resource/aws_rds_cluster: add enable_global_write_forwarding

.changelog/14457.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+resource/aws_rds_cluster: Add `enable_global_write_forwarding` attribute
+```

aws/resource_aws_rds_cluster.go

@@ -131,6 +131,12 @@ func resourceAwsRDSCluster() *schema.Resource {
 				Optional: true,
 			},
 
+			"enable_global_write_forwarding": {
+				Type:     schema.TypeBool,
+				Optional: true,
+				Default:  false,
+			},
+
 			"reader_endpoint": {
 				Type:     schema.TypeString,
 				Computed: true,
@@ -853,6 +859,10 @@ func resourceAwsRDSClusterCreate(d *schema.ResourceData, meta interface{}) error
 			createOpts.GlobalClusterIdentifier = aws.String(attr.(string))
 		}
 
+		if attr, ok := d.GetOk("enable_global_write_forwarding"); ok {
+			createOpts.EnableGlobalWriteForwarding = aws.Bool(attr.(bool))
+		}
+
 		if attr := d.Get("vpc_security_group_ids").(*schema.Set); attr.Len() > 0 {
 			createOpts.VpcSecurityGroupIds = expandStringSet(attr)
 		}
@@ -1208,6 +1218,11 @@ func resourceAwsRDSClusterUpdate(d *schema.ResourceData, meta interface{}) error
 		requestUpdate = true
 	}
 
+	if d.HasChange("enable_global_write_forwarding") {
+		req.EnableGlobalWriteForwarding = aws.Bool(d.Get("enable_global_write_forwarding").(bool))
+		requestUpdate = true
+	}
+
 	if requestUpdate {
 		err := resource.Retry(5*time.Minute, func() *resource.RetryError {
 			_, err := conn.ModifyDBCluster(req)

aws/resource_aws_rds_cluster_test.go

@@ -1455,6 +1455,39 @@ func TestAccAWSRDSCluster_GlobalClusterIdentifier_ReplicationSourceIdentifier(t
 	})
 }
 
+// Reference: https://github.com/hashicorp/terraform-provider-aws/issues/14457
+func TestAccAWSRDSCluster_GlobalClusterIdentifier_SecondaryClustersWriteForwarding(t *testing.T) {
+	var providers []*schema.Provider
+	var primaryDbCluster, secondaryDbCluster rds.DBCluster
+
+	rNameGlobal := acctest.RandomWithPrefix("tf-acc-test-global")
+	rNamePrimary := acctest.RandomWithPrefix("tf-acc-test-primary")
+	rNameSecondary := acctest.RandomWithPrefix("tf-acc-test-secondary")
+
+	resourceNamePrimary := "aws_rds_cluster.primary"
+	resourceNameSecondary := "aws_rds_cluster.secondary"
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck: func() {
+			testAccPreCheck(t)
+			testAccMultipleRegionPreCheck(t, 2)
+			testAccPreCheckAWSRdsGlobalCluster(t)
+		},
+		ProviderFactories: testAccProviderFactoriesAlternate(&providers),
+		CheckDestroy:      testAccCheckAWSClusterDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccAWSRDSClusterConfig_GlobalClusterIdentifier_SecondaryClustersWriteForwarding(rNameGlobal, rNamePrimary, rNameSecondary),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckAWSClusterExistsWithProvider(resourceNamePrimary, &primaryDbCluster, testAccAwsRegionProviderFunc(testAccGetRegion(), &providers)),
+					testAccCheckAWSClusterExistsWithProvider(resourceNameSecondary, &secondaryDbCluster, testAccAwsRegionProviderFunc(testAccGetAlternateRegion(), &providers)),
+					resource.TestCheckResourceAttr(resourceNameSecondary, "enable_global_write_forwarding", "true"),
+				),
+			},
+		},
+	})
+}
+
 func TestAccAWSRDSCluster_Port(t *testing.T) {
 	var dbCluster1, dbCluster2 rds.DBCluster
 	rInt := acctest.RandInt()
@@ -3651,6 +3684,104 @@ resource "aws_rds_cluster_instance" "secondary" {
 `, rNameGlobal, rNamePrimary, rNameSecondary))
 }
 
