Origin header not the same as the URL

Question

We made a website for another company, we have the server, they provide the hostname. There are 3 ways to access the website so far :

• IP Address (Ours) : You access directly the website hosted in our server
• A redirection hostname 1 (Theirs) : Something like www.link1.com that redirects to the IP address
• Woops ! We have to change the website's name, so we're gonna provide you with a second hostname that redirects to the first hostname and not the IP address, because we're stupid

The website calls web services in our server (Same IP address). From the first hostname, calls to web services work with no problem because the URL is pointing on the IP address. In the second hostname I get a Cross Domain (CORS) error, because it's pointing to the second hostname and not the IP address.

Probable solution : replace IP address part on web service by the current URL

Answer 1

Ended up replacing the IP address in web services URLs by location.origin. Now it's working !