Node.js and socket.io - Accumulate datas before pushing database - mysql

Question

I'm newby at Node.js and Socket.io. I wonder if i accumulate the data which users entered from UI, then, these datas collecting at the server and pushing database at intervals. For example, different users entering messages from their accounts continuously, and these datas collecting at the server. every 1 minutes, collected datas push into database, and the data pool will drain off. Is it possible with node.js and socket.io?

Answer 1

You can achieve such result pretty easily in NodeJS.
Just accumulate your messages in an hashmap (let say a key per user) and trigger a timeout on every minute to flush your hashmap into your database.
var messages = {};
io.sockets.on('connection', function (socket) {
socket.on('message', function (data) {
// data.id is user id, data.content the message
if (!(data.id in messages)) {
messages[data.id] = []
}
messages[data.id].push(data.content);
});
});
var flush = function() {
for (userId in messages) {
// ... write in database
// effectively flush messages
messages[userId] = [];
}
// Don't forget to set agin the next flush
setTimeout(flush, 1000);
}
setTimeout(flush, 1000);
Its a naive solution which will be very easy to setup and test.
Don't use setInterval, which is verry greedy on CPU time.
As this example is single-threaded, your server will be unavailable during the (short) time it will write on the database.
If you need a highly available server, consider use another process for storing and flushing messages, and send it your messages instead of storing them into the main (communication) process.