Implement GetExternalTags to return Crossplane tags for managed resource controllers to tag their external resources

Signed-off-by: Muvaffak Onus <onus.muvaffak@gmail.com>

pkg/meta/meta_test.go

@@ -810,15 +810,13 @@ func TestWasCreated(t *testing.T) {
 }
 
 func TestGetExternalName(t *testing.T) {
-	testName := "my-external-name"
-
 	cases := map[string]struct {
 		o    metav1.Object
 		want string
 	}{
 		"ExternalNameExists": {
-			o:    &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Annotations: map[string]string{ExternalNameAnnotationKey: testName}}},
-			want: testName,
+			o:    &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Annotations: map[string]string{ExternalNameAnnotationKey: name}}},
+			want: name,
 		},
 		"NoExternalName": {
 			o:    &corev1.Pod{},
@@ -830,15 +828,13 @@ func TestGetExternalName(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			got := GetExternalName(tc.o)
 			if diff := cmp.Diff(tc.want, got); diff != "" {
-				t.Errorf("WasCreated(...): -want, +got:\n%s", diff)
+				t.Errorf("GetExternalName(...): -want, +got:\n%s", diff)
 			}
 		})
 	}
 }
 
 func TestSetExternalName(t *testing.T) {
-	testName := "my-external-name"
-
 	cases := map[string]struct {
 		o    metav1.Object
 		name string
@@ -846,8 +842,8 @@ func TestSetExternalName(t *testing.T) {
 	}{
 		"SetsTheCorrectKey": {
 			o:    &corev1.Pod{},
-			name: testName,
-			want: &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Annotations: map[string]string{ExternalNameAnnotationKey: testName}}},
+			name: name,
+			want: &corev1.Pod{ObjectMeta: metav1.ObjectMeta{Annotations: map[string]string{ExternalNameAnnotationKey: name}}},
 		},
 	}
 
@@ -855,7 +851,7 @@ func TestSetExternalName(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			SetExternalName(tc.o, tc.name)
 			if diff := cmp.Diff(tc.want, tc.o); diff != "" {
-				t.Errorf("WasCreated(...): -want, +got:\n%s", diff)
+				t.Errorf("SetExternalName(...): -want, +got:\n%s", diff)
 			}
 		})
 	}

pkg/resource/fake/mocks.go

@@ -95,6 +95,15 @@ func (m *ManagedResourceReferencer) SetResourceReference(r *corev1.ObjectReferen
 // GetResourceReference gets the ResourceReference.
 func (m *ManagedResourceReferencer) GetResourceReference() *corev1.ObjectReference { return m.Ref }
 
+// ProviderReferencer is a mock that implements ProviderReferencer interface.
+type ProviderReferencer struct{ Ref *corev1.ObjectReference }
+
+// SetProviderReference sets the ProviderReference.
+func (m *ProviderReferencer) SetProviderReference(p *corev1.ObjectReference) { m.Ref = p }
+
+// GetProviderReference gets the ProviderReference.
+func (m *ProviderReferencer) GetProviderReference() *corev1.ObjectReference { return m.Ref }
+
 // LocalConnectionSecretWriterTo is a mock that implements LocalConnectionSecretWriterTo interface.
 type LocalConnectionSecretWriterTo struct {
 	Ref *v1alpha1.LocalSecretReference
@@ -200,6 +209,7 @@ type Managed struct {
 	metav1.ObjectMeta
 	ClassReferencer
 	ClaimReferencer
+	ProviderReferencer
 	ConnectionSecretWriterTo
 	Reclaimer
 	v1alpha1.ConditionedStatus

pkg/resource/interfaces.go

@@ -89,6 +89,12 @@ type CredentialsSecretReferencer interface {
 	SetCredentialsSecretReference(r v1alpha1.SecretKeySelector)
 }
 
