Access request header in plugin configuration

Hi all,

we use the Http input plugin to process events via http request in Logstash. The Logstash version is 7.16.2.

With the http request we get a special http header, e.g.

x-test-header: test-value

We now want to reuse the value from this header in a reponse header. How can we access the value of the header?

input {
    http {
        response_headers => {
        "x-test-header" => "test-value"

Is it possible to access the value in the plugin configuration?

Best regards,