. Is there any way I can tell chrome to load this script either before the DNS lookup (Because that’s useless, because it’s on a new subdomain), or, before opening a connection to the site (Because this isn’t the page we’re looking for)? I understand a content script may not be the best idea, if it’s not, then what would be?

Answer 1

Yes, you can achieve with web request API without any content scripts. The following demonstration blocks all Facebook URL’s and redirects them to Google, similarly use ABC.com/ID instead of Facebook and use A.ABC.com/ID instead of Google for this use case.

References

• Web request
• Background Page
• Manifest File

manifest.json

Ensure all permissions are available and register background page with extension.

{
  "name": "Hanlder for Navigation",
  "description": "http://stackoverflow.com/questions/14050467",
  "version": "1",
  "manifest_version": 2,
  "background": {
    "scripts": ["background.js"]
  },
  "permissions":["https://www.facebook.com/*","webRequest","webRequestBlocking"]
}

background.js

This code blocks all URL request to Facebook and redirects them to Google.

// Register an event listener which 
//traces all requests before being fired
chrome.webRequest.onBeforeRequest.addListener(function (details) {
    return {
        redirectUrl: "http://www.google.co.in/" /*Redirection URL*/
    };
}, {
    urls: ["*://www.facebook.com/*"] /* List of URL's */
}, ["blocking"]); // Block intercepted requests until this handler has finished

Output

All request(s) to Facebook are redirected to Google.