Measure number of active users over various periods

[danielballan]

JupyterHub added Prometheus gauge metrics giving the number of users active over the last {24h, 7d, 30d}.

jupyterhub_active_users{period="24h"} 1.0
jupyterhub_active_users{period="7d"} 494.0
jupyterhub_active_users{period="30d"} 3140.0

A Prometheus server polling these metrics over time will be able to show trends in use. JupyterHub expects server admins to use this to justify resources for their deployments.

Adding similar metrics to Tiled would be useful to give us a sense of Tiled adoption at NSLS2 (or elsewhere).

With our auth database we already know the total number of users that have ever logged in, and we track the time datetime of each user’s latest activity, but we do not have access to trends over time.