Whats the mean of x value on stream Kline? binance-spot-api-docs/web-socket-streams.md at master · binance/binance-spot-api-docs · GitHub
i.e. “Is this kline closed?”
If its opened, its the current one (since it return the current one). If its closed, won’t be the current candle (since the system return only the current one, not the prev/closed).
Can you help me to get this concept?
Thanks
As long as I understand what you are asking:
When x is false the min , max , open and close inside the stream are not valid since the candle is still open.
(If we should be completely accurate-> the open is right but the close, min and max are not)
When x is set to true , all candle parameters are right.
In other words, if x is not true , ignore the websocket message.
This make no sense to me 
Isn’t stream returning only the last/current opened candle? (i.e. it returns only 1 object).
It will never be x = true, else this means that another candle has been opened, but at this point system should return it so, not a closed one 
if you are listening to the 1h time chart, and the wall clock is 15:40,
the values in this stream will be right for the period 15:00-15:40 and x will be false
at exactly 16:00 there will be one message with x equal to true
and then again …
at 16:01 the values in the stream will be right for the period 16:00-16:01.
at 16:15 the values in the stream will be right for the period 16:00-16:15. and so on…
yes you are right if you want the candle sticks, there is no meaning in every other value of the stream except when x is true.
The stream itself–>between the candle closings the stream itself is not the aggregate trades. It is sending you a message every 5-10 aggregate trades. So it is rather pointless. Can not be used for anything.
the field x when it is true indicates that the data you are receiving is the last of the current candle, the next time you receive data it will be from the new candle