Using child_process to run long running task

long.js

//child

const longTask = () => {

let sum = 0;

for (let i = 0; i < 1e9; i++) {

sum += i;

};

return sum;

};

process.on('message', (msg) => {

console.log("child",msg);

const sum = longTask();

process.send(sum);

});

We have long running task longTask as above.To call this long running task we

create end point as below

Main.js

//parent

const http = require('http');

const { fork } = require('child_process');

const server = http.createServer();

server.on('request', (req, res) => {

if (req.url === '/get') {

const compute = fork('long.js');

compute.send('start');

compute.on('message', sum => {

res.end(`Sum is ${sum}`);

});

} else {

res.end('Ok')

}

});

server.listen(3000);

when localhost:3000/get called long.js is forked and now when message from

child process come response is send.