Proactively refresh tokens before they expire

[mattwiller]

In order to prevent errors around tokens becoming invalid, the SDK should pre-emptively refresh access tokens before making API calls rather than waiting for a 401 response from the Box API. This will necessitate some interface changes to the OAuth2 class, and will be a breaking change in the 2.x release.

[ikwyl6]

or have a function/call or ability to check if an existing refresh or access token is invalid. Then you know for sure it's invalid and can get a new one.

[stale[bot]]

This issue has been automatically marked as stale because it has not been updated in the last 30 days. It will be closed if no further activity occurs within the next 7 days. Feel free to reach out or mention Box SDK team member for further help and resources if they are needed.

[stale[bot]]

This issue has been automatically closed due to maximum period of being stale. Thank you for your contribution to Box Python SDK and feel free to open another PR/issue at any time.