strategy.go

/*
Copyright 2017 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 instance

// this was copied from where else and edited to fit our objects

import (
	api "github.com/kubernetes-incubator/service-catalog/pkg/api"
	apiequality "k8s.io/apimachinery/pkg/api/equality"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/util/validation/field"
	genericapirequest "k8s.io/apiserver/pkg/endpoints/request"
	"k8s.io/apiserver/pkg/registry/rest"
	"k8s.io/apiserver/pkg/storage/names"
	utilfeature "k8s.io/apiserver/pkg/util/feature"

	"github.com/golang/glog"
	sc "github.com/kubernetes-incubator/service-catalog/pkg/apis/servicecatalog"
	scv "github.com/kubernetes-incubator/service-catalog/pkg/apis/servicecatalog/validation"
	scfeatures "github.com/kubernetes-incubator/service-catalog/pkg/features"
)

// NewScopeStrategy returns a new NamespaceScopedStrategy for instances
func NewScopeStrategy() rest.NamespaceScopedStrategy {
	return instanceRESTStrategies
}

// implements interfaces RESTCreateStrategy, RESTUpdateStrategy, RESTDeleteStrategy,
// NamespaceScopedStrategy, and RESTGracefulDeleteStrategy.
// The implementation disallows any modifications to the instance.Status fields.
type instanceRESTStrategy struct {
	runtime.ObjectTyper // inherit ObjectKinds method
	names.NameGenerator // GenerateName method for CreateStrategy
}

// implements interface RESTUpdateStrategy. This implementation validates updates to
// instance.Status updates only and disallows any modifications to the instance.Spec.
type instanceStatusRESTStrategy struct {
	instanceRESTStrategy
}

// implements interface RESTUpdateStrategy. This implementation validates updates to
// instance.Spec.ClusterServicePlanRef and instance.Spec.ClusterServiceClassRef only and disallows
// any modifications to the remaining instance.Spec or Status fields.
type instanceReferenceRESTStrategy struct {
	instanceRESTStrategy
}

var (
	instanceRESTStrategies = instanceRESTStrategy{
		// embeds to pull in existing code behavior from upstream

		ObjectTyper: api.Scheme,
		// use the generator from upstream k8s, or implement method
		// `GenerateName(base string) string`
		NameGenerator: names.SimpleNameGenerator,
	}
	_ rest.RESTCreateStrategy         = instanceRESTStrategies
	_ rest.RESTUpdateStrategy         = instanceRESTStrategies
	_ rest.RESTDeleteStrategy         = instanceRESTStrategies
	_ rest.RESTGracefulDeleteStrategy = instanceRESTStrategies

	instanceStatusUpdateStrategy = instanceStatusRESTStrategy{
		instanceRESTStrategies,
	}
	_ rest.RESTUpdateStrategy = instanceStatusUpdateStrategy

	instanceReferenceUpdateStrategy = instanceReferenceRESTStrategy{
		instanceRESTStrategies,
	}
	_ rest.RESTUpdateStrategy = instanceReferenceUpdateStrategy
)

// Canonicalize does not transform a instance.
func (instanceRESTStrategy) Canonicalize(obj runtime.Object) {
	_, ok := obj.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to create")
	}
}

// NamespaceScoped returns false as instances are not scoped to a namespace.
func (instanceRESTStrategy) NamespaceScoped() bool {
	return true
}

// PrepareForCreate receives a the incoming ServiceInstance and clears it's
// Status and Service[Class|Plan]Ref fields. These are not user settable fields.
func (instanceRESTStrategy) PrepareForCreate(ctx genericapirequest.Context, obj runtime.Object) {
	instance, ok := obj.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to create")
	}

	if utilfeature.DefaultFeatureGate.Enabled(scfeatures.OriginatingIdentity) {
		setServiceInstanceUserInfo(instance, ctx)
	}

	// Creating a brand new object, thus it must have no
	// status. We can't fail here if they passed a status in, so
	// we just wipe it clean.
	instance.Status = sc.ServiceInstanceStatus{}

	instance.Spec.ClusterServiceClassRef = nil
	instance.Spec.ClusterServicePlanRef = nil
	// Fill in the first entry set to "creating"?
	instance.Status.Conditions = []sc.ServiceInstanceCondition{}
	instance.Finalizers = []string{sc.FinalizerServiceCatalog}
	instance.Generation = 1
}

func (instanceRESTStrategy) Validate(ctx genericapirequest.Context, obj runtime.Object) field.ErrorList {
	return scv.ValidateServiceInstance(obj.(*sc.ServiceInstance))
}

func (instanceRESTStrategy) AllowCreateOnUpdate() bool {
	return false
}

func (instanceRESTStrategy) AllowUnconditionalUpdate() bool {
	return false
}

func (instanceRESTStrategy) PrepareForUpdate(ctx genericapirequest.Context, new, old runtime.Object) {
	newServiceInstance, ok := new.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to update to")
	}
	oldServiceInstance, ok := old.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to update from")
	}

	// Do not allow any updates to the Status field while updating the Spec
	newServiceInstance.Status = oldServiceInstance.Status

