operator-controller

README

operator-controller

The operator-controller is the central component of Operator Lifecycle Manager (OLM) v1. It extends Kubernetes with an API through which users can install extensions.

Mission

OLM’s purpose is to provide APIs, controllers, and tooling that support the packaging, distribution, and lifecycling of Kubernetes extensions. It aims to:

• align with Kubernetes designs and user assumptions
• provide secure, high-quality, and predictable user experiences centered around declarative GitOps concepts
• give cluster admins the minimal necessary controls to build their desired cluster architectures and to have ultimate control

Overview

OLM v1 is the follow-up to OLM v0, located here.

OLM v1 consists of two different components:

• operator-controller (this repository)
• catalogd

For a more complete overview of OLM v1 and how it differs from OLM v0, see our overview.

Getting Started

You’ll need a Kubernetes cluster to run against. You can use KIND to get a local cluster for testing, or run against a remote cluster.

[!NOTE] Your controller will automatically use the current context in your kubeconfig file (i.e. whatever cluster kubectl cluster-info shows).

Additional setup on Macintosh computers

On Macintosh computers some additional setup is necessary to install and configure compatible tooling.

Install Homebrew and tools

Follow the instructions to installing Homebrew and then execute the following to install tools:

brew install bash gnu-tar gsed

Configure your shell

Modify your login shell's PATH to prefer the new tools over those in the existing environment. This example should work either with zsh (in $HOME/.zshrc) or bash (in $HOME/.bashrc):

for bindir in `find $(brew --prefix)/opt -type d -follow -name gnubin -print`
do
  export PATH=$bindir:$PATH
done

Running on the cluster

1. Install Instances of Custom Resources:

kubectl apply -f config/samples/

1. Build and push your image to the location specified by IMG:

make docker-build docker-push IMG=<some-registry>/operator-controller:tag

1. Deploy the controller to the cluster with the image specified by IMG:

make deploy IMG=<some-registry>/operator-controller:tag

Uninstall CRDs

To delete the CRDs from the cluster:

make uninstall

Undeploy controller

To undeploy the controller from the cluster:

make undeploy

Contributing

Refer to CONTRIBUTING.md for more information.

How it works

This project aims to follow the Kubernetes Operator pattern.

It uses Controllers which provide a reconcile function responsible for synchronizing resources until the desired state is reached on the cluster.

Test It Out

Install the CRDs and the operator-controller into a new KIND cluster:

make run

This will build a local container image of the operator-controller, create a new KIND cluster and then deploy onto that cluster. This will also deploy the catalogd and cert-manager dependencies.

Modifying the API definitions

If you are editing the API definitions, generate the manifests such as CRs or CRDs using:

make manifests

NOTE: Run make help for more information on all potential make targets.

More information can be found via the Kubebuilder Documentation.

License

Copyright 2022-2024.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.