hx-headers ~ htmx

The hx-headers attribute allows you to add to the headers that will be submitted with an AJAX request.

By default, the value of this attribute is a list of name-expression values in JSON (JavaScript Object Notation) format.

Syntax


<div hx-get="/data" hx-headers='{"myHeader": "My Value"}'>Get Data</div>

If you wish for hx-headers to evaluate the values given, you can prefix the values with javascript: or js:.


  <div hx-get="/example" hx-headers='{"myHeader": "My Value"}'>Get Some HTML, Including A Custom Header in the Request</div>

  <div hx-get="/example" hx-headers='js:{myVal: calculateValue()}'>Get Some HTML, Including a Dynamic Custom Header from Javascript in the Request</div>

Security Considerations

By default, the value of hx-headers must be valid JSON. It is not dynamically computed. If you use the javascript: prefix, be aware that you are introducing security considerations, especially when dealing with user input such as query strings or user-generated content, which could introduce a Cross-Site Scripting (XSS) vulnerability.
Whilst far from being a foolproof solution to Cross-Site Request Forgery, the hx-headers attribute can support backend services to provide CSRF prevention. For more information see the CSRF Prevention section.

Notes

A child declaration of a header overrides a parent declaration.