Method Conn4

tests/t.go:426–458

Conn4 connects to the server listener at the specified named port using one of 127.0.0.0/8 addresses as a source.

(sourceIP, portName string)

// Conn4 connects to the server listener at the specified named port using one
// of 127.0.0.0/8 addresses as a source.
func (t *T) Conn4(sourceIP, portName string) Conn {
	port := t.ports[portName]
	if port == 0 {
		panic("tests: connection for the unused port name is requested")
	}

	localIP := net.ParseIP(sourceIP)
	if localIP == nil {
		panic("tests: invalid localIP argument")
	}
	if localIP.To4() == nil {
		panic("tests: only IPv4 addresses are allowed")
	}

	conn, err := net.DialTCP("tcp4", &net.TCPAddr{
		IP:   localIP,
		Port: 0,
	}, &net.TCPAddr{
		IP:   net.IPv4(127, 0, 0, 1),
		Port: int(port),
	})
	if err != nil {
		t.Fatal("Could not connect, is server listening?", err)
	}

	return Conn{
		T:            t,
		WriteTimeout: 1 * time.Second,
		ReadTimeout:  15 * time.Second,
		Conn:         conn,
		Scanner:      bufio.NewScanner(conn),
	}
}

var (
	DefaultSourceIP    = net.IPv4(127, 109, 97, 100)