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.

Installation

The following script will install OLMv1 on a Kubernetes cluster. If you don't have one, you can deploy a Kubernetes cluster with KIND.

Caution

Operator-Controller depends on cert-manager. Running the following command may affect an existing installation of cert-manager and cause cluster instability.

The latest version of Operator Controller can be installed with the following command:

curl -L -s https://github.com/operator-framework/operator-controller/releases/latest/download/install.sh | bash -s

Getting Started with OLM v1

This quickstart procedure will guide you through the following processes:

• Deploying a catalog
• Installing, upgrading, or downgrading an extension
• Deleting catalogs and extensions

Create a Catalog

OLM v1 is designed to source content from an on-cluster catalog in the file-based catalog (FBC) format. These catalogs are deployed and configured through the ClusterCatalog resource. More information on adding catalogs can be found here.

The following example uses the official OperatorHub catalog that contains many different extensions to choose from. Note that this catalog contains packages designed to work with OLM v0, and that not all packages will work with OLM v1. More information on catalog exploration and content compatibility can be found here.

To create the catalog, run the following command:

# Create ClusterCatalog
kubectl apply -f - <<EOF
apiVersion: catalogd.operatorframework.io/v1alpha1
kind: ClusterCatalog
metadata:
  name: operatorhubio
spec:
  source:
    type: image
    image:
      ref: quay.io/operatorhubio/catalog:latest
      pollInterval: 10m
EOF

Once the catalog is unpacked successfully, its content will be available for installation.

# Wait for the ClusterCatalog to be unpacked
kubectl wait --for=condition=Unpacked=True clustercatalog/operatorhubio --timeout=60s

Install a Cluster Extension

For simplicity, the following example manifest includes all necessary resources to install the ArgoCD operator. The manifest includes installation namespace, installer service account and associated minimal set of RBAC permissions needed for installation, and the ClusterExtension resource, which specifies the name and version of the extension to install. More information on installing extensions can be found here.

# Apply the sample ClusterExtension. Manifest already includes
# namespace and adequately privileged service account
kubectl apply -f https://raw.githubusercontent.com/operator-framework/operator-controller/main/config/samples/olm_v1alpha1_clusterextension.yaml

Upgrade the Cluster Extension

To upgrade the installed extension, update the version field in the ClusterExtension resource. Note that there must be CRD compatibility between the versions being upgraded, and the target version must be compatible with OLM v1. More information on CRD upgrade safety can be found here, compatible with OLM v1. More information on CRD upgrade safety can be found here, and on the extension upgrade process here.

# Update to v0.11.0
kubectl patch clusterextension argocd --type='merge' -p '{"spec": {"source": {"catalog": {"version": "0.11.0"}}}}'

For information on the downgrade process, see here.

Uninstall the Cluster Extension

To uninstall an extension, delete the ClusterExtension resource. This will trigger the uninstallation process, which will remove all resources created by the extension. More information on uninstalling extensions can be found here.

# Delete cluster extension and residing namespace
kubectl delete clusterextension/argocd

Cleanup

Extension installation requires the creation of a namespace, an installer service account, and its RBAC. Once the extension is uninstalled, these resources can be cleaned up.

# Delete namespace, and by extension, the installer service account, Role, and RoleBinding
kubectl delete namespace argocd

# Delete installer service account cluster roles
kubectl delete clusterrole argocd-installer-clusterrole && kubectl delete clusterrole argocd-rbac-clusterrole

# Delete installer service account cluster role bindings
kuebctl delete clusterrolebinding argocd-installer-binding && kubectl delete clusterrolebinding argocd-rbac-binding

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.