I have async job inside looping from server side:
const contacts = [];
for(contact of contacts){
(async () => {
await MailService.sendMessage(contact, 'message body')
})()
}
I want to break that looping using client side, what i do is:
1 . from server side, before sendMessage, check if Broadcast status is process or stopped, if stopped, than break looping.
2 . from client side, if i want to stop the Broadcast(stop looping), i need to update Broadcast value from process to stopped.
So, my code should be:
server side:
const contacts = [];
for(contact of contacts){
(async () => {
const currentBroadcast = await Broadcast.findById('id')
if(currentBroadcast.status === 'stopped') break;
await MailService.sendMessage(contact, 'message body')
})()
}
client side:
document.getElementById('stop').addEventListener('click', () => {
fetch('url/broadcast/stop/:id')
})
it works. But wouldn't that make the server heavy? Because in every loop I have to check into the database.
is there any other way i can do to stop the looping? without having to check into the database.
You don't need a database for that - you just need to update a value that can be seen in the server's code. You could have a plain Express route that adds client session IDs to a collection, which gets updated when the route is called. Then, just have your loop check whether that client's sent such a request.
With sessions, you could have something like, with a route:
const stoppedBroadcastSessionIds = new Set();
app.post('/stopbroadcast', function (req, res) {
stoppedBroadcastSessionIds.add(req.session.id);
})
and then do
for(const contact of contacts){
if (stoppedBroadcastSessionIds.has(req.session.id)) break;
await MailService.sendMessage(contact, 'message body')
}