By John Beynon
When Heroku Postgres dataclips first appeared I remembered thinking that they were pretty cool but was struggling to find a use case for them.
More recently, my opinion has changed to just how awesome they are. Take for example a recent case where for whatever reason a Heroku worker hadn't been running for several weeks so the delayed job queue size was quite large.
With dataclips this is quite simple to monitor and catch in the future.
Define a dataclip which does a count of the delayed_jobs table size
Use a service like Pingdom to watch the output of the dataclip and if the returned content is not a count of 0 then report it. With Pingdom you can set how long a site could be down so for example setting it to 5 minutes would give the worker plenty of time to process the queue.
This is only one use of dataclips,