Add HTTP Signature and Digest headers with Spring Cloud Gateway

Question

I would like to add some http headers to requests running through a Spring Cloud Gateway. The issue is that there seems to be methods for adding headers, and methods for doing something with the body, but no method that allows me to adjust the headers while looking at the body.

The reason I need to look at the body while making headers is to create the digest for the http signature.

How I can add headers and body while being unable to look at the body while updating the headers:

.filters(f -> {
  return f
    .addResponseHeader("foo", "bar")
    .modifyRequestBody(String.class, String.class,
      (exchange, s) -> {
        ...
    })

Is there a way to use addRequestHeader() while also seeing the body?

Answer 1

You're going to need to write your own routefilter for that.

See https://www.baeldung.com/spring-cloud-custom-gateway-filters for example