diff --git a/AGENTS.md b/AGENTS.md new file mode 100644 index 0000000..224fb6f --- /dev/null +++ b/AGENTS.md @@ -0,0 +1,285 @@ +# valkey-operator - AI Agent Guide + +## Project Structure + +**Single-group layout (default):** +``` +cmd/main.go Manager entry (registers controllers/webhooks) +api//*_types.go CRD schemas (+kubebuilder markers) +api//zz_generated.* Auto-generated (DO NOT EDIT) +internal/controller/* Reconciliation logic +internal/webhook/* Validation/defaulting (if present) +config/crd/bases/* Generated CRDs (DO NOT EDIT) +config/rbac/role.yaml Generated RBAC (DO NOT EDIT) +config/samples/* Example CRs (edit these) +Makefile Build/test/deploy commands +PROJECT Kubebuilder metadata Auto-generated (DO NOT EDIT) +``` + +**Multi-group layout** (for projects with multiple API groups): +``` +api///*_types.go CRD schemas by group +internal/controller//* Controllers by group +internal/webhook///* Webhooks by group and version (if present) +``` + +Multi-group layout organizes APIs by group name (e.g., `batch`, `apps`). Check the `PROJECT` file for `multigroup: true`. + +**To convert to multi-group layout:** +1. Run: `kubebuilder edit --multigroup=true` +2. Move APIs: `mkdir -p api/ && mv api/ api//` +3. Move controllers: `mkdir -p internal/controller/ && mv internal/controller/*.go internal/controller//` +4. Move webhooks (if present): `mkdir -p internal/webhook/ && mv internal/webhook/ internal/webhook//` +5. Update import paths in all files +6. Fix `path` in `PROJECT` file for each resource +7. Update test suite CRD paths (add one more `..` to relative paths) + +## Critical Rules + +### Never Edit These (Auto-Generated) +- `config/crd/bases/*.yaml` - from `make manifests` +- `config/rbac/role.yaml` - from `make manifests` +- `config/webhook/manifests.yaml` - from `make manifests` +- `**/zz_generated.*.go` - from `make generate` +- `PROJECT` - from `kubebuilder [OPTIONS]` + +### Never Remove Scaffold Markers +Do NOT delete `// +kubebuilder:scaffold:*` comments. CLI injects code at these markers. + +### Keep Project Structure +Do not move files around. The CLI expects files in specific locations. + +### Always Use CLI Commands +Always use `kubebuilder create api` and `kubebuilder create webhook` to scaffold. Do NOT create files manually. + +### E2E Tests Require an Isolated Kind Cluster +The e2e tests are designed to validate the solution in an isolated environment (similar to GitHub Actions CI). +Ensure you run them against a dedicated [Kind](https://kind.sigs.k8s.io/) cluster (not your “real” dev/prod cluster). + +## After Making Changes + +**After editing `*_types.go` or markers:** +``` +make manifests # Regenerate CRDs/RBAC from markers +make generate # Regenerate DeepCopy methods +``` + +**After editing `*.go` files:** +``` +make lint-fix # Auto-fix code style +make test # Run unit tests +``` + +## CLI Commands Cheat Sheet + +### Create API (your own types) +```bash +kubebuilder create api --group --version --kind +``` + +### Deploy Image Plugin (scaffold to deploy/manage ANY container image) + +Generate a controller that deploys and manages a container image (nginx, redis, memcached, your app, etc.): + +```bash +# Example: deploying memcached +kubebuilder create api --group example.com --version v1alpha1 --kind Memcached \ + --image=memcached:alpine \ + --plugins=deploy-image.go.kubebuilder.io/v1-alpha +``` + +Scaffolds good-practice code: reconciliation logic, status conditions, finalizers, RBAC. Use as a reference implementation. + + +### Create Webhooks +```bash +# Validation + defaulting +kubebuilder create webhook --group --version --kind \ + --defaulting --programmatic-validation + +# Conversion webhook (for multi-version APIs) +kubebuilder create webhook --group --version v1 --kind \ + --conversion --spoke v2 +``` + +### Controller for Core Kubernetes Types +```bash +# Watch Pods +kubebuilder create api --group core --version v1 --kind Pod \ + --controller=true --resource=false + +# Watch Deployments +kubebuilder create api --group apps --version v1 --kind Deployment \ + --controller=true --resource=false +``` + +### Controller for External Types (e.g., from other operators) + +Watch resources from external APIs (cert-manager, Argo CD, Istio, etc.): + +```bash +# Example: watching cert-manager Certificate resources +kubebuilder create api \ + --group cert-manager --version v1 --kind Certificate \ + --controller=true --resource=false \ + --external-api-path=github.com/cert-manager/cert-manager/pkg/apis/certmanager/v1 \ + --external-api-domain=io \ + --external-api-module=github.com/cert-manager/cert-manager +``` + +**Note:** Use `--external-api-module=@` only if you need a specific version. Otherwise, omit `@` to use what's in go.mod. + +### Webhook for External Types + +```bash +# Example: validating external resources +kubebuilder create webhook \ + --group cert-manager --version v1 --kind Issuer \ + --defaulting \ + --external-api-path=github.com/cert-manager/cert-manager/pkg/apis/certmanager/v1 \ + --external-api-domain=io \ + --external-api-module=github.com/cert-manager/cert-manager +``` + +## Testing & Development + +```bash +make test # Run unit tests (uses envtest: real K8s API + etcd) +make run # Run locally (uses current kubeconfig context) +``` + +Tests use **Ginkgo + Gomega** (BDD style). Check `suite_test.go` for setup. + +## Deployment Workflow + +```bash +# 1. Regenerate manifests +make manifests generate + +# 2. Build & deploy +export IMG=/:tag +make docker-build docker-push IMG=$IMG # Or: kind load docker-image $IMG --name +make deploy IMG=$IMG + +# 3. Test +kubectl apply -k config/samples/ + +# 4. Debug +kubectl logs -n -system deployment/-controller-manager -c manager -f +``` + +### API Design + +**Key markers for** `api//*_types.go`: + +```go +// +kubebuilder:object:root=true +// +kubebuilder:subresource:status +// +kubebuilder:resource:scope=Namespaced +// +kubebuilder:printcolumn:name="Status",type=string,JSONPath=".status.conditions[?