node reciving an unhandled error event need some insite? - node.js

Question

I've searched Hi and Low through web sites and docs, and I've yet to figure out why Im getting this error. Yes I'm new to node. I thought id ask here as a last resort.
the error I'm receiving is:
events.js:292
throw er; // Unhandled 'error' event
^
Error [ERR_STREAM_WRITE_AFTER_END]: write after end
at writeAfterEnd (_http_outgoing.js:668:15)
at ServerResponse.end (_http_outgoing.js:789:7)
at Server.<anonymous> (/mnt/sdc/opt/codeWork/ReactBuilds/be_full-stack/app.js:10:9)
at Server.emit (events.js:315:20)
at parserOnIncoming (_http_server.js:874:12)
at HTTPParser.parserOnHeadersComplete (_http_common.js:126:17)
Emitted 'error' event on ServerResponse instance at:
at writeAfterEndNT (_http_outgoing.js:727:7)
at processTicksAndRejections (internal/process/task_queues.js:81:21) {
code: 'ERR_STREAM_WRITE_AFTER_END'
}
Here's my code I'm running node v14.16.0
const http = require('http')
const server = http.createServer((req, res)=>{
if(req.url === '/') {
res.end('Welcome to our home page')
}
if(req.url === '/about') {
res.end('Here is our short history')
}
res.end(`
<h1>Ooops</h1>
<p>This is not the page you are looking for</p>
backHome
`)
})
server.listen(5000)
any incites are very welcome
Thanks

Answer 1

You should introduce early returns in your code so that you don't call res.end multiple times when one of the conditions evaluates to true with your request handler still handling 404:
const server = http.createServer((req, res) => {
if (req.url === "/") {
return res.end("Welcome to our home page");
}
if (req.url === "/about") {
return res.end("Here is our short history");
}
res.end(`
<h1>Ooops</h1>
<p>This is not the page you are looking for</p>
backHome
`);
});