Kubernetes Operators

Chapter 4. The Operator Framework

There is inevitable complexity in developing an Operator, and in managing its distribution, deployment, and lifecycle. The Red Hat Operator Framework makes it simpler to create and distribute Operators. It makes building Operators easier with a software development kit (SDK) that automates much of the repetitive implementation work. The Framework also provides mechanisms for deploying and managing Operators. Operator Lifecycle Manager (OLM) is an Operator that installs, manages, and upgrades other Operators. Operator Metering is a metrics system that accounts for Operators’ use of cluster resources. This chapter gives an overview of these three key parts of the Framework to prepare you to use those tools to build and distribute an example Operator. Along the way, you’ll install the operator-sdk command-line tool, the primary interface to SDK features.

Operator Framework Origins

The Operator SDK builds atop the Kubernetes controller-runtime, a set of libraries providing essential Kubernetes controller routines in the Go programming language. As part of the Operator Framework, the SDK provides integration points for distributing and managing Operators with OLM, and measuring them with Operator Metering. The SDK and the entire Red Hat Operator Framework are open source with contributors from throughout the community and other organizations, and are in the process of being donated to the vendor-neutral Cloud Native Computing Foundation, home to Kubernetes ...