add test

receiver/statsdreceiver/internal/transport/client/client.go

@@ -51,6 +51,15 @@ func (s *StatsD) connect() error {
 		if err != nil {
 			return err
 		}
+	case "unixgram":
+		unixAddr, err := net.ResolveUnixAddr(s.transport, s.address)
+		if err != nil {
+			return err
+		}
+		s.conn, err = net.DialUnix(s.transport, nil, unixAddr)
+		if err != nil {
+			return err
+		}
 	default:
 		return fmt.Errorf("unknown/unsupported transport: %s", s.transport)
 	}

receiver/statsdreceiver/internal/transport/packet_server.go

@@ -28,6 +28,13 @@ func (u *packetServer) ListenAndServe(
 	buf := make([]byte, 65527) // max size for udp packet body (assuming ipv6)
 	for {
 		n, addr, err := u.packetConn.ReadFrom(buf)
+		if addr == nil && u.transport == UDS {
+			addr = &udsAddr{
+				network: u.transport.String(),
+				address: u.packetConn.LocalAddr().String(),
+			}
+		}
+
 		if n > 0 {
 			u.handlePacket(n, buf, addr, transferChan)
 		}
@@ -62,3 +69,16 @@ func (u *packetServer) handlePacket(
 		}
 	}
 }
+
+type udsAddr struct {
+	network string
+	address string
+}
+
+func (u *udsAddr) Network() string {
+	return u.network
+}
+
+func (u *udsAddr) String() string {
+	return u.address
+}

receiver/statsdreceiver/receiver_test.go

@@ -106,6 +106,24 @@ func Test_statsdreceiver_EndToEnd(t *testing.T) {
 				return c
 			},
 		},
+		{
+			name: "UDS server with 4s interval",
+			addr: "/tmp/statsd_test.sock",
+			configFn: func() *Config {
+				return &Config{
+					NetAddr: confignet.AddrConfig{
+						Endpoint:  "/tmp/statsd_test.sock",
+						Transport: confignet.TransportTypeUnixgram,
+					},
+					AggregationInterval: 4 * time.Second,
+				}
+			},
+			clientFn: func(t *testing.T, addr string) *client.StatsD {
+				c, err := client.NewStatsD("unixgram", addr)
+				require.NoError(t, err)
+				return c
+			},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {