Logger logs unsent request headers even though Default in Client has restricted headers

[facewise]

Since the default class Default in Client uses sun.net.www.protocol.http.HttpURLConnection, which has the set of restricted headers, even if I add a header using RequestTemplate#header(String, String), the actual HTTP request does not contain the header.

However feign.Logger logs not the actual request but the Request made by SynchronousMethodHandler#executeAndDecode(), which contains the restricted header I have added.

This inconsistency made me hard to discover the problem because there's no such documentation tells the logged request may not be the same as the actual HTTP request.

I hope to add some documentation that tells RequestTemplate you applied may not be the actual request or, if possible, make Logger logs the actual HTTP request.