Proxy behing another Proxy in Relay

proxychain.go

// Each hop to the test server takes 1 second
delay := time.Duration(1) * time.Second
ts := httptest.NewServer(http.HandlerFunc(handler))
p3 := relay.NewProxy(delay, ts)
p2 := relay.NewProxy(delay, p3)
p1 := relay.NewProxy(delay, p2)
start := time.Now()
resp, _ := client.Get(p1.URL)
elapsed := time.Since(start)
So(elapsed, ShouldAlmostEqual, time.Duration(6) * time.Second)