Google Chrome Extension Http request

Question

I'd like to know if Google Chrome Extension can make a HTTP request and parse the body of the result (like Curl). For example, there is a server 1.2.3.4 that answers the question ?a=1&b=2 by summarizing the URL parameters. The query "http://1.2.3.4?a=1&b=2" would return a body containing 3, and my extension wants to submit such a query and parse the result.

Any help would be appreciated.

Answer 1

Yes, using Cross-Origin XMLHttpRequest.

1. Set the permissions in manifest.json

2. Then use it like this in your extension page:

   var xhr = new XMLHttpRequest();
   xhr.open("GET", "http://api.example.com/data.json", true);
   xhr.onreadystatechange = function() {
     if (xhr.readyState == 4) {
       // WARNING! Might be injecting a malicious script!
       document.getElementById("resp").innerHTML = xhr.responseText;
       ...
     }
   }
   xhr.send();
   

Notes:

• Content scripts can't make cross-origin requests in modern Chrome, more info.
• ManifestV3 background script doesn't have XMLHttpRequest so you will use fetch there.