javascript / ajax question

Question

I'm wondering if anyone knows a javascript library where I could remotely login to a site, then browse pages upon logging in.

This is very easy with php's curl but I'm wondering if there is a javascript equivalent where I can execute multiple remote url's under a single http session.

Basically what I'm looking to do is post a username/password to one of my sites and then immediately post some other commands to a different url (same remote domain) using the authenticated session.

I haven't come across anything like this yet so I'm wondering if anyone can point me in the direction (if it's even possible). Can definitely be HTML5.

Answer 1

Due to same origin policy restrictions in browsers this is not possible using javascript. You need a server side script that will act as a bridge between your site and the remote sites. Then talk to this local script using AJAX.

Answer 2

There are some techniques available to bypass the same origin policy:

If you don't need to read the response of your POST calls, you can create a FORM by javascript with an action to any url (not limited to the same origin policy) like in this question: How do I send a cross-domain POST request via JavaScript?

But this means you rely only on session cookies for the security, this is open for XSS attacks.

As you own the other domain site, you could develop a small service that returns a JSON with the data you need, and use the JSONP technique, eg:

<script src="http://otherdomain/curl?url=page.html&callback=cb">
</script>

May be you could signin before using the POST technique above and sending a secret token that you reuse in the url to improve the security.

And finally there is a way to act/read on other pages using a bookmarklet.
The idea is to inject in the other domain's page a script that can run with all the privileges, and send back information to your domain.
But this requires a manual action (click a link or a browser bookmark)