Repository: crossplane-contrib/provider-aws (go)

Issue:
RDSInstance can't get into Sync=True state with an warning  'api error InvalidParameterCombination: No modifications were requested'
### What happened?

RDSInstance MR can't get into `SYNC=True` state
This issue might be related to: #1795


### How can we reproduce it?
I have below RDS Instance MR
```
apiVersion: database.aws.crossplane.io/v1beta1
kind: RDSInstance
metadata:
  annotations:
    crossplane.io/composition-resource-name: rds
    crossplane.io/external-name: us1-ekswac001-rdswac001    
  creationTimestamp: "2023-03-23T14:43:16Z"
  finalizers:
  - finalizer.managedresource.crossplane.io
  generateName: wac-ekswac001-rdswac001-
  generation: 129675
  labels:
    crossplane.io/claim-name: ekswac001-rdswac001
    crossplane.io/claim-namespace: wac
    crossplane.io/composite: ekswac001-rdswac001-4tshm
  name: wac-ekswac001-rdswac001-h58tx
  ownerReferences:
  - apiVersion: rds.aws.crossplane.sinch.com/v1alpha1
    blockOwnerDeletion: true
    controller: true
    kind: XMySQLInstance
    name: ekswac001-rdswac001-4tshm
    uid: a8211232-ea1e-429e-b477-ebfbecc20058
  resourceVersion: "446399353"
  uid: 05a94c62-ddaf-4ee7-b885-a3704f782091
spec:
  deletionPolicy: Orphan
  forProvider:
    allocatedStorage: 333
    applyModificationsImmediately: false
    autoMinorVersionUpgrade: true
    availabilityZone: us-east-1a
    backupRetentionPeriod: 1
    caCertificateIdentifier: rds-ca-2019
    copyTagsToSnapshot: true
    dbInstanceClass: db.r5.4xlarge
    dbName: db
    dbParameterGroupName: rdswac001-db-parameter-group
    dbSubnetGroupName: private_subnets_vpc-xxx
    deletionProtection: false
    enableCloudwatchLogsExports:
    - audit
    enableIAMDatabaseAuthentication: false
    enablePerformanceInsights: true
    engine: mysql
    engineVersion: 5.7.38
    kmsKeyId: 6a1a9e12-xxx-xxx-xxx-xxx
    licenseModel: general-public-license
    masterPasswordSecretRef:
      key: password
      name: ekswac001-rdswac001-master-password
      namespace: wac
    masterUsername: root
    maxAllocatedStorage: 1000
    monitoringInterval: 60
    monitoringRoleArn: arn:aws:iam::xxx:role/rds-monitoring-role
    multiAZ: true
    optionGroupName: sinch-default-mysql-5-7
    performanceInsightsKMSKeyId: arn:aws:kms:us-east-1:xxx:key/6a1a9e12-xxx-xxx-xxx-xxx
    performanceInsightsRetentionPeriod: 7
    port: 3306
    preferredBackupWindow: 14:00-16:00
    preferredMaintenanceWindow: mon:02:30-mon:03:00
    publiclyAccessible: false
    region: us-east-1
    skipFinalSnapshotBeforeDeletion: true
    storageEncrypted: true
    storageType: gp2
    tags:
    - key: crossplane-kind
      value: rdsinstance.database.aws.crossplane.io
    - key: crossplane-name
      value: wac-ekswac001-rdswac001-h58tx
    - key: crossplane-providerconfig
      value: crossplane-provider-aws
    vpcSecurityGroupIds:
    - sg-0fxxx
    - sg-09xxx
  providerConfigRef:
    name: crossplane-provider-aws
  publishConnectionDetailsTo:
    configRef:
      name: default
    metadata:
      labels:
        secret.crossplane.io/owner-uid: 05a94c62-ddaf-4ee7-b885-a3704f782091
    name: wac-ekswac001-rdswac001-rdsinstance
status:
  atProvider:
    allocatedStorage: 333
    backupRetentionPeriod: 1
    dbInstanceArn: arn:aws:rds:us-east-1:xxx:db:us1-ekswac001-rdswac001
    dbInstanceStatus: available
    dbParameterGroups:
    - dbParameterGroupName: rdswac001-db-parameter-group
      parameterApplyStatus: in-sync
    dbResourceId: db-xxx
    dbSubnetGroup:
      dbSubnetGroupDescription: This is a private subnet group for AWS RDS instances.
        Only containing our regular private subnets in vpc-xxx
      dbSubnetGroupName: private_subnets_vpc-xxx
      subnetGroupStatus: Complete
      subnets:
      - subnetAvailabilityZone:
          name: us-east-1c
        subnetIdentifier: subnet-5xxx
        subnetStatus: Active
      - subnetAvailabilityZone:
          name: us-east-1b
        subnetIdentifier: subnet-0xxx
        subnetStatus: Active
      - subnetAvailabilityZone:
          name: us-east-1a
        subnetIdentifier: subnet-exxx
        subnetStatus: Active
      vpcId: vpc-xxx
    endpoint:
      address: us1-ekswac001-rdswac001.xxx.us-east-1.rds.amazonaws.com
      hostedZoneId: Z2R2ITUGPM61AM
      port: 3306
    enhancedMonitoringResourceArn: arn:aws:logs:us-east-1:xxx:log-group:RDSOSMetrics:log-stream:db-xxx
    instanceCreateTime: "2022-08-04T06:34:53Z"
    latestRestorableTime: "2023-08-30T11:00:00Z"
    optionGroupMemberships:
    - optionGroupName: sinch-default-mysql-5-7
      status: in-sync
    pendingModifiedValues:
      pendingCloudwatchLogsExports: {}
    performanceInsightsEnabled: true
    secondaryAvailabilityZone: us-east-1c
    vpcSecurityGroups:
    - status: active
      vpcSecurityGroupId: sg-0fxxx
    - status: active
      vpcSecurityGroupId: sg-09xxx
  conditions:
  - lastTransitionTime: "2023-07-18T04:28:07Z"
    message: 'update failed: cannot modify RDS instance: api error InvalidParameterCombination:
      No modifications were requested'
    reason: ReconcileError
    status: "False"
    type: Synced
  - lastTransitionTime: "2023-06-02T06:06:53Z"
    reason: Available
    status: "True"
    type: Ready
```

