The Operator Framework was announced at KubeCon 2018 as an open source toolkit for managing Kubernetes native applications. The Operator SDK is a part of this framework, and it simplifies operator development by providing higher level API abstractions and code generation. The Operator Framework and its environment toolset is open source and community maintained with the control of CoreOS.

In this chapter, the Operator SDK from the Operator Framework has been selected to be used since SDK abstracts many low-level operations such as work queues, handler registrations, and informer management. With these abstractions, it is easier to handle Observe and Act parts with the packages from the SDK so that we can focus on the Analyze part.

In the following section, the complete life cycle of operator development is covered with the following main steps:

• Create an operator project: For the WeatherReport custom resource, an operator project in the Go language is created by using the Operator Framework SDK CLI.
• Define custom resource specification: The specification of the WeatherReport custom resource is defined in Go.
• Implement handler logic: The manual operations needed for weather report collection are implemented in Go.
• Build operator: The operator project is built using the Operator Framework SDK CLI.
• Deploy operator: The operator is deployed to the cluster, and it is tested by creating custom resources.