Why the nodejs net socket does not send the data in the first connection?

Question

Hello,

this is my code in lambda which runs based on SQS messages arrival.

var net = require('net');
let client = new net.Socket();
            console.log(" ------------------- Attempt to connect...  --------------------");
            client.connect(port, 'ip', () => {
                console.log(" ------------------- Connected --------------------");
                client.write(jsonres.raw_message); //This will send the byte buffer over TCP
                console.log(" ------------------- Message Sent! --------------------");
                client.end();
                console.log(" ------------------- Disconnected --------------------");
            });

If I run this code from my PC it works but from AWS lambda I don't reach "connected" state. In the pcap I see the TCP init with 3 messages, SYN + SYN/ACK + ACK but no PSH/data. Why?
If I send another message in short time I will get the first message in the serveer... It's like its on holding in AWS and just sent in the next connect...
delay/Promise does not work. 
any idea?

Answer

solved by using function with callback.
Tks to this page:
https://docs.aws.amazon.com/lambda/latest/dg/best-practices.html

Why the nodejs net socket does not send the data in the first connection?

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