How do I validate CRDs with webhooks?

To validate Custom Resource Definitions (CRDs) in Kubernetes using webhooks, you can create an admission webhook that listens to create and update requests for your CRDs. This process ensures that the objects conform to your expected validations before they are persisted in the cluster. Below is a simple example of how to set up a validating admission webhook in Go.

package main import ( "context" "encoding/json" "net/http" "os" admissionv1 "k8s.io/api/admission/v1" metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" "k8s.io/apiserver/pkg/admission" "k8s.io/apiserver/pkg/admission/plugin/webhook" "k8s.io/client-go/kubernetes/scheme" ) func validateCRD(w http.ResponseWriter, r *http.Request) { var admissionResponse admissionv1.AdmissionResponse // Decode the request var admissionReview admissionv1.AdmissionReview if err := json.NewDecoder(r.Body).Decode(&admissionReview); err != nil { admissionResponse.Allowed = false admissionResponse.Result = &metav1.Status{ Reason: "Failed to decode request", } writeResponse(w, admissionResponse) return } // Perform validation logic here // For demonstration, we allow all requests admissionResponse.Allowed = true // Write the admission response back writeResponse(w, admissionResponse) } func writeResponse(w http.ResponseWriter, admissionResponse admissionv1.AdmissionResponse) { admissionReviewResponse := admissionv1.AdmissionReview{ Response: &admissionResponse, } responseBytes, _ := json.Marshal(admissionReviewResponse) w.Write(responseBytes) } func main() { http.HandleFunc("/validate", validateCRD) port := os.Getenv("PORT") if port == "" { port = "8080" } http.ListenAndServe(":"+port, nil) }

CRD validation Kubernetes webhooks admission webhook Go programming Kubernetes development

Related Questions

How do I avoid rehashing overhead with std::set in multithreaded code?

How do I find elements with custom comparators with std::set for embedded targets?

How do I erase elements while iterating with std::set for embedded targets?

How do I provide stable iteration order with std::unordered_map for large datasets?

How do I reserve capacity ahead of time with std::unordered_map for large datasets?

How do I erase elements while iterating with std::unordered_map in multithreaded code?

How do I provide stable iteration order with std::map for embedded targets?

How do I provide stable iteration order with std::map in multithreaded code?

How do I avoid rehashing overhead with std::map in performance-sensitive code?

How do I merge two containers efficiently with std::map for embedded targets?