setting cross-subdomain cookie with javascript

Question

How should I add domain support to these functions? I want to achieve that .example.com is declared as domain, so that the cookies can be read across all subdomains of the example.com. In its current form since domain is not set, it can only be read from www.example.com

Jaret

Answer 1

Here is a link on how to share cookies amongst a domain:

https://www.thoughtco.com/javascript-by-example-2037272

It involves setting the domain attribute of the cookie string like:

document.cookie = "myValue=5;path=/;domain=example.com";

This cookie should now be accessible to all sub domains of example.com like login.example.com

Cataphoresis

the syntax of ppk's function seems to be different because it gets its name and expiry from its lines above: document.cookie = name+"="+value+expires+"; path=/"; what about these double quotes? – Jaret

@newnomad: JavaScript uses quotes around string literals like most programming languages. – Katharinekatharsis

this cant be added to cookies if I dont escape() it. but if escape - value set with path and domain – Jaguar

I was having a similar problem, and although I was putting in a leading dot before the domain name (in order for it to be available to another subdomain), it wasn't showing until I added the path=/ portion. – Quartan

The link doesn't explain anything. – Imperception

Answer 2

In my case we needed to set a cookie that would work across our .com subdomains:

function setCrossSubdomainCookie(name, value, days) {
  const assign = name + "=" + escape(value) + ";";
  const d = new Date();
  d.setTime(d.getTime() + (days*24*60*60*1000));
  const expires = "expires="+ d.toUTCString() + ";";
  const path = "path=/;";
  const domain = "domain=" + (document.domain.match(/[^\.]*\.[^.]*$/)[0]) + ";";
  document.cookie = assign + expires + path + domain;
}

This might not work for .co.uk etc but the principle can be used

Evasive

How would I modify this to work with .co.uk as well? Assuming it needs some regex changing – Wafture