(@.type=='Ready')].status" + +// On fields: +// +kubebuilder:validation:Required +// +kubebuilder:validation:Minimum=1 +// +kubebuilder:validation:MaxLength=100 +// +kubebuilder:validation:Pattern="^[a-z]+$" +// +kubebuilder:default="value" +``` + +- **Use** `metav1.Condition` for status (not custom string fields) +- **Use predefined types**: `metav1.Time` instead of `string` for dates +- **Follow K8s API conventions**: Standard field names (`spec`, `status`, `metadata`) + +### Controller Design + +**RBAC markers in** `internal/controller/*_controller.go`: + +```go +// +kubebuilder:rbac:groups=mygroup.example.com,resources=mykinds,verbs=get;list;watch;create;update;patch;delete +// +kubebuilder:rbac:groups=mygroup.example.com,resources=mykinds/status,verbs=get;update;patch +// +kubebuilder:rbac:groups=mygroup.example.com,resources=mykinds/finalizers,verbs=update +// +kubebuilder:rbac:groups=events.k8s.io,resources=events,verbs=create;patch +// +kubebuilder:rbac:groups=apps,resources=deployments,verbs=get;list;watch;create;update;patch;delete +``` + +**Implementation rules:** +- **Idempotent reconciliation**: Safe to run multiple times +- **Re-fetch before updates**: `r.Get(ctx, req.NamespacedName, obj)` before `r.Update` to avoid conflicts +- **Structured logging**: `log := log.FromContext(ctx); log.Info("msg", "key", val)` +- **Owner references**: Enable automatic garbage collection (`SetControllerReference`) +- **Watch secondary resources**: Use `.Owns()` or `.Watches()`, not just `RequeueAfter` +- **Finalizers**: Clean up external resources (buckets, VMs, DNS entries) + +### Webhooks +- **Create all types together**: `--defaulting --programmatic-validation --conversion` +- **When`--force`is used**: Backup custom logic first, then restore after scaffolding +- **For multi-version APIs**: Use hub-and-spoke pattern (`--conversion --spoke v2`) + - Hub version: Usually oldest stable version (v1) + - Spoke versions: Newer versions that convert to/from hub (v2, v3) + - Example: `--group crew --version v1 --kind Captain --conversion --spoke v2` (v1 is hub, v2 is spoke) + +### Learning from Examples + +The **deploy-image plugin** scaffolds a complete controller following good practices. Use it as a reference implementation: + +```bash +kubebuilder create api --group example --version v1alpha1 --kind MyApp \ + --image= --plugins=deploy-image.go.kubebuilder.io/v1-alpha +``` + +Generated code includes: status conditions (`metav1.Condition`), finalizers, owner references, events, idempotent reconciliation. + +## Distribution Options + +### Option 1: YAML Bundle (Kustomize) + +```bash +# Generate dist/install.yaml from Kustomize manifests +make build-installer IMG=/:tag +``` + +**Key points:** +- The `dist/install.yaml` is generated from Kustomize manifests (CRDs, RBAC, Deployment) +- Commit this file to your repository for easy distribution +- Users only need `kubectl` to install (no additional tools required) + +**Example:** Users install with a single command: +```bash +kubectl apply -f https://raw.githubusercontent.com////dist/install.yaml +``` + +### Option 2: Helm Chart + +```bash +kubebuilder edit --plugins=helm/v2-alpha # One-time, generates dist/chart/ +# Users install: helm install my-release ./dist/chart/ --namespace --create-namespace +``` + +**Important:** If you add webhooks or modify manifests after initial chart generation: +1. Backup any customizations in `dist/chart/values.yaml` and `dist/chart/manager/manager.yaml` +2. Re-run: `kubebuilder edit --plugins=helm/v2-alpha --force` +3. Manually restore your custom values from the backup + +### Publish Container Image + +```bash +export IMG=/: +make docker-build docker-push IMG=$IMG +``` + +## References + +### Essential Reading +- **Kubebuilder Book**: https://book.kubebuilder.io (comprehensive guide) +- **controller-runtime FAQ**: https://github.com/kubernetes-sigs/controller-runtime/blob/main/FAQ.md (common patterns and questions) +- **Good Practices**: https://book.kubebuilder.io/reference/good-practices.html (why reconciliation is idempotent, status conditions, etc.) + +### API Design & Implementation +- **API Conventions**: https://github.com/kubernetes/community/blob/master/contributors/devel/sig-architecture/api-conventions.md +- **Operator Pattern**: https://kubernetes.io/docs/concepts/extend-kubernetes/operator/ +- **Markers Reference**: https://book.kubebuilder.io/reference/markers.html + +### Tools & Libraries +- **controller-runtime**: https://github.com/kubernetes-sigs/controller-runtime +- **controller-tools**: https://github.com/kubernetes-sigs/controller-tools +- **Kubebuilder Repo**: https://github.com/kubernetes-sigs/kubebuilder \ No newline at end of file