Accessing blob object through a blob URL

Question

I want to access the blob object from a blob url (url that starts with "blob:https/example.com") in c++ only.

This below is the implementation in JS that I want to imitate in c++:

if (url && url.startsWith('blob:')) {
      const fetchblobURL = async function (node, value) {
        let blob = await fetch(value).then(r => r.blob()).then(blob => {
          const reader = new FileReader();
          reader.readAsDataURL(blob);
        });
      }
      fetchblobURL(node, attrName, attrValue);
}

Any ideas on the implementation using native c++ or libraries will be appreciated. Thank you.