http-client doesn't receive any data since Node is updated

[ZivojnovicZarko]

Expected behaviour
dd-trace should send data to datadog http-client service

Actual behaviour
http-client service is missing data

Environment

• Node.js version: 18.12.1
• Tracer version: 3.11.0
• Relevant library versions: Next.js 12.3.1

After updating Node to v.18 on our Next.js project datadog stopped receiving http-client data. On other Node.js project not using Next everything work fine, so our assumption is that something is wrong with combination Next.js / Node 18.
When downgrade Node to version 16.17.0 http-client service is back.

Any idea what should be the issue?

[tlhunter]

Can you provide a minimal reproduction? Something that I can easily run locally that exhibits this issue? Once we have that we should be able to diagnose.

[rochdev]

@ZivojnovicZarko Is this still an issue for you? And if it is, can you provide a reproduction snippet or steps to reproduce?

[mb21]

I'm working with @ZivojnovicZarko and yes, unfortunately it's still an issue for us. Sorry that we haven't gotten around to setting up a reproducible example yet, but the theory is that setting up a new Next.js project and running it on Node.js (with the specified versions), and then making a fetch request (using the built-in fetch of node.js 18.12) from next's getInitialProps (or getServerSideProps) will fail to generate an http-client trace.

[Qard]

The fetch API is not yet supported. It's not built on http.Client so you won't get http-client spans from it.

[mb21]

@Qard oh, interesting. Weird thing is that using plain fetch api with a express service on the same node version works for us. That's why we thought it must have to do with next.js...

[Qard]

Do you mean global fetch function or node-fetch? Also, Next.js has it's own custom patched version of fetch, if I recall correctly, so we'd need specific support for that, as far I can tell.

[mb21]

I'm saying that global fetch in node 18.12.1 works for us (not using node-fetch, which also used to work before we removed it).

Next.js has it's own custom patched version of fetch, if I recall correctly, so we'd need specific support for that, as far I can tell.

I see, that's what we were suspecting and what this issue is about then. Weird thing is that the patched version of fetch worked as well on node 16.17.0. (Note: we're using next 12, not next 13 which has the new app directory, RSC and even more patched fetch.)

[mb21]

Although interesting, console.log(fetch.toString()) in an empty node prompt and in a next.js getInitialProps function both print the same thing:

async function fetch(input, init = undefined) {
    emitExperimentalWarning('The Fetch API');
    return lazyUndici().fetch(input, init);
  }

so not sure our theory is actually correct...

[tlhunter]

It looks like this issue became a feature request for undici/fetch support. I'll close it as a duplicate of #1615 for now.