Unexpected Behavior: httpHeaders Callback Invoked for Every Request Instead of Only During Initial CONNECT in Netty HTTP Client with Proxy

[matthew-js-porter]

When configuring a Netty HTTP client to use a proxy, I would have expected the headers callback specified in the ProxyProvider to be called only during the initial CONNECT request to the proxy server and that after the tunnel was created there would be no need to call the headers callback. Is my understanding on the proxy correct or am I completely off base here?

Expected Behavior

The httpHeaders method to be called only when creating the tunnel to the Proxy.

Actual Behavior

The httpHeaders method is ran for every request the httpClient makes.

Steps to Reproduce

Configure HTTP Client with a Proxy like this. When making requests observe that the httpHeaders method is ran for each request.

final var httpClient = HttpClient.create().proxy(proxy -> proxy.type(ProxyProvider.Proxy.HTTP).host(proxyUrl).port(proxyPort).httpHeaders(headers -> {
            System.out.println("in headers");
           //headers.add("Proxy-Authorization", "Negotiate " + getKerberosToken());
        }).build());

• Reactor version(s) used: Reactor Netty 1.1.22