nodejs set timeout on data response - node.js

Question

I am trying to set a timeout in between readstream.write but I keep getting Error: write after end. How can I set a timeout in between res.write. Thank you. Here is my code.
app.get('/video', function (req, res) {
var readStream = fs.createReadStream('video.mjpeg');
res.writeHead(200, {'Content-Type': 'multipart/x-mixed- replace;boundary=ThisString'});
readStream.on("data", (chunk) => {
res.write(chunk, 'binary');
setTimeout(function () {
res.write('ThisString');
}, 200);
console.log("Writing to client");
});
readStream.on("end", () => {
readStream.destroy();
res.end();
console.log("End of data");
});
});
I am trying to display the video on the client side, the problem is that the mjpeg gets read quickly thus cannot create the video. Any help will be appreciated.

Answer 1

I wrote quickly some line of code of what I understand you need.
StackOverflow is not my favorite IDE so don't be too hard on it ^^
I don't really know the readStream but data event is called many time write ?
The queue is waiting the precedent chunk and its timeout are correctly finished.
Is it what you need ?
var kue = require('kue'),
jobs = kue.createQueue();
app.get('/video', function (req, res) {
var readStream = fs.createReadStream('video.mjpeg');
res.writeHead(200, {'Content-Type': 'multipart/x-mixed- replace;boundary=ThisString'});
jobs.process('write chunck', function (job, done) {
setTimeout(function() {
res.write(job.chunck, 'binary');
done && done();
}, 200);
});
jobs.process('write end', function(job, done) {
readStream.destroy();
res.end();
console.log("End of data");
done & done();
});
readStream.on("data", (chunk) => {
jobs.create('write chunck', {
chunk: chunk
});
});
readStream.on("end", () => {
jobs.create('write end', {});
});
});