handles _thenUnwrap for OpenAI's custom APIPromise class

[josemussa]

What does this PR do?

Tracing is failing for requests that include a call to the OpenAI this.client.beta.chat.completions.parse method.

This happens because OpenAI uses a custom promise class. The Datadog team is already aware of this issue, as it was previously addressed for the OpenAI this.client.chat.completions.create method. I'm reusing that logic to resolve the current issue.

This PR implements the same unwrap logic and response handler that is used for the parse method, but for the _thenUnwrap method.

Motivation

When using the OpenAI Node SDK and calling await this.client.beta.chat.completions.parse, traces completely break.

This happens because OpenAI uses a custom promise. This issue was previously fixed for this.client.chat.completions.create (the non-beta version). To address this, I abstracted that fix and applied it to _thenUnwrap.

The issue is reported here openai/openai-node#1307

Plugin Checklist

• Unit tests.
• TypeScript definitions.
• TypeScript tests.
• API documentation.
• CircleCI jobs/workflows.
• Plugin is exported.

Additional Notes

[josemussa]

Hi @sabrenner, I saw that you’re the main author of this file—would you be open to reviewing this PR when you have a moment? Thanks a lot!

[sabrenner]

Hi @josemussa! Yes, I'll be taking a look at this today, thanks for the ping!

[sabrenner]

This change LGTM, although I'll refactor the test a bit. Unfortunately CI for community PRs isn't great here haha - I will cherry pick your commits into a new PR to run against CI and merge 🙌

just also wanna note as an FYI that since it's technically on the beta client, we generally won't be as quick to update support if its behavior changes at all from what we assume, and once the functionality that is supported here (I'm guessing structured output) is passed onto the official client, we'll advertise tracing through the official client instead.

[josemussa]

Thanks, @sabrenner! Appreciate you handling the CI situation and the refactor. Let me know if anything else is needed! 🚀

[sabrenner]

Hi @josemussa, the PR with the cherry picks has been merged! We should be tracing those beta chat completions now. Will follow up with the release it lands in (it might not be the next patch release, but probably 5.38.0 instead)

[josemussa]

Great news! Thank you @sabrenner 🙇