Socket.io emit requested data to each client conti

Here is the code :

Client

var server = "localhost";
var socket = io('http://' + serve + ':4005');
socket.on('connect',function(){ 
socket.emit('send', {type:"<?php echo $datatype?>"}); //{type:"3,2"}
  });

Here is the code for my node js server:

Server

io.on('connection', function(client) {

    console.log('Client connected...');

    client.on('join', function(data) {
        console.log(data);
    });
    client.on('send',function(data){
        var datafinal = [];

        setInterval(function () {
        var usertype = data.type;
        var types = usertype.split(',');
            for (var i = 0; i < types.length; i++){
                datafinal.push(apifinaldata.filter((inbound) => inbound.usertype == types[i] && inbound.active == 1 ));
                }
                var final = datafinal.reduce(function(a, b) {
                    return a.concat(b);
                }, []);

                datafinal = [];

            io.emit('finaldata', final); io.emit('callwaiting', callsdatafinal);
        }, 1000);
    })


});

server.listen(4005);

When I start the server, it receives a request from client A with the type of data it want's (eg {type : "3,2" }. So the server emits only that specific data to client. But when a different client say B asks the server to send data of {type : "1"}, in this case the server emits the correct data to client A and B each but the clients don't receive the data continously. The server keeps emitting continously but sometimes it sometimes emits to A and sometimes to B. I want the server to continously emit the requested data to each of the connected clients.

Also if I change io.emit('finaldata', final); io.emit('callwaiting', callsdatafinal); to client.emit('finaldata', final); client.emit('callwaiting', callsdatafinal); it doesn't emit any data to any client.

So I want a solution such that the server emits continuously to each client only the specific data requested by each client

How can I do this?

For this you have to keep track of both the clients A and B then send data to specific client only, Below is sample code.

var clientA;
var clientB;
io.on('connection', function(client) {
    console.log('Client connected...');

    client.on('join', function(data) {
        if (something){
          clientA = client;
        }
        else {
          clientB = client;
        }
        console.log(data);
    });
    client.on('send',function(data){
        var datafinal = [];

        setInterval(function () {
        var usertype = data.type;
        var types = usertype.split(',');
            for (var i = 0; i < types.length; i++){
                datafinal.push(apifinaldata.filter((inbound) => inbound.usertype == types[i] && inbound.active == 1 ));
                }
                var final = datafinal.reduce(function(a, b) {
                    return a.concat(b);
                }, []);

                datafinal = [];

            if(someCondition){
              clientA.emit('finaldata', final);
              clientA.emit('callwaiting', callsdatafinal);
            }
            else {
              clientB.emit('finaldata', final);
              clientB.emit('callwaiting', callsdatafinal);
            }
        }, 1000);
    })
});

Here clientA and clientB are two clients connected, You can send data to any client based on conditions or program logic.