Set cookie on multiple domains with PHP or JavaScript

Question 1

I have 3 domains that are themed the same. If somebody chooses a different theme, I want it to propagate across all 3 domains so their experience stays the same.

I was planning to accomplish this by setting a cookie on domain1, redirect to domain2 where the cookie is set, redirect to domain3 where the cookie is set, redirect back. Since the information doesn't need to be secure or protected, this will work fine with no real problems.

I hate the idea 3 redirects just to set a cookie on each domain and was looking for something a little more elegant.

Question 2

Do what Google is doing. Yes, Google is doing this same trick to login the user to YouTube and other Google services which are on different domains.

Create a PHP file that sets the cookie on all 3 domains. Then on the domain where the theme is going to set, create a HTML file that would load the PHP file that sets cookie on the other 2 domains. Example:

<html>
   <head></head>
   <body>
      <p>Please wait.....</p>
      <img src="http://domain2.com/setcookie.php?theme=whateveryourthemehere" />
      <img src="http://domain3.com/setcookie.php?theme=whateveryourthemehere" />
   </body>
</html>

Then add an onload callback on body tag. The document will only load when the images completely load that is when cookies are set on the other 2 domains. Onload Callback :

<head>
   <script>
   function loadComplete(){
      window.location="http://domain1.com";//URL of domain1
   }
   </script>
</head>
<body onload="loadComplete()">

setcookie.php

We set the cookies on the other domains using a PHP file like this :

<?php
if(isset($_GET['theme'])){
   setcookie("theme", $_GET['theme'], time()+3600);
}
?>

Now cookies are set on the three domains.

Source - My Blog

Question 3

When you set a cookie, you can set various options. Cookies, as everyone knows, can only be accessed by scripts on the same domain, but you can also affect what path the cookie is set on. For instance, a cookie set on /foo/bar.php may not be accessible on /foobar.php.

PHP by default sets the cookie to the current path. So, with the above example, the cookie is set to the path /foo/, and is not accessible outside that path.

When you set your cookies, therefore, it's best to be explicit about where you want them to be available. In PHP this is very easy; just set an extra parameter specifying the path. As you indicate in the comments, you need the most liberal path possible /, which means "anywhere on this domain".

setcookie('cad', 'somevalue', 0, '/');

See the setcookie documentation in the PHP manual.

Question 4

<?php
$cookie_name = "test";
$cookie_value = "123";
setcookie($cookie_name, $cookie_value, time() + (86400 * 30), "/"); // 86400 = 1 day
?>

You need to write your php code like this

You can use this script If u can want particular cookie

<script>
function getCookie(cname) {
    var name = cname + "=";
    var ca = document.cookie.split(';');
    for(var i=0; i<ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') c = c.substring(1);
        if (c.indexOf(name) == 0) return c.substring(name.length,c.length);
    }
    return "";
}

console.log(getCookie('test'));
<script>

Question 5

Make sure you have a domain that is known by both server and client. echo $_SERVER['HTTP_HOST'] should tell you the exact same domain that your browser has. If not, cookie will not be accepted by the browser.

Make sure your server and client time is perfectly correct. Browser will reject a cookie with a wrong datetime.

Do not write any other code and just do:

<?php
$cookie_name = "user";
$cookie_value = "John Doe";
setcookie($cookie_name, $cookie_value, time() + (86400 * 30), "/"); // 86400 = 1 day 
// expiration
echo date("H:i:s d.m.Y")."<br>";
echo $_SERVER['HTTP_HOST']."<br>";
var_dump($_COOKIE);
?>

and refresh the page twice.

Also check out manual at: https://www.php.net/manual/en/features.cookies.php

Question 6

This should be possible with IIS using the host headers field in the bindings settings. You can add as many different host headers as you want for your application. And as long as that domain somehow goes to that host on that particular port (http or https or custom), then that application will be used.

Set cookie on multiple domains with PHP or JavaScript

Answers

setcookie.php

javascript,php,cookies,setcookie