Adding validation for openai api key

[adrianhensler]

Currently, if the OPENAI_API_KEY is missing or incorrect, the errors returned may be confusing for new users. I was going to add some validation, but wasn't sure the best place to do so. Using the provided OPENAI_API_KEY to make a call to return valid models seems like a good test.

This was my first thought; just adding it to main.py

Should it be elsewhere? Suggestions or comments before I go further? Thanks.

import sys
from backend.server import app
from dotenv import load_dotenv
import openai

load_dotenv()

def validate_openai_api_key(api_key):
    try:
        openai.api_key = api_key
        # Perform a 'free' API call to retrieve a list of available models
        models = openai.Model.list()
        if not models:
            raise Exception("API key is invalid or no models are available.")
        print("OpenAI API key is valid.")
    except openai.error.AuthenticationError:
        raise Exception("OpenAI API key is invalid.")
    except openai.error.OpenAIError as e:
        raise Exception(f"OpenAI API error: {str(e)}")
    except Exception as e:
        raise Exception(f"Unexpected error during API key validation: {str(e)}")

try:
    api_key = os.getenv("OPENAI_API_KEY")

    if not api_key:
        raise EnvironmentError("OPENAI_API_KEY environment variable not set.")
    else:
        print("OPENAI_API_KEY environment variable found.")

    validate_openai_api_key(api_key)

except EnvironmentError as env_err:
    print(f"Error: {env_err}")
    sys.exit(1)

except Exception as ex:
    print(f"An error occurred: {ex}")
    sys.exit(1)

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)```