Method ApplyToRequest

modules/caddyhttp/headers/headers.go:344–375

ApplyToRequest applies ops to r, specially handling the Host header which the standard library does not include with the header map with all the others. This method mutates r.Host.

(r *http.Request)

// header which the standard library does not include with the
// header map with all the others. This method mutates r.Host.
func (ops HeaderOps) ApplyToRequest(r *http.Request) {
	repl := r.Context().Value(caddy.ReplacerCtxKey).(*caddy.Replacer)

	// capture the current Host header so we can
	// reset to it when we're done
	origHost, hadHost := r.Header["Host"]

	// append r.Host; this way, we know that our value
	// was last in the list, and if an Add operation
	// appended something else after it, that's probably
	// fine because it's weird to have multiple Host
	// headers anyway and presumably the one they added
	// is the one they wanted
	r.Header["Host"] = append(r.Header["Host"], r.Host)

	// apply header operations
	ops.ApplyTo(r.Header, repl)

	// retrieve the last Host value (likely the one we appended)
	if len(r.Header["Host"]) > 0 {
		r.Host = r.Header["Host"][len(r.Header["Host"])-1]
	} else {
		r.Host = ""
	}

	// reset the Host header slice
	if hadHost {
		r.Header["Host"] = origHost
	} else {
		delete(r.Header, "Host")
	}
}

// responseWriterWrapper defers response header
// operations until WriteHeader is called.