One of the best features of CouchDB is its change feed which allows us to get a feed of the changes happening on our database. It’s also possible to have a serverless function (examples are for IBM Cloud Functions but should also work for Apache OpenWhisk) that fires in response to activity on that change feed. I have a database of events that I want to react to when they happen, but the change feed doesn’t include the actual document that was added – but you can add one of the built-in functions to a sequence to make that happen. This post will show how to achieve this by wiring up a built-in action to fetch the document with another action of our own that then handles the data. Continue reading →