OpenWhisk – concepts and features

Apache OpenWhisk calls itself “an open-source, distributed serverless platform that executes functions (fx) in response to events at any scale.” OpenWhisk manages the platform, its scaling, and other operational aspects, freeing the developer to do what they do best: deliver business-critical applications. In this case, they would be serverless applications, though. The fundamental programming model of OpenWhisk is that the developers can write business logic as a function code in any of the programming languages supported. These functions are then invoked in response to events or schedules.

Let us look at the core concepts and building blocks of this programming model:

Figure 8.1 – OpenWhisk programming model

Now let us look into these entities in detail.

Actions and action chains

OpenWhisk is a FaaS platform, and within it, the function is referred to as an action. This is the computation...