javascript - how Postman send requests? ajax, same origin policy

Question

I have found this very useful Chrome extension called Postman. This is a very useful extension especially when you are into programming RESTful applications.

One thing I am confused on is that how this plugin/extension able to send POST request successfully on different domains?

I tried voting in a poll using Postman like this.

After submitting that, the vote was actually counted in, but when I tried doing that using AJAX and JavaScript, it fails, because of different origin policy of browsers.

How is that even possible?

Here is my code using jQuery. I used that in my computer though, localhost.

init: function() {
    $.ajax({
        url: 'http://example.com/vote.php',
        type:'POST',
        dataType: 'html',
        data: {
            id: '1'
        },
        success: function(data) {
        if ( data == 'voted' ) {
            $('.set-result').html( 'you already voted. try again after 24 hours' );
        } else {
            $('.set-result').html( 'successfully voted' );
        }
    }
    });
},

Answer 1

Chrome packaged apps can have cross domain permissions. When you install Postman it promts you that this app will access any domain.

By placing */* in permissions section of your manifest file, you can do this.

Read more here: https://developer.chrome.com/extensions/xhr.html