Function deadUpstreamAddr

modules/caddyhttp/reverseproxy/retries_test.go:66–75

deadUpstreamAddr returns a TCP address that is guaranteed to refuse connections: we bind a listener, note its address, close it immediately, and return the address. Any dial to that address will get ECONNREFUSED.

(t *testing.T)

// connections: we bind a listener, note its address, close it immediately,
// and return the address. Any dial to that address will get ECONNREFUSED.
func deadUpstreamAddr(t *testing.T) string {
	t.Helper()
	ln, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("failed to create dead upstream listener: %v", err)
	}
	addr := ln.Addr().String()
	ln.Close()
	return addr
}

// testTransport wraps http.Transport to:
//  1. Set the URL scheme to "http" when it is empty (matching what