From bfe9f00e551b004ab9afb8fefd845f83d1cb94b0 Mon Sep 17 00:00:00 2001 From: Bryan Boreham Date: Mon, 10 Sep 2018 14:58:57 +0000 Subject: [PATCH] Fake kubernetes API which implements optimistic locking Mostly copied from kubernetes/client-go files --- prog/kube-utils/kube_test.go | 30 ++ testing/kubernetes/testing/actions.go | 30 ++ testing/kubernetes/testing/fixture.go | 393 ++++++++++++++++++++++++++ 3 files changed, 453 insertions(+) create mode 100644 prog/kube-utils/kube_test.go create mode 100644 testing/kubernetes/testing/actions.go create mode 100644 testing/kubernetes/testing/fixture.go diff --git a/prog/kube-utils/kube_test.go b/prog/kube-utils/kube_test.go new file mode 100644 index 00000000..fe663e4b --- /dev/null +++ b/prog/kube-utils/kube_test.go @@ -0,0 +1,30 @@ +// Adapted from k8s.io/client-go/kubernetes/fake to use a modified ObjectTracker +package main + +import ( + "k8s.io/apimachinery/pkg/runtime" + serializer "k8s.io/apimachinery/pkg/runtime/serializer" + "k8s.io/apimachinery/pkg/watch" + "k8s.io/client-go/kubernetes/fake" + "k8s.io/client-go/testing" + + weavetracker "github.com/weaveworks/weave/testing/kubernetes/testing" +) + +var scheme = runtime.NewScheme() +var codecs = serializer.NewCodecFactory(scheme) + +func NewSimpleClientset(objects ...runtime.Object) *fake.Clientset { + o := weavetracker.NewObjectTracker(scheme, codecs.UniversalDecoder()) + for _, obj := range objects { + if err := o.Add(obj); err != nil { + panic(err) + } + } + + ret := fake.Clientset{} + ret.AddReactor("*", "*", weavetracker.ObjectReaction(o)) + ret.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil)) + + return &ret +} diff --git a/testing/kubernetes/testing/actions.go b/testing/kubernetes/testing/actions.go new file mode 100644 index 00000000..3fcf52e2 --- /dev/null +++ b/testing/kubernetes/testing/actions.go @@ -0,0 +1,30 @@ +// Modified from the original at k8s.io/client-go/testing to the bare minimum +/* +Copyright 2015 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 testing + +import ( + "k8s.io/apimachinery/pkg/runtime/schema" +) + +type Action interface { + GetNamespace() string + GetVerb() string + GetResource() schema.GroupVersionResource + GetSubresource() string + Matches(verb, resource string) bool +} diff --git a/testing/kubernetes/testing/fixture.go b/testing/kubernetes/testing/fixture.go new file mode 100644 index 00000000..60965d79 --- /dev/null +++ b/testing/kubernetes/testing/fixture.go @@ -0,0 +1,393 @@ +// Modified from the original at k8s.io/client-go/testing in line with +// https://github.com/kubernetes/kubernetes/pull/68460 +/* +Copyright 2015 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 testing + +import ( + "fmt" + "sync" + + "k8s.io/apimachinery/pkg/api/errors" + "k8s.io/apimachinery/pkg/api/meta" + metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" + "k8s.io/apimachinery/pkg/runtime" + "k8s.io/apimachinery/pkg/runtime/schema" + "k8s.io/client-go/testing" +) + +// ObjectTracker keeps track of objects. It is intended to be used to +// fake calls to a server by returning objects based on their kind, +// namespace and name. +type ObjectTracker interface { + // Add adds an object to the tracker. If object being added + // is a list, its items are added separately. + Add(obj runtime.Object) error + + // Get retrieves the object by its kind, namespace and name. + Get(gvr schema.GroupVersionResource, ns, name string) (runtime.Object, error) + + // Create adds an object to the tracker in the specified namespace. + Create(gvr schema.GroupVersionResource, obj runtime.Object, ns string) error + + // Update updates an existing object in the tracker in the specified namespace. + Update(gvr schema.GroupVersionResource, obj runtime.Object, ns string) error + + // List retrieves all objects of a given kind in the given + // namespace. Only non-List kinds are accepted. + List(gvr schema.GroupVersionResource, gvk schema.GroupVersionKind, ns string) (runtime.Object, error) + + // Delete deletes an existing object from the tracker. If object + // didn't exist in the tracker prior to deletion, Delete returns + // no error. + Delete(gvr schema.GroupVersionResource, ns, name string) error +} + +// ObjectScheme abstracts the implementation of common operations on objects. +type ObjectScheme interface { + runtime.ObjectCreater + runtime.ObjectTyper +} + +// ObjectReaction returns a ReactionFunc that applies core.Action to +// the given tracker. +func ObjectReaction(tracker ObjectTracker) testing.ReactionFunc { + return func(action testing.Action) (bool, runtime.Object, error) { + ns := action.GetNamespace() + gvr := action.GetResource() + + // Here and below we need to switch on implementation types, + // not on interfaces, as some interfaces are identical + // (e.g. UpdateAction and CreateAction), so if we use them, + // updates and creates end up matching the same case branch. + switch action := action.