React to Database Changes with OpenWhisk Actions

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

Multiple Search Keys in CouchDB

I work quite a bit with CouchDB (Cloudant, a hosted CouchDB solution, is part of Bluemix, IBM's cloud platform - and I work for IBM so I get to use this as much as I like) and today I found a feature I hadn't seen before. I struggled to find the docs, so I thought I'd post my working example here in case anyone else is solving a similar problem: wanting to use more than one set of key ranges when filtering a CouchDB view. Continue reading