how to cache in node js?

Question

I am new to nodejs. I have one API which returns file in response. Currently when I get the request, I read the file every time and send it. Can we do caching in memory to speed up?

I checked this package. can we use this package to speed up. https://www.npmjs.com/package/memoizee

 server.get('/user', (req, res) => {
    res.sendFile(path.join(distFolder,'user','index.html'))
  });

Current what I am doing

Right now I am running node server.when /user request come on I am sending html file .while is working fine.

can we optimise this ? can we cache this file ?

you're sending a static file - what would you cache on the server? — Jaromanda X, Aug 25 '22 at 03:53
You should look into the [HTTP caching](https://developer.mozilla.org/en-US/docs/Web/HTTP/Caching) if you just send to a static file back. — Pylon, Aug 25 '22 at 03:55
@JaromandaX can we set some header so that it file come from cache second request or other than first request — , Aug 25 '22 at 03:59
Oh, so you want to cache the file in memory so you don't have to read the file every time you send it - if on the other hand you're talking about client (browser) caching so the client doesn't need the response every time ... there is [this](http://expressjs.com/en/resources/middleware/serve-static.html) (I'm assuming you're using expressjs of course) — Jaromanda X, Aug 25 '22 at 04:02
@JaromandaX..I am taking about this <>> client will always send request but I need to send from cache — , Aug 25 '22 at 04:09
can you please help me how we memoizing in node js . first request with from sendfile , rest req will be from memoizing — , Aug 25 '22 at 04:21

Jaromanda X · Accepted Answer · 2022-08-25T05:02:06.040

0

A simple approach

import { readFileSync } from "node:fs";

const cache = {};
const simpleCache = path => {
    if (!cache[path]) {
        cache[path] = readFileSync(path).toString();
    }
    return cache[path];
};
server.get('/user', (req, res) => {
    res.send(simpleCache(path.join(distFolder,'user','index.html')));
});

edited Aug 25 '22 at 05:02

answered Aug 25 '22 at 04:29

Jaromanda X

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sorry I understand the code .. but using above code it downloading file ..it is not showing anything on browser... but when I was using this code ` res.sendFile(path.join(distFolder,'user','index.html')) `. it is showing HTML content – Aug 25 '22 at 04:43
I must've done something wrong then - probably the format of the data `readFileSync` gets is wrong ... perhaps you need `fs.readFileSync(path).toString()` – Jaromanda X Aug 25 '22 at 04:48
you did remember to import/require `fs`? right? – Jaromanda X Aug 25 '22 at 05:00
sorry still it downloading..not working I will try another solution – Aug 25 '22 at 05:09
@naveen - that's odd, works for me like a bought one ... and ... you get no errors at all? – Jaromanda X Aug 25 '22 at 05:20
I am not getting error but if I am hitting `localhost:3000/user` --> it download the file with name `user`. content is there in file – Aug 25 '22 at 05:25
so, it's getting a file, just not the right one? – Jaromanda X Aug 25 '22 at 05:37

how to cache in node js?

1 Answers1