Clarity over transient-error handling in Python clients

[Michael Robin (thelazydogsback)]

Hello. Referencing this: https://learn.microsoft.com/en-us/openapi/kiota/errors#transient-errors
I'm trying to glean info as to the exact behavior of the python clients, especially if/when/what exceptions are generated for status such as 429 and if there is any in-built retry behavior, or if not, what the proper pattern is for using tenacity with kiota to ensure retries don't happen for non-recoverable error-codes.
thanks

[Vincent Biret (baywet)]

Hi Michael Robin (@thelazydogsback)
Thank you for using kiota and for reaching out.

Here is the source for the retry handler

Another thing to consider are claims challenges

Overall a kiota client will only retry:

• 429's and 503's when the request body is rewindable, and no content-range request header is present.
• 401's when a www-authenticate header with claims is present.

Let us know if you have any additional comments or questions.

[Michael Robin (thelazydogsback)]

Thanks for the reply.
I notice that if I set a breakpoint in the retry_handler __init__() and send() that it never gets hit -- do I need to explicitly install this middleware?
As kiota returns a model object directly rather than a wrapped response, is an exception generated if the middleware isn't installed or all attempts fail?

[Vincent Biret (baywet)]

Thank you for the additional information.

It is in the default handlers that get instantiated when you create a request adapter/client. So unless you're creating a custom http client, or we have a bug somewhere, it should be part of the request chain.

If all attempts fail, it'll return the failed response, eventually the http request adapter will translate that response into an exception.
If the handler is absent, the initial failed response will be directly returned.

Let us know if you have any additional comments or questions.

[Michael Robin (thelazydogsback)]

Yes, as noted in other threads, I'm creating my own request adaptor and client and providing some custom subclasses so that I can do (a) auth over plain HTTP, and (b) properly serialize out plain ISO dates that have no time portion.
How do I install the default middleware manually?
Thanks - have a good weekend

[Vincent Biret (baywet)]

Simply look at the link I provided in my previous message and call that method.
You can then pass the result to the client. (Example in the same file)

Let us know if you have other questions)

[Michael Robin (thelazydogsback)]

So that the next person can find an answer directly:

        from kiota_http.kiota_client_factory import KiotaClientFactory
        # client = httpx.AsyncClient( ...
        client = KiotaClientFactory.create_with_default_middleware(client)