Revision Tag Support (istio-ecosystem#413)

* IstioRevisionTag implementation

I also added a bunch of integration tests. Documentation is still to
come. There are more scenarios that might need testing, we'll need to
figure that out as we go.

Signed-off-by: Daniel Grimm <[email protected]>

* Change func name to isRevisionReferenced

Signed-off-by: Daniel Grimm <[email protected]>

* Remove premature optimization

Signed-off-by: Daniel Grimm <[email protected]>

* Rename to TransientError

Signed-off-by: Daniel Grimm <[email protected]>

* Stop watching Istio resources in IstioRevision controller

Signed-off-by: Daniel Grimm <[email protected]>

---------

Signed-off-by: Daniel Grimm <[email protected]>

PROJECT

@@ -27,6 +27,14 @@ resources:
   kind: IstioRevision
   path: github.com/istio-ecosystem/sail-operator/api/v1alpha1
   version: v1alpha1
+- api:
+    crdVersion: v1
+    namespaced: false
+  controller: true
+  domain: sailoperator.io
+  kind: IstioRevisionTag
+  path: github.com/istio-ecosystem/sail-operator/api/v1alpha1
+  version: v1alpha1
 - api:
     crdVersion: v1
     namespaced: false

api/v1alpha1/istiorevisiontags_types.go

@@ -0,0 +1,204 @@
+// Copyright Istio 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 v1alpha1
+
+import (
+	"time"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+const (
+	IstioRevisionTagKind = "IstioRevisionTag"
+	DefaultRevisionTag   = "default"
+)
+
+// IstioRevisionTagSpec defines the desired state of IstioRevisionTag
+type IstioRevisionTagSpec struct {
+	// +kubebuilder:validation:Required
+	TargetRef IstioRevisionTagTargetReference `json:"targetRef"`
+}
+
+// IstioRevisionTagTargetReference can reference either Istio or IstioRevision objects in the cluster.
+type IstioRevisionTagTargetReference struct {
+	// Kind is the kind of the target resource.
+	//
+	// +kubebuilder:validation:MinLength=1
+	// +kubebuilder:validation:MaxLength=253
+	// +kubebuilder:validation:Required
+	Kind string `json:"kind"`
+
+	// Name is the name of the target resource.
+	//
+	// +kubebuilder:validation:MinLength=1
+	// +kubebuilder:validation:MaxLength=253
+	// +kubebuilder:validation:Required
+	Name string `json:"name"`
+}
+
+// IstioRevisionStatus defines the observed state of IstioRevision
+type IstioRevisionTagStatus struct {
+	// ObservedGeneration is the most recent generation observed for this
+	// IstioRevisionTag object. It corresponds to the object's generation, which is
+	// updated on mutation by the API Server. The information in the status
+	// pertains to this particular generation of the object.
+	ObservedGeneration int64 `json:"observedGeneration,omitempty"`
+
+	// Represents the latest available observations of the object's current state.
+	Conditions []IstioRevisionTagCondition `json:"conditions,omitempty"`
+
+	// Reports the current state of the object.
+	State IstioRevisionTagConditionReason `json:"state,omitempty"`
+
+	// IstiodNamespace stores the namespace of the corresponding Istiod instance
+	IstiodNamespace string `json:"istiodNamespace"`
+
+	// IstioRevision stores the name of the referenced IstioRevision
+	IstioRevision string `json:"istioRevision"`
+}
+
+// GetCondition returns the condition of the specified type
+func (s *IstioRevisionTagStatus) GetCondition(conditionType IstioRevisionTagConditionType) IstioRevisionTagCondition {
+	if s != nil {
+		for i := range s.Conditions {
+			if s.Conditions[i].Type == conditionType {
+				return s.Conditions[i]
+			}
+		}
+	}
+	return IstioRevisionTagCondition{Type: conditionType, Status: metav1.ConditionUnknown}
+}
+
+// SetCondition sets a specific condition in the list of conditions
+func (s *IstioRevisionTagStatus) SetCondition(condition IstioRevisionTagCondition) {
+	var now time.Time
+	if testTime == nil {
+		now = time.Now()
+	} else {
+		now = *testTime
+	}
+
+	// The lastTransitionTime only gets serialized out to the second.  This can
+	// break update skipping, as the time in the resource returned from the client
+	// may not match the time in our cached status during a reconcile.  We truncate
+	// here to save any problems down the line.
+	lastTransitionTime := metav1.NewTime(now.Truncate(time.Second))
+
+	for i, prevCondition := range s.Conditions {
+		if prevCondition.Type == condition.Type {
+			if prevCondition.Status != condition.Status {
+				condition.LastTransitionTime = lastTransitionTime
+			} else {
+				condition.LastTransitionTime = prevCondition.LastTransitionTime
+			}
+			s.Conditions[i] = condition
+			return
+		}
+	}
+
+	// If the condition does not exist, initialize the lastTransitionTime
