fetch vs. undici.fetch

[tiptronic]

Using node 20.0.0:

I just read to the available documentation on undici, but can't figure out what's the difference in just using fetch vs.
import { fetch } from 'undici' (as suggested in undici's ReadMe).

Can someone shed some light on this?

I am basically looking into 2 things (localhost only, atm):

• a fast way to ping a device (currently I'm using new net.Socket() with callback, which works, but with some latency)
• collecting small amounts of information (< 500bytes) from a bunch of devices = ~10 (using fetch)

Everything above work using net.Socket and fetch, but I am wondering what's the best way to fetch small amounts of information in a short timeframe < 0.1sec

Any pointer to examples appreciated as well!

Btw.: I can't use Websockets here, because those devices don't support it

[mcollina]

The only difference is on the fact that you need to install one from npm and the other is already bundled in core, possibly with a different version.

[JasonKleban]

How can we figure out which version of Undici has been incorporated in to a Node version, please?

[KhafraDev]

you can use process.versions.undici

[tiptronic]

Hi @mcollina
thanks for that info.
I think it would be great to mention this info somewhere in the docs.

So, I only need the npm version, if I want to make use of Pooling or other features not available in fetch, correct?

And while I'm here: will the WebSocket find their way into core as well? If yes - is there a time-frame? (I played with undici.WebSocket, but they didn't work reliably (yet)... I know it's experimental...

[mcollina]

So, I only need the npm version, if I want to make use of Pooling or other features not available in fetch, correct?

Yes

And while I'm here: will the WebSocket find their way into core as well? If yes - is there a time-frame?

Possibly. There is no time frame atm.

played with undici.WebSocket, but they didn't work reliably (yet)...

Please open issues.

[tiptronic]

thx @mcollina
I'll create issues as soon as I have more time to play with WebSockets

[cristobal]

Ok so there is no bundled undici with nodejs at all?
Does not seem like it:

Some other questions i'm wondering about:

1. So if i want to set specific agent i would have to actually use the fetch from undici instead? Or can i set an agent dispatcher to native fetch?
2. As far as i understand an undici dispatcher agent is not the same as an http(s) agent?

[mcollina]

So if i want to set specific agent i would have to actually use the fetch from undici instead?

No, you can use native fetch.

Or can i set an agent dispatcher to native fetch?

Calling undici.setGlobalDispatcher() affects all undici and fetch instances.

As far as i understand an undici dispatcher agent is not the same as an http(s) agent?

No, it's a reimplementation.

[Matteobikk90]

hello everyone,
I am using node v20.11.0, I guess the latest stable version but I cannot get rid of: fetch is not defined.
Why?

[surfmuggle]

Since Nodes.js v20.00 fetch should be available; it returns a Response object

C:\>node
         Welcome to Node.js v20.11.1.      
         Type ".help" for more information.
fetch('https://example.com').then(rsp => {console.log(rsp.headers)}) // get request to url
// prints out the headers
HeadersList {
  cookies: null,
  [Symbol(headers map)]: Map(13) {
    'content-encoding' => { name: 'Content-Encoding', value: 'gzip' },
    'content-type' => { name: 'Content-Type', value: 'text/html; charset=UTF-8' },
     ...
    'content-length' => { name: 'Content-Length', value: '648' }
  },
  [Symbol(headers map sorted)]: null
}

[liudonghua123]

$ node
Welcome to Node.js v20.5.1.
Type ".help" for more information.
> process.versions.undici
'5.22.1'
>