+func testAccAWSRDSClusterConfig_GlobalClusterIdentifier_SecondaryClustersWriteForwarding(rNameGlobal, rNamePrimary, rNameSecondary string) string {
+	return composeConfig(
+		testAccMultipleRegionProviderConfig(2),
+		fmt.Sprintf(`
+data "aws_region" "current" {}
+
+data "aws_availability_zones" "alternate" {
+  provider = "awsalternate"
+  state    = "available"
+
+  filter {
+    name   = "opt-in-status"
+    values = ["opt-in-not-required"]
+  }
+}
+
+resource "aws_rds_global_cluster" "test" {
+  global_cluster_identifier = "%[1]s"
+  engine                    = "aurora-mysql"
+  engine_version            = "5.7.mysql_aurora.2.08.1"
+}
+
+resource "aws_rds_cluster" "primary" {
+  cluster_identifier        = "%[2]s"
+  database_name             = "mydb"
+  master_username           = "foo"
+  master_password           = "barbarbar"
+  skip_final_snapshot       = true
+  global_cluster_identifier = aws_rds_global_cluster.test.id
+  engine                    = aws_rds_global_cluster.test.engine
+  engine_version            = aws_rds_global_cluster.test.engine_version
+}
+
+resource "aws_rds_cluster_instance" "primary" {
+  identifier         = "%[2]s"
+  cluster_identifier = aws_rds_cluster.primary.id
+  instance_class     = "db.r4.large" # only db.r4 or db.r5 are valid for Aurora global db
+  engine             = aws_rds_cluster.primary.engine
+  engine_version     = aws_rds_cluster.primary.engine_version
+}
+
+resource "aws_vpc" "alternate" {
+  provider   = "awsalternate"
+  cidr_block = "10.0.0.0/16"
+
+  tags = {
+    Name = "%[3]s"
+  }
+}
+
+resource "aws_subnet" "alternate" {
+  provider          = "awsalternate"
+  count             = 3
+  vpc_id            = aws_vpc.alternate.id
+  availability_zone = data.aws_availability_zones.alternate.names[count.index]
+  cidr_block        = "10.0.${count.index}.0/24"
+
+  tags = {
+    Name = "%[3]s"
+  }
+}
+
+resource "aws_db_subnet_group" "alternate" {
+  provider   = "awsalternate"
+  name       = "%[3]s"
+  subnet_ids = aws_subnet.alternate[*].id
+}
+
+resource "aws_rds_cluster" "secondary" {
+  provider                       = "awsalternate"
+  cluster_identifier             = "%[3]s"
+  db_subnet_group_name           = aws_db_subnet_group.alternate.name
+  skip_final_snapshot            = true
+  source_region                  = data.aws_region.current.name
+  global_cluster_identifier      = aws_rds_global_cluster.test.id
+  enable_global_write_forwarding = true
+  engine                         = aws_rds_global_cluster.test.engine
+  engine_version                 = aws_rds_global_cluster.test.engine_version
+  depends_on                     = [aws_rds_cluster_instance.primary]
+
+  lifecycle {
+    ignore_changes = [
+      replication_source_identifier,
+    ]
+  }
+}
+
+resource "aws_rds_cluster_instance" "secondary" {
+  provider           = "awsalternate"
+  identifier         = "%[3]s"
+  cluster_identifier = aws_rds_cluster.secondary.id
+  instance_class     = "db.r4.large" # only db.r4 or db.r5 are valid for Aurora global db
+  engine             = aws_rds_cluster.secondary.engine
+  engine_version     = aws_rds_cluster.secondary.engine_version
+}
+`, rNameGlobal, rNamePrimary, rNameSecondary))
+}
+
 func testAccAWSRDSClusterConfig_GlobalClusterIdentifier_ReplicationSourceIdentifier(rName string) string {
 	return composeConfig(
 		testAccMultipleRegionProviderConfig(2),

tools/go.sum

@@ -420,6 +420,8 @@ github.com/hashicorp/go-cleanhttp v0.5.2/go.mod h1:kO/YDlP8L1346E6Sodw+PrpBSV4/S
 github.com/hashicorp/go-cty v1.4.1-0.20200414143053-d3edf31b6320/go.mod h1:EiZBMaudVLy8fmjf9Npq1dq9RalhveqZG5w/yz3mHWs=
 github.com/hashicorp/go-getter v1.4.0/go.mod h1:7qxyCd8rBfcShwsvxgIguu4KbS3l8bUCwg2Umn7RjeY=
 github.com/hashicorp/go-getter v1.5.0/go.mod h1:a7z7NPPfNQpJWcn4rSWFtdrSldqLdLPEF3d8nFMsSLM=
+github.com/hashicorp/go-getter v1.5.1 h1:lM9sM02nvEApQGFgkXxWbhfqtyN+AyhQmi+MaMdBDOI=
+github.com/hashicorp/go-getter v1.5.1/go.mod h1:a7z7NPPfNQpJWcn4rSWFtdrSldqLdLPEF3d8nFMsSLM=
 github.com/hashicorp/go-getter v1.5.2 h1:XDo8LiAcDisiqZdv0TKgz+HtX3WN7zA2JD1R1tjsabE=
 github.com/hashicorp/go-getter v1.5.2/go.mod h1:orNH3BTYLu/fIxGIdLjLoAJHWMDQ/UKQr5O4m3iBuoo=
 github.com/hashicorp/go-hclog v0.0.0-20180709165350-ff2cf002a8dd/go.mod h1:9bjs9uLqI8l75knNv3lV1kA55veR+WUPSiKIWcQHudI=

website/docs/r/rds_cluster.html.markdown

@@ -116,6 +116,7 @@ The following arguments are supported:
 * `engine` - (Optional) The name of the database engine to be used for this DB cluster. Defaults to `aurora`. Valid Values: `aurora`, `aurora-mysql`, `aurora-postgresql`
 * `final_snapshot_identifier` - (Optional) The name of your final DB snapshot when this DB cluster is deleted. If omitted, no final snapshot will be made.
 * `global_cluster_identifier` - (Optional) The global cluster identifier specified on [`aws_rds_global_cluster`](/docs/providers/aws/r/rds_global_cluster.html).
+* `enable_global_write_forwarding` - (Optional) Whether cluster should forward writes to an associated global cluster. Applied to secondary clusters to enable them to forward writes to an [`aws_rds_global_cluster`](/docs/providers/aws/r/rds_global_cluster.html)'s primary cluster. See the [Aurora Userguide documentation](https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/aurora-global-database-write-forwarding.html) for more information.
 * `iam_database_authentication_enabled` - (Optional) Specifies whether or mappings of AWS Identity and Access Management (IAM) accounts to database accounts is enabled. Please see [AWS Documentation](https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/UsingWithRDS.IAMDBAuth.html) for availability and limitations.
 * `iam_roles` - (Optional) A List of ARNs for the IAM roles to associate to the RDS Cluster.
 * `kms_key_id` - (Optional) The ARN for the KMS encryption key. When specifying `kms_key_id`, `storage_encrypted` needs to be set to true.