Skop: Simple Kubernetes Operators for Go

Skop is a lightweight framework for writing Kubernetes operators in Go. It:

• Tries to keep the amount of boilerplate code small.
• Doesn’t rely on code generation.
• Provides helpers for common reconciliation tasks.

Usage

Basically, writing an operator for a custom resource boils down to:

1. Defining the custom resource as a Go struct:

   type Test struct {
       metav1.ObjectMeta `json:"metadata"`
       Kind              string   `json:"kind"`
       APIVersion        string   `json:"apiVersion"`
       Spec              TestSpec `json:"spec"`
   }
   
   type TestSpec struct {
       Text string `json:"text"`
   }

2. Creating the operator:

   op := skop.New(
       skop.WithResource("example.com", "v1", "tests", &Test{}),
       skop.WithReconciler(skop.ReconcilerFunc(reconciler)),
   )

3. Writing the reconcile function:

   func reconciler(ctx context.Context, op *skop.Operator, res k8s.Resource) error {
       test := res.(*Test)
       deployment := makeDeployment(test)
       return reconcile.Deployment(ctx, op.Clientset(), deployment)
   }

4. Running the operator:

   go op.Run()

A complete, working example can be found in the example/ directory.

Who’s using Skop

• Hetzner Cloud is using Skop to deploy their services in production, staging, and development environments.

License

MIT