I have a system in which a container is created every hour and I want to get an alert when a container is not created for a certain period of time from Prometheus or Grafana. Is there anyway to get a count of containers created in last let say X-hr and send an alert if the count of containers are less? The containers have a name template like : 2019-month-date-hour
Eg: 2019-5-11-23

I tried to use this query to get the count of containers created in a month count(count(container_last_seen{container_name=~"2019-5.*", namespace=$namespace}) by (container_name)) but not able to set grafana alert on this query for a period of time.