Invoking functions
This section describes the internal flow of how OpenWhisk invokes its actions. We will learn how to create (or register) a Docker container as an OpenWhisk action and how to invoke it.
Invocation flows
As OpenWhisk is an event-driven platform, any kind of event fired to it could be intercepted and interpreted. However, in this example, we will show you only the event triggered by sending a direct request to the gateway.
The invocation flow starts with an invocation request in the form of an HTTP-based request and is sent to the API gateway. For example, we can use the wsk CLI to initiate this kind of request. After the API gateway receives the request, it will forward that call to a controller behind it.
One of the most important components of OpenWhisk is the controller. The controller is a component written in Scala using the infamous framework Akka and Spray to implement a set of REST APIs. The controller accepts all kinds of requests; if it accepts a POST request, it will...