development

Kubernetes Operator

Operator SDK

Version: v1.15.0

Used commands:

1. Initialize the project.

   operator-sdk init --domain nakamasato.com --repo github.com/nakamasato/mysql-operator
   

2. Create API resources and their controllers.

   operator-sdk create api --group mysql --version v1alpha1 --kind MySQL --resource --controller
   operator-sdk create api --group mysql --version v1alpha1 --kind MySQLUser --resource --controller
   

3. Create admission webhook.

   1. --defaulting (not used)
   2. --conversion

      operator-sdk create webhook --group mysql --version v1alpha1 --kind MySQL --conversion --programmatic-validation
      

Finalizers

• https://book.kubebuilder.io/reference/using-finalizers.html
• https://zdyxry.github.io/2019/09/13/Kubernetes-%E5%AE%9E%E6%88%98-Operator-Finalizers/
• https://sdk.operatorframework.io/docs/building-operators/golang/advanced-topics/

Webhook

• https://kubernetes.io/docs/reference/access-authn-authz/extensible-admission-controllers/
• https://docs.giantswarm.io/advanced/custom-admission-controller/
• https://sdk.operatorframework.io/docs/building-operators/golang/webhook
• https://zoetrope.github.io/kubebuilder-training/controller-runtime/webhook.html

Testing

• KUbernetes Testing TooL (kuttl)
• Ginkgo (A Golang BDD Testing Framework)
• Gomega (Ginkgo's preferred matcher library)

MySQL

• https://github.com/go-sql-driver/mysql/wiki/Examples