+	condition.LastTransitionTime = lastTransitionTime
+	s.Conditions = append(s.Conditions, condition)
+}
+
+// IstioRevisionCondition represents a specific observation of the IstioRevision object's state.
+type IstioRevisionTagCondition struct {
+	// The type of this condition.
+	Type IstioRevisionTagConditionType `json:"type,omitempty"`
+
+	// The status of this condition. Can be True, False or Unknown.
+	Status metav1.ConditionStatus `json:"status,omitempty"`
+
+	// Unique, single-word, CamelCase reason for the condition's last transition.
+	Reason IstioRevisionTagConditionReason `json:"reason,omitempty"`
+
+	// Human-readable message indicating details about the last transition.
+	Message string `json:"message,omitempty"`
+
+	// Last time the condition transitioned from one status to another.
+	LastTransitionTime metav1.Time `json:"lastTransitionTime,omitempty"`
+}
+
+// IstioRevisionConditionType represents the type of the condition.  Condition stages are:
+// Installed, Reconciled, Ready
+type IstioRevisionTagConditionType string
+
+// IstioRevisionConditionReason represents a short message indicating how the condition came
+// to be in its present state.
+type IstioRevisionTagConditionReason string
+
+const (
+	// IstioRevisionConditionReconciled signifies whether the controller has
+	// successfully reconciled the resources defined through the CR.
+	IstioRevisionTagConditionReconciled IstioRevisionTagConditionType = "Reconciled"
+
+	// IstioRevisionTagNameAlreadyExists indicates that the a revision with the same name as the IstioRevisionTag already exists.
+	IstioRevisionTagReasonNameAlreadyExists IstioRevisionTagConditionReason = "NameAlreadyExists"
+
+	// IstioRevisionTagReasonReferenceNotFound indicates that the resource referenced by the tag's TargetRef was not found
+	IstioRevisionTagReasonReferenceNotFound IstioRevisionTagConditionReason = "RefNotFound"
+
+	// IstioRevisionReasonReconcileError indicates that the reconciliation of the resource has failed, but will be retried.
+	IstioRevisionTagReasonReconcileError IstioRevisionTagConditionReason = "ReconcileError"
+)
+
+const (
+	// IstioRevisionConditionInUse signifies whether any workload is configured to use the revision.
+	IstioRevisionTagConditionInUse IstioRevisionTagConditionType = "InUse"
+
+	// IstioRevisionReasonReferencedByWorkloads indicates that the revision is referenced by at least one pod or namespace.
+	IstioRevisionTagReasonReferencedByWorkloads IstioRevisionTagConditionReason = "ReferencedByWorkloads"
+
+	// IstioRevisionReasonNotReferenced indicates that the revision is not referenced by any pod or namespace.
+	IstioRevisionTagReasonNotReferenced IstioRevisionTagConditionReason = "NotReferencedByAnything"
+
+	// IstioRevisionReasonUsageCheckFailed indicates that the operator could not check whether any workloads use the revision.
+	IstioRevisionTagReasonUsageCheckFailed IstioRevisionTagConditionReason = "UsageCheckFailed"
+)
+
+const (
+	// IstioRevisionTagReasonHealthy indicates that the revision tag has been successfully reconciled and is in use.
+	IstioRevisionTagReasonHealthy IstioRevisionTagConditionReason = "Healthy"
+)
+
+// +kubebuilder:object:root=true
+// +kubebuilder:resource:scope=Cluster,shortName=istiorevtag,categories=istio-io
+// +kubebuilder:subresource:status
+// +kubebuilder:printcolumn:name="Status",type="string",JSONPath=".status.state",description="The current state of this object."
+// +kubebuilder:printcolumn:name="In use",type="string",JSONPath=".status.conditions[?(@.type==\"InUse\")].status",description="Whether the tag is being used by workloads."
+// +kubebuilder:printcolumn:name="Revision",type="string",JSONPath=".status.istioRevision",description="The IstioRevision this object is referencing."
+// +kubebuilder:printcolumn:name="Age",type="date",JSONPath=".metadata.creationTimestamp",description="The age of the object"
+
+// IstioRevisionTag references a Istio or IstioRevision object and serves as an alias for sidecar injection.
+type IstioRevisionTag struct {
+	metav1.TypeMeta   `json:",inline"`
+	metav1.ObjectMeta `json:"metadata,omitempty"`
+
+	Spec   IstioRevisionTagSpec   `json:"spec,omitempty"`
+	Status IstioRevisionTagStatus `json:"status,omitempty"`
+}
+
+// +kubebuilder:object:root=true
+
+// IstioRevisionList contains a list of IstioRevision
+type IstioRevisionTagList struct {
+	metav1.TypeMeta `json:",inline"`
+	metav1.ListMeta `json:"metadata,omitempty"`
+	Items           []IstioRevisionTag `json:"items"`
+}
+
+func init() {
+	SchemeBuilder.Register(&IstioRevisionTag{}, &IstioRevisionTagList{})
+}