To enable CORS in Joomla!, you need to add the standard CORS header(s). There are a few ways to add the header(s), which are covered in the following sections.
Since Joomla! version 11.4, the core method to set headers is setHeader in the base class JapplicationWeb, which can be used to set the Access-Control-Allow-Origin header and can be used to set other headers.
The following example allows access from all domains with the wildcard:
setHeader('Access-Control-Allow-Origin', '*', true) : \JApplicationWebYou may find discussions regarding the use of JResponse::setHeader for CORS in Joomla!; however, it has been deprecated since Joomla! Version 11.4. Use setHeader in the base class JApplicationWeb instead.