how to bypass Access-Control-Allow-Origin?

Question

I'm doing a ajax call to my own server on a platform which they set prevent these ajax calls (but I need it to fetch the data from my server to display retrieved data from my server's database). My ajax script is working , it can send the data over to my server's php script to allow it to process. However it cannot get the processed data back as it is blocked by "Access-Control-Allow-Origin"

I have no access to that platform's source/core. so I can't remove the script that it disallowing me to do so. (P/S I used Google Chrome's Console and found out this error)

The Ajax code as shown below:

 $.ajax({
     type: "GET",
     url: "http://example.com/retrieve.php",
     data: "id=" + id + "&url=" + url,
     dataType: 'json',   
     cache: false,
     success: function(data)
      {
        var friend = data[1];              
        var blog = data[2];           
        $('#user').html("<b>Friends: </b>"+friend+"<b><br> Blogs: </b>"+blog);

      } 
  });

or is there a JSON equivalent code to the ajax script above ? I think JSON is allowed.

I hope someone could help me out.

Answer 1

Put this on top of retrieve.php:

header('Access-Control-Allow-Origin: *');  

Note that this effectively disables CORS protection, and leaves your users exposed to attack. If you're not completely certain that you need to allow all origins, you should lock this down to a more specific origin:

header('Access-Control-Allow-Origin: https://www.example.com')

Please refer to following stack answer for better understanding of Access-Control-Allow-Origin

https://stackoverflow.com/a/10636765/413670