istio send custom dynamic header to application by either using uuid or refer value from another already exiting header

Question

Is there way in istio to set a custom request header (x-custom-header) with value as dynamic value (uuid) or setting value of the custom header from an already existing header?

I am using gateway + virtualservice + envoy(sidecar)

Example configuration options in nginx = proxy_set_header x-custom-header $connection:$connection_requests;

I tried below snippet in my virtual service and got literal value "{{ uuid }}" forwarded to my application.

` http:

• headers: request: set: x-custom-header: '{{ uuid() }}'

  match:

  • uri: prefix: /`

Answer 1

I was able to solve this by using following snippet in virtual service

   http:
  - headers:
      request:
        set:
          x-custom-header: '%REQ(x-request-id)%'