Type 2: include data about PAT expiry

Start at the sign_in method in server/endpoint/auth_endpoint.py and compare its authentication response handling with the linked Tableau REST API documentation. Trace the returned token-expiry value and determine how the optional threshold, warning, default, and callback should behave; done means near-expiry tokens produce the requested warning or callback with the API’s days:hours:seconds string.

Summary

When authenticating with a personal access token (PAT) a duration until the expiry of the token is returned by the login request.
This information is dropped by the python client, yet would be useful to have it logged as a warning when the expiration date is near.

Description

As users of the python client, we have automated some data-engineering tasks, and authenticate with PATs.
Since the PATs may be configured to expire after a given period of time, it is necessary to keep track of when tokens need to be renewed.

The time until expiry is available in the following REST Request:
https://help.tableau.com/current/api/rest_api/en-us/REST/rest_api_concepts_auth.htm#make-a-sign-in-request-with-a-personal-access-token

Since this request is already made as a part of the authentication process in the python client, I would like to extend the client to pass two optional parameters to the sign_in method:

• token_expiry_warning_threshold: Optional[int] = 60
• token_expiry_warning_callback: Optional[Callable[[str], None]]

The provided threshold should be an integer which represents days. If the token is set to expire in less days than in the threshold, a warning should be logged. I think 60 days is a sane default given the default expiration period is after 1 year.
A callable may also be provided which will be called with the string containing the time until expiry as received from the API. Its format is "days:hours:seconds".