(type) { + + case testing.ListActionImpl: + obj, err := tracker.List(gvr, action.GetKind(), ns) + return true, obj, err + + case testing.GetActionImpl: + obj, err := tracker.Get(gvr, ns, action.GetName()) + return true, obj, err + + case testing.CreateActionImpl: + objMeta, err := meta.Accessor(action.GetObject()) + if err != nil { + return true, nil, err + } + if action.GetSubresource() == "" { + err = tracker.Create(gvr, action.GetObject(), ns) + } else { + // TODO: Currently we're handling subresource creation as an update + // on the enclosing resource. This works for some subresources but + // might not be generic enough. + err = tracker.Update(gvr, action.GetObject(), ns) + } + if err != nil { + return true, nil, err + } + obj, err := tracker.Get(gvr, ns, objMeta.GetName()) + return true, obj, err + + case testing.UpdateActionImpl: + objMeta, err := meta.Accessor(action.GetObject()) + if err != nil { + return true, nil, err + } + err = tracker.Update(gvr, action.GetObject(), ns) + if err != nil { + if errors.IsConflict(err) { // return the currently-stored version of the object + obj, _ := tracker.Get(gvr, ns, objMeta.GetName()) + return true, obj, err + } + return true, nil, err + } + obj, err := tracker.Get(gvr, ns, objMeta.GetName()) + return true, obj, err + + case testing.DeleteActionImpl: + err := tracker.Delete(gvr, ns, action.GetName()) + if err != nil { + return true, nil, err + } + return true, nil, nil + + default: + return false, nil, fmt.Errorf("no reaction implemented for %s", action) + } + } +} + +type tracker struct { + scheme ObjectScheme + decoder runtime.Decoder + lock sync.RWMutex + objects map[schema.GroupVersionResource][]runtime.Object + counter int +} + +var _ ObjectTracker = &tracker{} + +// NewObjectTracker returns an ObjectTracker that can be used to keep track +// of objects for the fake clientset. Mostly useful for unit tests. +func NewObjectTracker(scheme ObjectScheme, decoder runtime.Decoder) ObjectTracker { + return &tracker{ + scheme: scheme, + decoder: decoder, + objects: make(map[schema.GroupVersionResource][]runtime.Object), + } +} + +func (t *tracker) List(gvr schema.GroupVersionResource, gvk schema.GroupVersionKind, ns string) (runtime.Object, error) { + // Heuristic for list kind: original kind + List suffix. Might + // not always be true but this tracker has a pretty limited + // understanding of the actual API model. + listGVK := gvk + listGVK.Kind = listGVK.Kind + "List" + // GVK does have the concept of "internal version". The scheme recognizes + // the runtime.APIVersionInternal, but not the empty string. + if listGVK.Version == "" { + listGVK.Version = runtime.APIVersionInternal + } + + list, err := t.scheme.New(listGVK) + if err != nil { + return nil, err + } + + if !meta.IsListType(list) { + return nil, fmt.Errorf("%q is not a list type", listGVK.Kind) + } + + t.lock.RLock() + defer t.lock.RUnlock() + + objs, ok := t.objects[gvr] + if !ok { + return list, nil + } + + matchingObjs, err := filterByNamespaceAndName(objs, ns, "") + if err != nil { + return nil, err + } + if err := meta.SetList(list, matchingObjs); err != nil { + return nil, err + } + return list.DeepCopyObject(), nil +} + +func (t *tracker) Get(gvr schema.GroupVersionResource, ns, name string) (runtime.Object, error) { + errNotFound := errors.NewNotFound(gvr.GroupResource(), name) + + t.lock.RLock() + defer t.lock.RUnlock() + + objs, ok := t.objects[gvr] + if !ok { + return nil, errNotFound + } + + matchingObjs, err := filterByNamespaceAndName(objs, ns, name) + if err != nil { + return nil, err + } + if len(matchingObjs) == 0 { + return nil, errNotFound + } + if len(matchingObjs) > 1 { + return nil, fmt.Errorf("more than one object matched gvr %s, ns: %q name: %q", gvr, ns, name) + } + + // Only one object should match in the tracker if it works + // correctly, as Add/Update methods enforce kind/namespace/name + // uniqueness. + obj := matchingObjs[0].DeepCopyObject() + if status, ok := obj.