Add overrides implementation to keep legacy instanceType along with i…

…nstanceTypeRef

config/crds/resources/apiextensions.k8s.io_v1_customresourcedefinition_alloydbinstances.alloydb.cnrm.cloud.google.com.yaml

@@ -57,6 +57,11 @@ spec:
           metadata:
             type: object
           spec:
+            oneOf:
+            - required:
+              - instanceType
+            - required:
+              - instanceTypeRef
             properties:
               annotations:
                 additionalProperties:
@@ -120,6 +125,11 @@ spec:
                   instance, an error will be thrown. If this is absent for a ZONAL
                   instance, instance is created in a random zone with available capacity.
                 type: string
+              instanceType:
+                description: DEPRECATED. Although this field is still available, there
+                  is limited support. We recommend that you use `spec.instanceTypeRef`
+                  instead.
+                type: string
               instanceTypeRef:
                 oneOf:
                 - not:
@@ -171,7 +181,6 @@ spec:
                 type: string
             required:
             - clusterRef
-            - instanceTypeRef
             type: object
           status:
             properties:

pkg/resourceoverrides/alloydb_instance.go

@@ -0,0 +1,64 @@
+// Copyright 2024 Google LLC
+//
+// 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 resourceoverrides
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/GoogleCloudPlatform/k8s-config-connector/pkg/k8s"
+
+	"github.com/hashicorp/terraform-plugin-sdk/v2/terraform"
+	apiextensions "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+)
+
+var (
+	instanceTypeField    = []string{"instanceType"}
+	instanceTypeRefField = []string{"instanceTypeRef"}
+)
+
+func GetAlloyDBInstanceResourceOverrides() ResourceOverrides {
+	ro := ResourceOverrides{
+		Kind: "AlloyDBInstance",
+	}
+	// Preserve the legacy non-reference field 'instanceType' after it is changed to
+	// a reference field, 'instanceTypeRef'.
+	ro.Overrides = append(ro.Overrides, keepInstanceTypeField())
+	return ro
+}
+
+func keepInstanceTypeField() ResourceOverride {
+	o := ResourceOverride{}
+	o.CRDDecorate = func(crd *apiextensions.CustomResourceDefinition) error {
+		return PreserveMutuallyExclusiveNonReferenceField(crd, nil, instanceTypeRefField[0], instanceTypeField[0])
+	}
+	o.PreActuationTransform = func(r *k8s.Resource) error {
+		if err := FavorAuthoritativeFieldOverLegacyField(r, instanceTypeField, instanceTypeRefField); err != nil {
+			return fmt.Errorf("error handling '%v' and '%v' fields in pre-actuation transformation: %w", strings.Join(instanceTypeField, "."), strings.Join(instanceTypeRefField, "."), err)
+		}
+		return nil
+	}
+	o.PostActuationTransform = func(original, reconciled *k8s.Resource, tfState *terraform.InstanceState, dclState *unstructured.Unstructured) error {
+		if err := PreserveUserSpecifiedLegacyField(original, reconciled, instanceTypeField...); err != nil {
+			return fmt.Errorf("error preserving '%v' in post-actuation transformation: %w", strings.Join(instanceTypeField, "."), err)
+		}
+		if err := PruneDefaultedAuthoritativeFieldIfOnlyLegacyFieldSpecified(original, reconciled, instanceTypeField, instanceTypeRefField); err != nil {
+			return fmt.Errorf("error conditionally pruning '%v' in post-actuation transformation: %w", strings.Join(instanceTypeRefField, "."), err)
+		}
+		return nil
+	}
+	return o
+}

pkg/resourceoverrides/overrides.go

@@ -232,6 +232,7 @@ func init() {
 	Handler.Register(GetVPCAccessConnectorResourceOverrides())
 	Handler.Register(GetRedisInstanceResourceOverrides())
 	Handler.Register(GetRunServiceResourceOverrides())
+	Handler.Register(GetAlloyDBInstanceResourceOverrides())
 
 	// IAM
 	Handler.Register(GetIAMCustomRoleResourceOverrides())