Files
capsule/pkg/webhook/owner_reference/patching.go
2020-08-04 16:30:28 +02:00

118 lines
3.7 KiB
Go

/*
Copyright 2020 Clastix Labs.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package owner_reference
import (
"context"
"encoding/json"
"net/http"
corev1 "k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/fields"
"k8s.io/apimachinery/pkg/runtime"
"k8s.io/apimachinery/pkg/types"
"sigs.k8s.io/controller-runtime/pkg/client"
"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
"sigs.k8s.io/controller-runtime/pkg/webhook/admission"
"github.com/clastix/capsule/api/v1alpha1"
"github.com/clastix/capsule/pkg/webhook"
)
// +kubebuilder:webhook:path=/mutate-v1-namespace-owner-reference,mutating=true,failurePolicy=fail,groups="",resources=namespaces,verbs=create,versions=v1,name=owner.namespace.capsule.clastix.io
type Webhook struct{}
func (o Webhook) GetHandler() webhook.Handler {
return &handler{}
}
func (o Webhook) GetName() string {
return "OwnerReference"
}
func (o Webhook) GetPath() string {
return "/mutate-v1-namespace-owner-reference"
}
type handler struct {
}
func (r *handler) OnCreate(ctx context.Context, req admission.Request, clt client.Client, decoder *admission.Decoder) admission.Response {
ns := &corev1.Namespace{}
if err := decoder.Decode(req, ns); err != nil {
return admission.Errored(http.StatusBadRequest, err)
}
if len(ns.ObjectMeta.Labels) > 0 {
ln, err := v1alpha1.GetTypeLabel(&v1alpha1.Tenant{})
if err != nil {
return admission.Errored(http.StatusBadRequest, err)
}
l, ok := ns.ObjectMeta.Labels[ln]
// assigning namespace to Tenant in case of label
if ok {
// retrieving the selected Tenant
t := &v1alpha1.Tenant{}
if err := clt.Get(ctx, types.NamespacedName{Name: l}, t); err != nil {
return admission.Errored(http.StatusBadRequest, err)
}
// Tenant owner must adhere to user that asked for NS creation
if t.Spec.Owner != req.UserInfo.Username {
return admission.Denied("Cannot assign the desired namespace to a non-owned Tenant")
}
// Patching the response
return r.patchResponseForOwnerRef(t, ns)
}
}
tl := &v1alpha1.TenantList{}
if err := clt.List(ctx, tl, client.MatchingFieldsSelector{
Selector: fields.OneTermEqualSelector(".spec.owner", req.UserInfo.Username),
}); err != nil {
return admission.Errored(http.StatusBadRequest, err)
}
if len(tl.Items) > 0 {
return r.patchResponseForOwnerRef(&tl.Items[0], ns)
}
return admission.Denied("You do not have any Tenant assigned: please, reach out the system administrators")
}
func (r *handler) OnDelete(ctx context.Context, req admission.Request, client client.Client, decoder *admission.Decoder) admission.Response {
return admission.Allowed("")
}
func (r *handler) OnUpdate(ctx context.Context, req admission.Request, client client.Client, decoder *admission.Decoder) admission.Response {
return admission.Denied("Capsule user cannot update a Namespace")
}
func (r *handler) patchResponseForOwnerRef(tenant *v1alpha1.Tenant, ns *corev1.Namespace) admission.Response {
scheme := runtime.NewScheme()
_ = v1alpha1.AddToScheme(scheme)
_ = corev1.AddToScheme(scheme)
o, _ := json.Marshal(ns.DeepCopy())
if err := controllerutil.SetControllerReference(tenant, ns, scheme); err != nil {
return admission.Errored(http.StatusInternalServerError, err)
}
c, _ := json.Marshal(ns)
return admission.PatchResponseFromRaw(o, c)
}