r/aws_vpc_dhcp_options_association: Support default DHCP Options ID

.changelog/22722.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+resource/aws_vpc_dhcp_options_association: Support `default` DHCP Options ID
+```

internal/service/ec2/vpc_dhcp_options_association.go

@@ -154,9 +154,17 @@ func VPCDHCPOptionsAssociationCreateResourceID(dhcpOptionsID, vpcID string) stri
 func VPCDHCPOptionsAssociationParseResourceID(id string) (string, string, error) {
 	parts := strings.Split(id, vpcDHCPOptionsAssociationResourceIDSeparator)
 
-	// DHCP Options ID and VPC ID themselves contain '-'.
-	if len(parts) == 4 && parts[0] != "" && parts[1] != "" && parts[2] != "" && parts[3] != "" {
-		return strings.Join([]string{parts[0], parts[1]}, vpcDHCPOptionsAssociationResourceIDSeparator), strings.Join([]string{parts[2], parts[3]}, vpcDHCPOptionsAssociationResourceIDSeparator), nil
+	// The DHCP Options ID either contains '-' or is the special value "default".
+	// The VPC ID contains '-'.
+	switch n := len(parts); n {
+	case 3:
+		if parts[0] == DefaultDHCPOptionsID && parts[1] != "" && parts[2] != "" {
+			return parts[0], strings.Join([]string{parts[1], parts[2]}, vpcDHCPOptionsAssociationResourceIDSeparator), nil
+		}
+	case 4:
+		if parts[0] != "" && parts[1] != "" && parts[2] != "" && parts[3] != "" {
+			return strings.Join([]string{parts[0], parts[1]}, vpcDHCPOptionsAssociationResourceIDSeparator), strings.Join([]string{parts[2], parts[3]}, vpcDHCPOptionsAssociationResourceIDSeparator), nil
+		}
 	}
 
 	return "", "", fmt.Errorf("unexpected format for ID (%[1]s), expected DHCPOptionsID%[2]sVPCID", id, vpcDHCPOptionsAssociationResourceIDSeparator)

internal/service/ec2/vpc_dhcp_options_association_test.go

@@ -106,6 +106,32 @@ func TestAccEC2VPCDHCPOptionsAssociation_disappears(t *testing.T) {
 	})
 }
 
+func TestAccEC2VPCDHCPOptionsAssociation_default(t *testing.T) {
+	resourceName := "aws_vpc_dhcp_options_association.test"
+	rName := sdkacctest.RandomWithPrefix(acctest.ResourcePrefix)
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck:     func() { acctest.PreCheck(t) },
+		ErrorCheck:   acctest.ErrorCheck(t, ec2.EndpointsID),
+		Providers:    acctest.Providers,
+		CheckDestroy: testAccCheckVPCDHCPOptionsAssociationDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccVPCDHCPOptionsAssociationDefaultConfig(rName),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckVPCDHCPOptionsAssociationExist(resourceName),
+				),
+			},
+			{
+				ResourceName:      resourceName,
+				ImportStateIdFunc: testAccVPCDHCPOptionsAssociationVPCImportIdFunc(resourceName),
+				ImportState:       true,
+				ImportStateVerify: true,
+			},
+		},
+	})
+}
+
 func testAccVPCDHCPOptionsAssociationVPCImportIdFunc(resourceName string) resource.ImportStateIdFunc {
 	return func(s *terraform.State) (string, error) {
 		rs, ok := s.RootModule().Resources[resourceName]
@@ -204,3 +230,20 @@ resource "aws_vpc_dhcp_options_association" "test" {
 }
 `, rName)
 }
+
+func testAccVPCDHCPOptionsAssociationDefaultConfig(rName string) string {
+	return fmt.Sprintf(`
+resource "aws_vpc" "test" {
+  cidr_block = "10.1.0.0/16"
+
+  tags = {
+    Name = %[1]q
+  }
+}
+
+resource "aws_vpc_dhcp_options_association" "test" {
+  vpc_id          = aws_vpc.test.id
+  dhcp_options_id = "default"
+}
+`, rName)
+}