I was looking for an solution to make an XHR request to a server from a local html file and found a solution using Chrome and PHP. (no Jquery)
Javascripts:
var x = new XMLHttpRequest();
if(x) x.onreadystatechange=function(){
if (x.readyState === 4 && x.status===200){
console.log(x.responseText); //Success
}else{
console.log(x); //Failed
}
};
x.open(GET, 'http://example.com/', true);
x.withCredentials = true;
x.send();
My Chrome's request header Origin: null
My PHP response header (Note that 'null' is a string). HTTP_REFERER allow cross-origin from a remote server to another.
header('Access-Control-Allow-Origin: '.(trim($_SERVER['HTTP_REFERER'],'/')?:'null'),true);
header('Access-Control-Allow-Credentials:true',true);
I was able to successfully connect to my server.
You can disregards the Credentials headers, but this works for me with Apache's AuthType Basic enabled
I tested compatibility with FF and Opera, It works in many cases such as:
From a VM LAN IP (192.168.0.x) back to the VM'S WAN (public) IP:port
From a VM LAN IP back to a remote server domain name.
From a local .HTML file to the VM LAN IP and/or VM WAN IP:port,
From a local .HTML file to a remote server domain name.
And so on.