Error using StringIO in audio transcription

[leejarvis]

Hello,

According to the documentation for OpenAI::Resources::Audio::Transcriptions#create, the file parameter accepts StringIO. However, I'm unable to get this to work (similarly, it says it also accepts a String, but I can't get that to work either).

Here's an example:

require "openai"

file = File.open(ARGV[0])
stringio = StringIO.new(File.binread(ARGV[0]), "rb")

client = OpenAI::Client.new
transcription = client.audio.transcriptions.create(model: "gpt-4o-transcribe", file: stringio)

puts transcription.text

It works OK for the file object, but not the stringio object, which raises the following error:

{:url=>"https://api.openai.com/v1/audio/transcriptions", :status=>400, :body=>{:error=>{:message=>"Unsupported file format", :type=>"invalid_request_error", :param=>"file", :code=>"unsupported_value"}}} (OpenAI::Errors::BadRequestError)

Am I missing something or should this work?

The file I'm using is the wav sample here: https://www.kaggle.com/datasets/pavanelisetty/sample-audio-files-for-speech-recognition

Thank you

[leejarvis]

I got this to work by building an OpenAI::FilePart instance:

stringio = StringIO.new(File.binread(ARGV[0]), "rb")
file_part = OpenAI::FilePart.new(stringio, filename: "audio.wav", content_type: "audio/wav")
transcription = client.audio.transcriptions.create(model: "gpt-4o-transcribe", file_part: file_part)

Which is fine, but highlighting that this doesn't work like the documentation suggests it should. Looks like perhaps the filename and content type are explicitly required if there's no file object?