| /* |
| Copyright 2016 The Kubernetes Authors. |
| |
| 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 antiaffinity |
| |
| import ( |
| "fmt" |
| "io" |
| |
| apierrors "k8s.io/apimachinery/pkg/api/errors" |
| "k8s.io/apiserver/pkg/admission" |
| api "k8s.io/kubernetes/pkg/apis/core" |
| kubeletapis "k8s.io/kubernetes/pkg/kubelet/apis" |
| ) |
| |
| const PluginName = "LimitPodHardAntiAffinityTopology" |
| |
| // Register registers a plugin |
| func Register(plugins *admission.Plugins) { |
| plugins.Register(PluginName, func(config io.Reader) (admission.Interface, error) { |
| return NewInterPodAntiAffinity(), nil |
| }) |
| } |
| |
| // Plugin contains the client used by the admission controller |
| type Plugin struct { |
| *admission.Handler |
| } |
| |
| var _ admission.ValidationInterface = &Plugin{} |
| |
| // NewInterPodAntiAffinity creates a new instance of the LimitPodHardAntiAffinityTopology admission controller |
| func NewInterPodAntiAffinity() *Plugin { |
| return &Plugin{ |
| Handler: admission.NewHandler(admission.Create, admission.Update), |
| } |
| } |
| |
| // Validate will deny any pod that defines AntiAffinity topology key other than kubeletapis.LabelHostname i.e. "kubernetes.io/hostname" |
| // in requiredDuringSchedulingRequiredDuringExecution and requiredDuringSchedulingIgnoredDuringExecution. |
| func (p *Plugin) Validate(attributes admission.Attributes) (err error) { |
| // Ignore all calls to subresources or resources other than pods. |
| if len(attributes.GetSubresource()) != 0 || attributes.GetResource().GroupResource() != api.Resource("pods") { |
| return nil |
| } |
| pod, ok := attributes.GetObject().(*api.Pod) |
| if !ok { |
| return apierrors.NewBadRequest("Resource was marked with kind Pod but was unable to be converted") |
| } |
| affinity := pod.Spec.Affinity |
| if affinity != nil && affinity.PodAntiAffinity != nil { |
| var podAntiAffinityTerms []api.PodAffinityTerm |
| if len(affinity.PodAntiAffinity.RequiredDuringSchedulingIgnoredDuringExecution) != 0 { |
| podAntiAffinityTerms = affinity.PodAntiAffinity.RequiredDuringSchedulingIgnoredDuringExecution |
| } |
| // TODO: Uncomment this block when implement RequiredDuringSchedulingRequiredDuringExecution. |
| //if len(affinity.PodAntiAffinity.RequiredDuringSchedulingRequiredDuringExecution) != 0 { |
| // podAntiAffinityTerms = append(podAntiAffinityTerms, affinity.PodAntiAffinity.RequiredDuringSchedulingRequiredDuringExecution...) |
| //} |
| for _, v := range podAntiAffinityTerms { |
| if v.TopologyKey != kubeletapis.LabelHostname { |
| return apierrors.NewForbidden(attributes.GetResource().GroupResource(), pod.Name, fmt.Errorf("affinity.PodAntiAffinity.RequiredDuringScheduling has TopologyKey %v but only key %v is allowed", v.TopologyKey, kubeletapis.LabelHostname)) |
| } |
| } |
| } |
| return nil |
| } |