	// Do not allow updates to Service[Class|Plan]Ref fields
	newServiceInstance.Spec.ClusterServiceClassRef = oldServiceInstance.Spec.ClusterServiceClassRef
	newServiceInstance.Spec.ClusterServicePlanRef = oldServiceInstance.Spec.ClusterServicePlanRef

	// Clear out the ClusterServicePlanRef so that it is resolved during reconciliation
	if newServiceInstance.Spec.ClusterServicePlanExternalName != oldServiceInstance.Spec.ClusterServicePlanExternalName {
		newServiceInstance.Spec.ClusterServicePlanRef = nil
	}

	// Spec updates bump the generation so that we can distinguish between
	// spec changes and other changes to the object.
	if !apiequality.Semantic.DeepEqual(oldServiceInstance.Spec, newServiceInstance.Spec) {
		if utilfeature.DefaultFeatureGate.Enabled(scfeatures.OriginatingIdentity) {
			setServiceInstanceUserInfo(newServiceInstance, ctx)
		}
		newServiceInstance.Generation = oldServiceInstance.Generation + 1
	}
}

func (instanceRESTStrategy) ValidateUpdate(ctx genericapirequest.Context, new, old runtime.Object) field.ErrorList {
	newServiceInstance, ok := new.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to validate to")
	}
	oldServiceInstance, ok := old.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to validate from")
	}

	return scv.ValidateServiceInstanceUpdate(newServiceInstance, oldServiceInstance)
}

// CheckGracefulDelete sets the UserInfo on the resource to that of the user that
// initiated the delete.
// Note that this is a hack way of setting the UserInfo. However, there is not
// currently any other mechanism in the Delete strategies for getting access to
// the resource being deleted and the context.
func (instanceRESTStrategy) CheckGracefulDelete(ctx genericapirequest.Context, obj runtime.Object, options *metav1.DeleteOptions) bool {
	if utilfeature.DefaultFeatureGate.Enabled(scfeatures.OriginatingIdentity) {
		serviceInstance, ok := obj.(*sc.ServiceInstance)
		if !ok {
			glog.Fatal("received a non-instance object to delete")
		}
		setServiceInstanceUserInfo(serviceInstance, ctx)
	}
	// Don't actually do graceful deletion. We are just using this strategy to set the user info prior to reconciling the delete.
	return false
}

func (instanceStatusRESTStrategy) PrepareForUpdate(ctx genericapirequest.Context, new, old runtime.Object) {
	newServiceInstance, ok := new.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to update to")
	}
	oldServiceInstance, ok := old.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to update from")
	}
	// Status changes are not allowed to update spec
	newServiceInstance.Spec = oldServiceInstance.Spec
}

func (instanceStatusRESTStrategy) ValidateUpdate(ctx genericapirequest.Context, new, old runtime.Object) field.ErrorList {
	newServiceInstance, ok := new.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to validate to")
	}
	oldServiceInstance, ok := old.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to validate from")
	}

	return scv.ValidateServiceInstanceStatusUpdate(newServiceInstance, oldServiceInstance)
}

func (instanceReferenceRESTStrategy) PrepareForUpdate(ctx genericapirequest.Context, new, old runtime.Object) {
	newServiceInstance, ok := new.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to update to")
	}
	oldServiceInstance, ok := old.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to update from")
	}
	// Reference changes are not allowed to update spec, so stash the new
	// ones away and overwrite with all the old ones and then update them
	// again.
	newClusterServiceClassRef := newServiceInstance.Spec.ClusterServiceClassRef
	newClusterServicePlanRef := newServiceInstance.Spec.ClusterServicePlanRef
	newServiceInstance.Spec = oldServiceInstance.Spec
	newServiceInstance.Spec.ClusterServiceClassRef = newClusterServiceClassRef
	newServiceInstance.Spec.ClusterServicePlanRef = newClusterServicePlanRef
	newServiceInstance.Status = oldServiceInstance.Status
}

func (instanceReferenceRESTStrategy) ValidateUpdate(ctx genericapirequest.Context, new, old runtime.Object) field.ErrorList {
	newServiceInstance, ok := new.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to validate to")
	}
	oldServiceInstance, ok := old.(*sc.ServiceInstance)
	if !ok {
		glog.Fatal("received a non-instance object to validate from")
	}

	return scv.ValidateServiceInstanceReferencesUpdate(newServiceInstance, oldServiceInstance)
}

// setServiceInstanceUserInfo injects user.Info from the request context
func setServiceInstanceUserInfo(instance *sc.ServiceInstance, ctx genericapirequest.Context) {
	instance.Spec.UserInfo = nil
	if user, ok := genericapirequest.UserFrom(ctx); ok {
		instance.Spec.UserInfo = &sc.UserInfo{
			Username: user.GetName(),
			UID:      user.GetUID(),
			Groups:   user.GetGroups(),
		}
		if extra := user.GetExtra(); len(extra) > 0 {
			instance.Spec.UserInfo.Extra = map[string]sc.ExtraValue{}
			for k, v := range extra {
				instance.Spec.UserInfo.Extra[k] = sc.ExtraValue(v)
			}
		}
	}
}