+// A ProviderReferencer may reference a provider resource.
+type ProviderReferencer interface {
+	GetProviderReference() *corev1.ObjectReference
+	SetProviderReference(p *corev1.ObjectReference)
+}
+
 // A Claim is a Kubernetes object representing an abstract resource claim (e.g.
 // an SQL database) that may be bound to a concrete managed resource (e.g. a
 // CloudSQL instance).
@@ -122,6 +128,7 @@ type Managed interface {
 
 	ClassReferencer
 	ClaimReferencer
+	ProviderReferencer
 	ConnectionSecretWriterTo
 	Reclaimer
 

pkg/resource/resource.go

@@ -19,6 +19,7 @@ package resource
 import (
 	"context"
 	"encoding/json"
+	"strings"
 
 	"github.com/pkg/errors"
 	corev1 "k8s.io/api/core/v1"
@@ -46,6 +47,15 @@ const (
 	AnnotationDelimiter = "/"
 )
 
+// External resources are tagged/labelled with the following keys in the cloud
+// provider API if the type supports.
+const (
+	ExternalResourceTagKeyKind     = "crossplane-kind"
+	ExternalResourceTagKeyName     = "crossplane-name"
+	ExternalResourceTagKeyClass    = "crossplane-class"
+	ExternalResourceTagKeyProvider = "crossplane-provider"
+)
+
 // A ClaimKind contains the type metadata for a kind of resource claim.
 type ClaimKind schema.GroupVersionKind
 
@@ -298,3 +308,19 @@ type patch struct{ from runtime.Object }
 
 func (p *patch) Type() types.PatchType                 { return types.MergePatchType }
 func (p *patch) Data(_ runtime.Object) ([]byte, error) { return json.Marshal(p.from) }
+
+// GetExternalTags returns the identifying tags to be used to tag the external
+// resource in provider API.
+func GetExternalTags(mg Managed) map[string]string {
+	tags := map[string]string{
+		ExternalResourceTagKeyKind: strings.ToLower(mg.GetObjectKind().GroupVersionKind().GroupKind().String()),
+		ExternalResourceTagKeyName: mg.GetName(),
+	}
+	if mg.GetClassReference() != nil {
+		tags[ExternalResourceTagKeyClass] = mg.GetClassReference().Name
+	}
+	if mg.GetProviderReference() != nil {
+		tags[ExternalResourceTagKeyProvider] = mg.GetProviderReference().Name
+	}
+	return tags
+}

pkg/resource/resource_test.go

@@ -18,6 +18,7 @@ package resource
 
 import (
 	"context"
+	"strings"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
@@ -601,3 +602,36 @@ func TestApply(t *testing.T) {
 		})
 	}
 }
+
+func TestGetExternalTags(t *testing.T) {
+	provName := "prov"
+	className := "classy"
+	cases := map[string]struct {
+		o    Managed
+		want map[string]string
+	}{
+		"Successful": {
+			o: &fake.Managed{ObjectMeta: metav1.ObjectMeta{
+				Name: name,
+			},
+				ProviderReferencer: fake.ProviderReferencer{Ref: &corev1.ObjectReference{Name: provName}},
+				ClassReferencer:    fake.ClassReferencer{Ref: &corev1.ObjectReference{Name: className}},
+			},
+			want: map[string]string{
+				ExternalResourceTagKeyKind:     strings.ToLower((&fake.Managed{}).GetObjectKind().GroupVersionKind().GroupKind().String()),
+				ExternalResourceTagKeyName:     name,
+				ExternalResourceTagKeyProvider: provName,
+				ExternalResourceTagKeyClass:    className,
+			},
+		},
+	}
+
+	for name, tc := range cases {
+		t.Run(name, func(t *testing.T) {
+			got := GetExternalTags(tc.o)
+			if diff := cmp.Diff(tc.want, got); diff != "" {
+				t.Errorf("GetExternalTags(...): -want, +got:\n%s", diff)
+			}
+		})
+	}
+}