I get an event `cannot modify RDS instance: api error InvalidParameterCombination: No modifications were requested`:
```
kubectl describe rdsinstances.database.aws.crossplane.io wac-ekswac001-rdswac001-h58tx
Events:
  Type     Reason                        Age                    From                                            Message
  ----     ------                        ----                   ----                                            -------
  Warning  CannotUpdateExternalResource  79s (x9917 over 3d1h)  managed/rdsinstance.database.aws.crossplane.io  cannot modify RDS instance: api error InvalidParameterCombination: No modifications were requested
```

In AWS CloudTrail I can see:
```
    "errorCode": "InvalidParameterCombinationException",
    "errorMessage": "No modifications were requested",
    "requestParameters": {
        "allowMajorVersionUpgrade": false,
        "dBInstanceIdentifier": "us1-ekswac001-rdswac001",
        "applyImmediately": false
    },
```

Provider Logs
```
kubectl logs -n crossplane-system pod/crossplane-provider-aws-447dacb385f5-d6f4645df-6rqfx

{"level":"info","ts":"2023-09-04T09:53:00.064Z","logger":"provider-aws","msg":"Alpha feature enabled","flag":"EnableAlphaExternalSecretStores"}
Setup endpointgroup
W0904 09:53:00.918953       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 09:53:00.920521       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
[controller-runtime] log.SetLogger(...) was never called, logs will not be displayed:
goroutine 3936 [running]:
runtime/debug.Stack()
        runtime/debug/stack.go:24 +0x65
sigs.k8s.io/controller-runtime/pkg/log.eventuallyFulfillRoot()
        sigs.k8s.io/controller-runtime@v0.15.0/pkg/log/log.go:59 +0xbd
sigs.k8s.io/controller-runtime/pkg/log.(*delegatingLogSink).WithValues(0xc0008d2080, {0xc0065effa0, 0x2, 0x2})
        sigs.k8s.io/controller-runtime@v0.15.0/pkg/log/deleg.go:168 +0x54
github.com/go-logr/logr.Logger.WithValues(...)
        github.com/go-logr/logr@v1.2.4/logr.go:323
sigs.k8s.io/controller-runtime/pkg/builder.(*Builder).doController.func1(0xc0065eff80)
        sigs.k8s.io/controller-runtime@v0.15.0/pkg/builder/controller.go:398 +0x182
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler(0xc0005fbf40, {0x749d9a0, 0xc0004b9700}, {0x625de60?, 0xc0065eff60?})
        sigs.k8s.io/controller-runtime@v0.15.0/pkg/internal/controller/controller.go:305 +0x1b9
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem(0xc0005fbf40, {0x749d9a0, 0xc0004b9700})
        sigs.k8s.io/controller-runtime@v0.15.0/pkg/internal/controller/controller.go:265 +0x1d9
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2.2()
        sigs.k8s.io/controller-runtime@v0.15.0/pkg/internal/controller/controller.go:226 +0x85
created by sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2
        sigs.k8s.io/controller-runtime@v0.15.0/pkg/internal/controller/controller.go:222 +0x333
W0904 10:02:47.922518       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:07:48.924422       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:12:54.926296       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:19:22.928934       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:26:00.932433       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:32:34.934234       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:38:29.935659       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:45:13.940025       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:52:38.941015       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 10:59:48.944220       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 11:09:45.946386       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 11:16:10.949184       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 11:26:01.952099       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 11:32:02.953704       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 11:41:57.955356       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 11:47:20.957188       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 11:53:46.958749       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 12:01:47.962187       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 12:09:17.964217       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 12:16:02.967047       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 12:22:45.968958       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 12:27:48.970744       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 12:34:03.973531       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 12:41:08.975225       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