(*metav1.Status); ok { + if status.Status != metav1.StatusSuccess { + return nil, &errors.StatusError{ErrStatus: *status} + } + } + + return obj, nil +} + +func (t *tracker) Add(obj runtime.Object) error { + if meta.IsListType(obj) { + return t.addList(obj, false) + } + objMeta, err := meta.Accessor(obj) + if err != nil { + return err + } + gvks, _, err := t.scheme.ObjectKinds(obj) + if err != nil { + return err + } + if len(gvks) == 0 { + return fmt.Errorf("no registered kinds for %v", obj) + } + for _, gvk := range gvks { + // NOTE: UnsafeGuessKindToResource is a heuristic and default match. The + // actual registration in apiserver can specify arbitrary route for a + // gvk. If a test uses such objects, it cannot preset the tracker with + // objects via Add(). Instead, it should trigger the Create() function + // of the tracker, where an arbitrary gvr can be specified. + gvr, _ := meta.UnsafeGuessKindToResource(gvk) + // Resource doesn't have the concept of "__internal" version, just set it to "". + if gvr.Version == runtime.APIVersionInternal { + gvr.Version = "" + } + + err := t.add(gvr, obj, objMeta.GetNamespace(), false) + if err != nil { + return err + } + } + return nil +} + +func (t *tracker) Create(gvr schema.GroupVersionResource, obj runtime.Object, ns string) error { + return t.add(gvr, obj, ns, false) +} + +func (t *tracker) Update(gvr schema.GroupVersionResource, obj runtime.Object, ns string) error { + return t.add(gvr, obj, ns, true) +} + +func (t *tracker) add(gvr schema.GroupVersionResource, obj runtime.Object, ns string, replaceExisting bool) error { + t.lock.Lock() + defer t.lock.Unlock() + + gr := gvr.GroupResource() + + // To avoid the object from being accidentally modified by caller + // after it's been added to the tracker, we always store the deep + // copy. + obj = obj.DeepCopyObject() + + newMeta, err := meta.Accessor(obj) + if err != nil { + return err + } + + // Propagate namespace to the new object if hasn't already been set. + if len(newMeta.GetNamespace()) == 0 { + newMeta.SetNamespace(ns) + } + + // Update version on new object + inputResourceVersion := newMeta.GetResourceVersion() + newMeta.SetResourceVersion(fmt.Sprintf("%d", t.counter)) + t.counter++ + + if ns != newMeta.GetNamespace() { + msg := fmt.Sprintf("request namespace does not match object namespace, request: %q object: %q", ns, newMeta.GetNamespace()) + return errors.NewBadRequest(msg) + } + + for i, existingObj := range t.objects[gvr] { + oldMeta, err := meta.Accessor(existingObj) + if err != nil { + return err + } + if oldMeta.GetNamespace() == newMeta.GetNamespace() && oldMeta.GetName() == newMeta.GetName() { + if replaceExisting { + if oldMeta.GetResourceVersion() != inputResourceVersion { + return errors.NewConflict(gr, newMeta.GetName(), fmt.Errorf("Resource version mismatch")) + } + t.objects[gvr][i] = obj + return nil + } + return errors.NewAlreadyExists(gr, newMeta.GetName()) + } + } + + if replaceExisting { + // Tried to update but no matching object was found. + return errors.NewNotFound(gr, newMeta.GetName()) + } + + t.objects[gvr] = append(t.objects[gvr], obj) + + return nil +} + +func (t *tracker) addList(obj runtime.Object, replaceExisting bool) error { + list, err := meta.ExtractList(obj) + if err != nil { + return err + } + errs := runtime.DecodeList(list, t.decoder) + if len(errs) > 0 { + return errs[0] + } + for _, obj := range list { + if err := t.Add(obj); err != nil { + return err + } + } + return nil +} + +func (t *tracker) Delete(gvr schema.GroupVersionResource, ns, name string) error { + t.lock.Lock() + defer t.lock.Unlock() + + found := false + + for i, existingObj := range t.objects[gvr] { + objMeta, err := meta.Accessor(existingObj) + if err != nil { + return err + } + if objMeta.GetNamespace() == ns && objMeta.GetName() == name { + t.objects[gvr] = append(t.objects[gvr][:i], t.objects[gvr][i+1:]...) + found = true + break + } + } + + if found { + return nil + } + + return errors.NewNotFound(gvr.GroupResource(), name) +} + +// filterByNamespaceAndName returns all objects in the collection that +// match provided namespace and name. Empty namespace matches +// non-namespaced objects. +func filterByNamespaceAndName(objs []runtime.Object, ns, name string) ([]runtime.Object, error) { + var res []runtime.Object + + for _, obj := range objs { + acc, err := meta.Accessor(obj) + if err != nil { + return nil, err + } + if ns != "" && acc.GetNamespace() != ns { + continue + } + if name != "" && acc.GetName() != name { + continue + } + res = append(res, obj) + } + + return res, nil +}