@azure/openai - Additional OPTIONS request made before POST request for getChatCompletions call

[jamesmcroft]

• Package Name: @azure/openai
• Package Version: 1.0.0-beta.12
• Operating system: Windows 11
• nodejs
  • version: 20.12.1
• browser
  • name/version:
• typescript
  • version: 5.4.2
• Is the bug related to documentation in
  • README.md
  • source code documentation
  • SDK API docs on https://docs.microsoft.com

Describe the bug
A clear and concise description of what the bug is.

When calling the getChatCompletions function of an OpenAIClient, an OPTIONS call to the API is made before the POST call is successfully processed.

For most scenarios calling Azure OpenAI directly, this works fine. However, scenarios that implement proxies to multiple Azure OpenAI backend instances do not. This is because the OPTIONS request is not defined in the OpenAPI specification for the Azure OpenAI APIs. Those implementing the spec will not handle OPTIONS requests as is not expected.

Exploring the JS SDK, I cannot find where this request is being made as it is not clear in the OpenAI specific source that this is the case.

To confirm functionality across Azure OpenAI SDKs, the .NET SDK will only perform the POST request resulting in a successful response via a proxy.

To Reproduce
Steps to reproduce the behavior:

1. Create a new OpenAIClient with default Azure OpenAI configuration
2. Using a traffic monitoring tool (such as Fiddler), make a request using the OpenAIClient using the getChatCompletions function.

Notice that there are two requests made. The initial OPTIONS request, and the subsequent POST request.

Expected behavior
A clear and concise description of what you expected to happen.

Only the POST request should be made.

Screenshots
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Additional context
Add any other context about the problem here.

[github-actions]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @glharper.

[jamesmcroft]

Attempting to hijack the requests with a custom HttpClient implementation from the @azure/core-rest-pipeline library also does not work as expected.

I can assume that the OPTIONS request is part of a downstream function called by the default HTTP client provided by the core-rest-pipeline SDK.

[xirzec]

@jamesmcroft this is odd, I don't think we should be making OPTIONS requests in Node. I'd expect this to only happen in a browser due to CORS. Can you confirm the environment you're executing your code in is Node 20?