W0904 12:48:53.978472       1 warnings.go:70] BucketPolicy has been deprecated. Use spec.forProvider.policy in Bucket instead.
```

### What environment did it happen in?
Crossplane version: `1.13.2`
provider-aws: `0.43.0`


Pull request description:
fix(database): Ignore AvailabilityZone if MultiAZ is set
### Description of your changes

Only pass `spec.forProvider.availabilityZone` during update calls if `spec.forProvider.multiAZ` is false.

Fixes #1870

I have:

- [x] Read and followed Crossplane's [contribution process].
- [x] Run `make reviewable test` to ensure this PR is ready for review.

### How has this code been tested

Unit tests

[contribution process]: https://git.io/fj2m9


Patch:
diff --git a/apis/database/v1beta1/rdsinstance_types.go b/apis/database/v1beta1/rdsinstance_types.go
index ed5bfa660..059d8c124 100644
--- a/apis/database/v1beta1/rdsinstance_types.go
+++ b/apis/database/v1beta1/rdsinstance_types.go
@@ -276,8 +276,9 @@ type RDSInstanceParameters struct {
 	// Default: A random, system-chosen Availability Zone in the endpoint's AWS
 	// Region.
 	// Example: us-east-1d
-	// Constraint: The AvailabilityZone parameter can't be specified if the MultiAZ
-	// parameter is set to true. The specified Availability Zone must be in the
+	// Constraint: The AvailabilityZone parameter is ignored if the MultiAZ
+	// is set to true.
+	// The specified Availability Zone must be in the
 	// same AWS Region as the current endpoint.
 	// +immutable
 	// +optional
diff --git a/package/crds/database.aws.crossplane.io_rdsinstances.yaml b/package/crds/database.aws.crossplane.io_rdsinstances.yaml
index 3f898d826..13779ab62 100644
--- a/package/crds/database.aws.crossplane.io_rdsinstances.yaml
+++ b/package/crds/database.aws.crossplane.io_rdsinstances.yaml
@@ -146,9 +146,9 @@ spec:
                       and Availability Zones, see Regions and Availability Zones (http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Concepts.RegionsAndAvailabilityZones.html).
                       Default: A random, system-chosen Availability Zone in the endpoint''s
                       AWS Region. Example: us-east-1d Constraint: The AvailabilityZone
-                      parameter can''t be specified if the MultiAZ parameter is set
-                      to true. The specified Availability Zone must be in the same
-                      AWS Region as the current endpoint.'
+                      parameter is ignored if the MultiAZ is set to true. The specified
+                      Availability Zone must be in the same AWS Region as the current
+                      endpoint.'
                     type: string
                   backupRetentionPeriod:
                     description: 'BackupRetentionPeriod is the number of days for
diff --git a/pkg/clients/database/rds.go b/pkg/clients/database/rds.go
index a9266cbe7..9acd883a2 100644
--- a/pkg/clients/database/rds.go
+++ b/pkg/clients/database/rds.go
@@ -318,7 +318,8 @@ func GenerateRestoreRDSInstanceToPointInTimeInput(name string, p *v1beta1.RDSIns
 // CreatePatch creates a *v1beta1.RDSInstanceParameters that has only the changed
 // values between the target *v1beta1.RDSInstanceParameters and the current
 // *rds.DBInstance
-func CreatePatch(in *rdstypes.DBInstance, target *v1beta1.RDSInstanceParameters) (*v1beta1.RDSInstanceParameters, error) {
+func CreatePatch(in *rdstypes.DBInstance, spec *v1beta1.RDSInstanceParameters) (*v1beta1.RDSInstanceParameters, error) { //nolint:gocyclo
+	target := spec.DeepCopy()
 	currentParams := &v1beta1.RDSInstanceParameters{}
 	LateInitialize(currentParams, in)
 
