Handle error when str passed to /v1/audio/transcriptions

[hmellor]

Solves part of #17038

Server side:

INFO:     127.0.0.1:42508 - "POST /v1/audio/transcriptions HTTP/1.1" 422 Unprocessable Entity

Client side:

$ curl -X POST -H 'Content-Type: application/x-www-form-urlencoded' -d file=b%27%27 --insecure http://127.0.0.1:8000/v1/audio/transcriptions
{"detail":"Unsupported type for 'file'. Audio file should be a 'fastapi.UploadFile' object, not 'str'."}

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[DarkLight1337]

Is this consistent with what you get if you send a string to the actual OpenAI API?

[hmellor]

https://platform.openai.com/docs/guides/speech-to-text looks like it actually wants an open file handle, I could update the message to say that?

[DarkLight1337]

Yeah let's keep the message similar to the actual OpenAI API

[russellb]

lgtm

[russellb]

not sure why pre-commit fails on a file you didn't change, but your change lgtm

A test would be ideal, but I won't block on it

[hmellor]

#17864 (comment)