Merge pull request #3152 from RedbackThomson/inactive_workspaces

✨ Add inactive annotation to logicalcluster

pkg/server/config.go

@@ -445,6 +445,7 @@ func NewConfig(opts kcpserveroptions.CompletedOptions) (*Config, error) {
 		apiHandler = filters.WithWarningRecorder(apiHandler)
 
 		apiHandler = kcpfilters.WithAuditEventClusterAnnotation(apiHandler)
+		apiHandler = kcpfilters.WithBlockInactiveLogicalClusters(apiHandler, c.KcpSharedInformerFactory.Core().V1alpha1().LogicalClusters())
 
 		// Add a mux before the chain, for other handlers with their own handler chain to hook in. For example, when
 		// the virtual workspace server is running as part of kcp, it registers /services with the mux so it can handle

pkg/server/filters/filters.go

@@ -18,6 +18,7 @@ package filters
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -35,6 +36,9 @@ import (
 	kaudit "k8s.io/apiserver/pkg/audit"
 	"k8s.io/apiserver/pkg/endpoints/handlers/responsewriters"
 	"k8s.io/apiserver/pkg/endpoints/request"
+
+	corev1alpha1 "github.com/kcp-dev/kcp/sdk/apis/core/v1alpha1"
+	informersv1alpha1 "github.com/kcp-dev/kcp/sdk/client/informers/externalversions/core/v1alpha1"
 )
 
 type (
@@ -44,6 +48,10 @@ type (
 const (
 	workspaceAnnotation = "tenancy.kcp.io/workspace"
 
+	// inactiveAnnotation is the annotation denoting a logical cluster should be
+	// deemed unreachable.
+	inactiveAnnotation = "internal.kcp.io/inactive"
+
 	// clusterKey is the context key for the request namespace.
 	acceptHeaderContextKey acceptHeaderContextKeyType = iota
 )
@@ -78,6 +86,49 @@ func WithAuditEventClusterAnnotation(handler http.Handler) http.HandlerFunc {
 	})
 }
 
+// WithBlockInactiveLogicalClusters ensures that any requests to logical
+// clusters marked inactive are rejected.
+func WithBlockInactiveLogicalClusters(handler http.Handler, kcpClusterClient informersv1alpha1.LogicalClusterClusterInformer) http.HandlerFunc {
+	allowedPathPrefixes := []string{
+		"/openapi",
+		"/apis/core.kcp.io/v1alpha1/logicalclusters",
+	}
+
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		_, newURL, _, err := ClusterPathFromAndStrip(req)
+		if err != nil {
+			responsewriters.InternalError(w, req, err)
+			return
+		}
+
+		isException := false
+		for _, prefix := range allowedPathPrefixes {
+			if strings.HasPrefix(newURL.String(), prefix) {
+				isException = true
+			}
+		}
+
+		cluster := request.ClusterFrom(req.Context())
+		if cluster != nil && !cluster.Name.Empty() && !isException {
+			logicalCluster, err := kcpClusterClient.Cluster(cluster.Name).Lister().Get(corev1alpha1.LogicalClusterName)
+			if err == nil {
+				if ann, ok := logicalCluster.ObjectMeta.Annotations[inactiveAnnotation]; ok && ann == "true" {
+					responsewriters.ErrorNegotiated(
+						apierrors.NewForbidden(corev1alpha1.Resource("logicalclusters"), cluster.Name.String(), errors.New("logical cluster is marked inactive")),
+						errorCodecs, schema.GroupVersion{}, w, req,
+					)
+					return
+				}
+			} else if !apierrors.IsNotFound(err) {
+				responsewriters.InternalError(w, req, err)
+				return
+			}
+		}
+
+		handler.ServeHTTP(w, req)
+	})
+}
+
 // WithClusterScope reads a cluster name from the URL path and puts it into the context.
 // It also trims "/clusters/" prefix from the URL.
 func WithClusterScope(apiHandler http.Handler) http.HandlerFunc {