@@ -329,6 +330,15 @@ func CreatePatch(in *rdstypes.DBInstance, target *v1beta1.RDSInstanceParameters)
 		})
 	}
 
+	// AvailabilityZone parameters is not allowed for MultiAZ deployments.
+	// So set this to nil if that is the case to avoid unnecessary diffs.
+	if ptr.Deref(target.MultiAZ, false) {
+		target.AvailabilityZone = nil
+	}
+	if ptr.Deref(currentParams.MultiAZ, false) {
+		currentParams.AvailabilityZone = nil
+	}
+
 	// Don't attempt to scale down storage if autoscaling is enabled,
 	// and the current storage is larger than what was once
 	// requested. We still want to allow the user to manually scale


Test patch:
diff --git a/pkg/clients/database/rds_test.go b/pkg/clients/database/rds_test.go
index 693c43b97..20b3a2945 100644
--- a/pkg/clients/database/rds_test.go
+++ b/pkg/clients/database/rds_test.go
@@ -128,16 +128,19 @@ func TestCreatePatch(t *testing.T) {
 					AllocatedStorage: allocatedStorage,
 					CharacterSetName: &characterSetName,
 					DBName:           &dbName,
+					AvailabilityZone: ptr.To("az1"),
 				},
 				p: &v1beta1.RDSInstanceParameters{
 					AllocatedStorage: awsclient.IntAddress(awsclient.Int64(30)),
 					CharacterSetName: &characterSetName,
 					DBName:           &dbName,
+					AvailabilityZone: ptr.To("az2"),
 				},
 			},
 			want: want{
 				patch: &v1beta1.RDSInstanceParameters{
 					AllocatedStorage: awsclient.IntAddress(awsclient.Int64(30)),
+					AvailabilityZone: ptr.To("az2"),
 				},
 			},
 		},
@@ -210,6 +213,21 @@ func TestCreatePatch(t *testing.T) {
 				patch: &v1beta1.RDSInstanceParameters{},
 			},
 		},
+		"IgnoreDifferentAvailabilityZoneForMultiAZ": {
+			args: args{
+				db: &rdstypes.DBInstance{
+					AvailabilityZone: ptr.To("az1"),
+					MultiAZ:          true,
+				},
+				p: &v1beta1.RDSInstanceParameters{
+					AvailabilityZone: ptr.To("az2"),
+					MultiAZ:          ptr.To(true),
+				},
+			},
+			want: want{
+				patch: &v1beta1.RDSInstanceParameters{},
+			},
+		},
 	}
 
 	for name, tc := range cases {
@@ -473,6 +491,23 @@ func TestIsUpToDate(t *testing.T) {
 			},
 			want: true,
 		},
+		"NoUpdateForDifferentAvailabilityZoneWhenMultiAZ": {
+			args: args{
+				db: rdstypes.DBInstance{
+					AvailabilityZone: ptr.To("az1"),
+					MultiAZ:          true,
+				},
+				r: v1beta1.RDSInstance{
+					Spec: v1beta1.RDSInstanceSpec{
+						ForProvider: v1beta1.RDSInstanceParameters{
+							AvailabilityZone: ptr.To("az2"),
+							MultiAZ:          ptr.To(true),
+						},
+					},
+				},
+			},
+			want: true,
+		},
 	}
 
 	for name, tc := range cases {