Guestbook Application Reference Implementation for Operator Builder

This repository uses two projects to construct an operator, based on the Kubernetes sample guestbook application.

• YAML Overlay Tool Used for taking the source manifests found in the Kubernetes documentation and injecting operator-builder workload markers to prepare for building an operator.
• Operator Builder Used for constructing a fully functional operator from source Kubernetes manifests that have been marked up for CRD customization.

How to use this repository

• Clone the repository

• Overlay the source manifests: cd .yot; yot -i yot.yaml

• Initialize the repository for Operator Builder:

# assuming you're in .yot still
cd ..
go mod init guestbook-app

operator-builder init \
    --workload-config .source/workload.yaml \
    --skip-go-version-check

• Build the guestbook operator:

operator-builder create api \
    --workload-config .source/workload.yaml \
    --controller \
    --resource

• Install the guestbook CRD to your cluster:

make install

• Run the operator locally for testing purposes:

make run

• Since the controller is occupying your terminal, you'll want to start up another terminal to install the sample CR to your Kubernetes cluster:

kubectl apply -f config/samples

You should now see the guestbook application get deployed into your cluster.

Please reference the operator-builder documentation for all the details on building more complex operators.