kubernetes/pkg/registry/pod/etcd/etcd.go
2015-03-16 14:22:01 -04:00

211 lines
7.1 KiB
Go

/*
Copyright 2014 Google Inc. All rights reserved.
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 etcd
import (
"fmt"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
etcderr "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors/etcd"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api/rest"
"github.com/GoogleCloudPlatform/kubernetes/pkg/fields"
"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
"github.com/GoogleCloudPlatform/kubernetes/pkg/registry/generic"
etcdgeneric "github.com/GoogleCloudPlatform/kubernetes/pkg/registry/generic/etcd"
"github.com/GoogleCloudPlatform/kubernetes/pkg/registry/pod"
"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
"github.com/GoogleCloudPlatform/kubernetes/pkg/tools"
"github.com/GoogleCloudPlatform/kubernetes/pkg/watch"
)
// rest implements a RESTStorage for pods against etcd
type REST struct {
store *etcdgeneric.Etcd
}
// NewREST returns a RESTStorage object that will work against pods.
func NewREST(h tools.EtcdHelper) (*REST, *BindingREST, *StatusREST) {
prefix := "/registry/pods"
store := &etcdgeneric.Etcd{
NewFunc: func() runtime.Object { return &api.Pod{} },
NewListFunc: func() runtime.Object { return &api.PodList{} },
KeyRootFunc: func(ctx api.Context) string {
return etcdgeneric.NamespaceKeyRootFunc(ctx, prefix)
},
KeyFunc: func(ctx api.Context, name string) (string, error) {
return etcdgeneric.NamespaceKeyFunc(ctx, prefix, name)
},
ObjectNameFunc: func(obj runtime.Object) (string, error) {
return obj.(*api.Pod).Name, nil
},
PredicateFunc: func(label labels.Selector, field fields.Selector) generic.Matcher {
return pod.MatchPod(label, field)
},
EndpointName: "pods",
Helper: h,
}
statusStore := *store
bindings := &podLifecycle{}
store.CreateStrategy = pod.Strategy
store.UpdateStrategy = pod.Strategy
store.AfterUpdate = bindings.AfterUpdate
store.ReturnDeletedObject = true
store.AfterDelete = bindings.AfterDelete
statusStore.UpdateStrategy = pod.StatusStrategy
return &REST{store: store}, &BindingREST{store: store}, &StatusREST{store: &statusStore}
}
// WithPodStatus returns a rest object that decorates returned responses with extra
// status information.
func (r *REST) WithPodStatus(cache pod.PodStatusGetter) *REST {
store := *r.store
store.Decorator = pod.PodStatusDecorator(cache)
store.AfterDelete = rest.AllFuncs(store.AfterDelete, pod.PodStatusReset(cache))
return &REST{store: &store}
}
// New returns a new object
func (r *REST) New() runtime.Object {
return r.store.NewFunc()
}
// NewList returns a new list object
func (r *REST) NewList() runtime.Object {
return r.store.NewListFunc()
}
// List obtains a list of pods with labels that match selector.
func (r *REST) List(ctx api.Context, label labels.Selector, field fields.Selector) (runtime.Object, error) {
return r.store.List(ctx, label, field)
}
// Watch begins watching for new, changed, or deleted pods.
func (r *REST) Watch(ctx api.Context, label labels.Selector, field fields.Selector, resourceVersion string) (watch.Interface, error) {
return r.store.Watch(ctx, label, field, resourceVersion)
}
// Get gets a specific pod specified by its ID.
func (r *REST) Get(ctx api.Context, name string) (runtime.Object, error) {
return r.store.Get(ctx, name)
}
// Create creates a pod based on a specification.
func (r *REST) Create(ctx api.Context, obj runtime.Object) (runtime.Object, error) {
return r.store.Create(ctx, obj)
}
// Update changes a pod specification.
func (r *REST) Update(ctx api.Context, obj runtime.Object) (runtime.Object, bool, error) {
return r.store.Update(ctx, obj)
}
// Delete deletes an existing pod specified by its ID.
func (r *REST) Delete(ctx api.Context, name string) (runtime.Object, error) {
return r.store.Delete(ctx, name)
}
// ResourceLocation returns a pods location from its HostIP
func (r *REST) ResourceLocation(ctx api.Context, name string) (string, error) {
return pod.ResourceLocation(r, ctx, name)
}
// BindingREST implements the REST endpoint for binding pods to nodes when etcd is in use.
type BindingREST struct {
store *etcdgeneric.Etcd
}
func (r *BindingREST) New() runtime.Object {
return &api.Binding{}
}
// Create ensures a pod is bound to a specific host.
func (r *BindingREST) Create(ctx api.Context, obj runtime.Object) (out runtime.Object, err error) {
binding := obj.(*api.Binding)
// TODO: move me to a binding strategy
if len(binding.Target.Kind) != 0 && (binding.Target.Kind != "Node" && binding.Target.Kind != "Minion") {
return nil, errors.NewInvalid("binding", binding.Name, errors.ValidationErrorList{errors.NewFieldInvalid("to.kind", binding.Target.Kind, "must be empty, 'Node', or 'Minion'")})
}
if len(binding.Target.Name) == 0 {
return nil, errors.NewInvalid("binding", binding.Name, errors.ValidationErrorList{errors.NewFieldRequired("to.name", binding.Target.Name)})
}
err = r.assignPod(ctx, binding.Name, binding.Target.Name)
err = etcderr.InterpretCreateError(err, "binding", "")
out = &api.Status{Status: api.StatusSuccess}
return
}
// setPodHostTo sets the given pod's host to 'machine' iff it was previously 'oldMachine'.
// Returns the current state of the pod, or an error.
func (r *BindingREST) setPodHostTo(ctx api.Context, podID, oldMachine, machine string) (finalPod *api.Pod, err error) {
podKey, err := r.store.KeyFunc(ctx, podID)
if err != nil {
return nil, err
}
err = r.store.Helper.AtomicUpdate(podKey, &api.Pod{}, false, func(obj runtime.Object) (runtime.Object, uint64, error) {
pod, ok := obj.(*api.Pod)
if !ok {
return nil, 0, fmt.Errorf("unexpected object: %#v", obj)
}
if pod.Spec.Host != oldMachine || pod.Status.Host != oldMachine {
return nil, 0, fmt.Errorf("pod %v is already assigned to host %q or %q", pod.Name, pod.Spec.Host, pod.Status.Host)
}
pod.Spec.Host = machine
pod.Status.Host = machine
finalPod = pod
return pod, 0, nil
})
return finalPod, err
}
// assignPod assigns the given pod to the given machine.
func (r *BindingREST) assignPod(ctx api.Context, podID string, machine string) error {
_, err := r.setPodHostTo(ctx, podID, "", machine)
if err != nil {
return err
}
return err
}
type podLifecycle struct{}
func (h *podLifecycle) AfterUpdate(obj runtime.Object) error {
return nil
}
func (h *podLifecycle) AfterDelete(obj runtime.Object) error {
return nil
}
// StatusREST implements the REST endpoint for changing the status of a pod.
type StatusREST struct {
store *etcdgeneric.Etcd
}
func (r *StatusREST) New() runtime.Object {
return &api.Pod{}
}
// Update alters the status subset of an object.
func (r *StatusREST) Update(ctx api.Context, obj runtime.Object) (runtime.Object, bool, error) {
return r.store.Update(ctx, obj)
}