[MM-40485] Enable receiving binary websocket messages (#19128)

* Enable receiving binary websocket messages

* Improve error message

* Prefer anonymous declaration

* Simplify

* Improve test

* Use MessagePack to clone WebSocketRequest struct

* Use short form

* Fix test

api4/websocket_test.go

@@ -234,6 +234,47 @@ func TestWebSocketReconnectRace(t *testing.T) {
 	wg.Wait()
 }
 
+func TestWebSocketSendBinary(t *testing.T) {
+	th := Setup(t).InitBasic()
+	defer th.TearDown()
+
+	client := th.CreateClient()
+	th.LoginBasicWithClient(client)
+	WebSocketClient, err := th.CreateWebSocketClientWithClient(client)
+	require.NoError(t, err)
+	defer WebSocketClient.Close()
+	WebSocketClient.Listen()
+	resp := <-WebSocketClient.ResponseChannel
+	require.Equal(t, resp.Status, model.StatusOk)
+
+	client2 := th.CreateClient()
+	th.LoginBasic2WithClient(client2)
+	WebSocketClient2, err := th.CreateWebSocketClientWithClient(client2)
+	require.NoError(t, err)
+	defer WebSocketClient2.Close()
+
+	time.Sleep(1000 * time.Millisecond)
+
+	WebSocketClient.SendBinaryMessage("get_statuses", nil)
+	resp = <-WebSocketClient.ResponseChannel
+	require.Nil(t, resp.Error, resp.Error)
+	require.Equal(t, resp.SeqReply, WebSocketClient.Sequence-1)
+
+	status, ok := resp.Data[th.BasicUser.Id]
+	require.True(t, ok)
+	require.Equal(t, model.StatusOnline, status)
+	status, ok = resp.Data[th.BasicUser2.Id]
+	require.True(t, ok)
+	require.Equal(t, model.StatusOnline, status)
+
+	WebSocketClient.SendBinaryMessage("get_statuses_by_ids", map[string]interface{}{
+		"user_ids": []string{th.BasicUser2.Id},
+	})
+	status, ok = resp.Data[th.BasicUser2.Id]
+	require.True(t, ok)
+	require.Equal(t, model.StatusOnline, status)
+}
+
 func TestWebSocketStatuses(t *testing.T) {
 	th := Setup(t).InitBasic()
 	defer th.TearDown()