httptrace.go

import "net/http/httptrace"

func (cl *httpClient) makeTrace(kvs []*kvpb.KV) *httptrace.ClientTrace {
	start := cl.timeNow()

	var (
		startDial    = start
		startDNS     = start
		startConnect = start
		startTLS     = start
	)
	return &httptrace.ClientTrace{
		GetConn: func(hostPort string) {
			startDial = cl.timeNow()
		},
		GotConn: func(httptrace.GotConnInfo) {
			cl.measureDuration("http_call_get_conn_duration", kvs, startDial, cl.timeNow(), "tcp", "dial")
		},
		DNSStart: func(httptrace.DNSStartInfo) {
			startDNS = cl.timeNow()
		},
		DNSDone: func(dnsif httptrace.DNSDoneInfo) {
			kvs := kvs
			if dnsif.Err != nil {
				kvs = append(kvs, &kvpb.KV{Key: "err", Value: dnsif.Err.Error()})
			}
			cl.measureDuration("http_call_resolve_dns_duration", kvs, startDNS, cl.timeNow(), "dns", "resolve")
		},
		ConnectStart: func(network, addr string) {
			startConnect = cl.timeNow()
		},
		ConnectDone: func(network, addr string, err error) {
			kvs := append(kvs,
				&kvpb.KV{Key: "network", Value: network},
				&kvpb.KV{Key: "addr", Value: addr},
			)
			if err != nil {
				kvs = append(kvs, &kvpb.KV{Key: "err", Value: err.Error()})
			}
			cl.measureDuration("http_call_connect_duration", kvs, startConnect, cl.timeNow(), "tcp", "connect")
		},
		TLSHandshakeStart: func() {
			startTLS = cl.timeNow()
		},
		TLSHandshakeDone: func(cs tls.ConnectionState, err error) {
			kvs := append(kvs,
				&kvpb.KV{Key: "nego_proto", Value: cs.NegotiatedProtocol},
				&kvpb.KV{Key: "server_name", Value: cs.ServerName},
			)
			if err != nil {
				kvs = append(kvs, &kvpb.KV{Key: "err", Value: err.Error()})
			}
			cl.measureDuration("http_call_tls_handshake_duration", kvs, startTLS, cl.timeNow(), "tcp", "tls_handshake")
		},
		GotFirstResponseByte: func() {
			cl.measureDuration("http_response_first_byte_duration", kvs, start, cl.timeNow(), "http", "first_bytes")
		},
		WroteHeaders: func() {
			cl.measureDuration("http_request_wrote_header_duration", kvs, start, cl.timeNow(), "http", "wrote_header")
		},
		WroteRequest: func(wrif httptrace.WroteRequestInfo) {
			kvs := kvs
			if wrif.Err != nil {
				kvs = append(kvs, &kvpb.KV{Key: "err", Value: wrif.Err.Error()})
			}
			cl.measureDuration("http_request_wrote_request_duration", kvs, start, cl.timeNow(), "http", "wrote_request")
		},
	}
}