Fix aws_rds_reserved_instance_offering data source

.changelog/40281.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+data-source/aws_rds_reserved_instance_offering: When `product_description` (e.g., "postgresql") is a substring of multiple products, fix `Error: multiple RDS Reserved Instance Offerings matched; use additional constraints to reduce matches to a single RDS Reserved Instance Offering`
+```

internal/service/rds/reserved_instance_offering_data_source.go

@@ -81,8 +81,12 @@ func dataSourceReservedOfferingRead(ctx context.Context, d *schema.ResourceData,
 		ProductDescription: aws.String(d.Get("product_description").(string)),
 	}
 
-	offering, err := findReservedDBInstancesOffering(ctx, conn, input, tfslices.PredicateTrue[*types.ReservedDBInstancesOffering]())
-
+	// A filter is necessary because the API returns all products where the product description contains
+	// the input product description. Sending "mysql" will return "mysql" *and* "aurora-mysql" offerings,
+	// causing an error: multiple RDS Reserved Instance Offerings matched
+	offering, err := findReservedDBInstancesOffering(ctx, conn, input, func(v *types.ReservedDBInstancesOffering) bool {
+		return aws.ToString(v.ProductDescription) == d.Get("product_description").(string) && aws.ToString(v.DBInstanceClass) == d.Get("db_instance_class").(string)
+	})
 	if err != nil {
 		return sdkdiag.AppendFromErr(diags, tfresource.SingularDataSourceFindError("RDS Reserved Instance Offering", err))
 	}
@@ -103,7 +107,6 @@ func dataSourceReservedOfferingRead(ctx context.Context, d *schema.ResourceData,
 
 func findReservedDBInstancesOffering(ctx context.Context, conn *rds.Client, input *rds.DescribeReservedDBInstancesOfferingsInput, filter tfslices.Predicate[*types.ReservedDBInstancesOffering]) (*types.ReservedDBInstancesOffering, error) {
 	output, err := findReservedDBInstancesOfferings(ctx, conn, input, filter)
-
 	if err != nil {
 		return nil, err
 	}

internal/service/rds/reserved_instance_offering_data_source_test.go

@@ -4,14 +4,58 @@
 package rds_test
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/hashicorp/terraform-plugin-testing/helper/resource"
 	"github.com/hashicorp/terraform-provider-aws/internal/acctest"
 	"github.com/hashicorp/terraform-provider-aws/names"
 )
 
-func TestAccRDSInstanceOffering_basic(t *testing.T) {
+const (
+	testInstanceClass = "db.r5.large"
+)
+
+func TestAccRDSReservedInstanceOffering_basic(t *testing.T) {
+	ctx := acctest.Context(t)
+	dataSourceName := "data.aws_rds_reserved_instance_offering.test"
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck:                 func() { acctest.PreCheck(ctx, t) },
+		ProtoV5ProviderFactories: acctest.ProtoV5ProviderFactories,
+		ErrorCheck:               acctest.ErrorCheck(t, names.RDSServiceID),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccReservedInstanceOfferingConfig_basic(testInstanceClass, "postgresql"),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttrSet(dataSourceName, "currency_code"),
+					resource.TestCheckResourceAttr(dataSourceName, "db_instance_class", testInstanceClass),
+					resource.TestCheckResourceAttr(dataSourceName, names.AttrDuration, "31536000"),
+					resource.TestCheckResourceAttrSet(dataSourceName, "fixed_price"),
+					resource.TestCheckResourceAttr(dataSourceName, "multi_az", acctest.CtFalse),
+					resource.TestCheckResourceAttrSet(dataSourceName, "offering_id"),
+					resource.TestCheckResourceAttr(dataSourceName, "offering_type", "All Upfront"),
+					resource.TestCheckResourceAttr(dataSourceName, "product_description", "postgresql"),
+				),
+			},
+			{
+				Config: testAccReservedInstanceOfferingConfig_basic(testInstanceClass, "aurora-postgresql"),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttrSet(dataSourceName, "currency_code"),
+					resource.TestCheckResourceAttr(dataSourceName, "db_instance_class", testInstanceClass),
+					resource.TestCheckResourceAttr(dataSourceName, names.AttrDuration, "31536000"),
+					resource.TestCheckResourceAttrSet(dataSourceName, "fixed_price"),
+					resource.TestCheckResourceAttr(dataSourceName, "multi_az", acctest.CtFalse),
+					resource.TestCheckResourceAttrSet(dataSourceName, "offering_id"),
+					resource.TestCheckResourceAttr(dataSourceName, "offering_type", "All Upfront"),
+					resource.TestCheckResourceAttr(dataSourceName, "product_description", "aurora-postgresql"),
+				),
+			},
+		},
+	})
+}
+
+func TestAccRDSReservedInstanceOffering_mysql(t *testing.T) {
 	ctx := acctest.Context(t)
 	dataSourceName := "data.aws_rds_reserved_instance_offering.test"
 
@@ -21,10 +65,10 @@ func TestAccRDSInstanceOffering_basic(t *testing.T) {
 		ErrorCheck:               acctest.ErrorCheck(t, names.RDSServiceID),
 		Steps: []resource.TestStep{
 			{
-				Config: testAccInstanceOfferingConfig_basic(),
+				Config: testAccReservedInstanceOfferingConfig_basic(testInstanceClass, "mysql"),
 				Check: resource.ComposeTestCheckFunc(
 					resource.TestCheckResourceAttrSet(dataSourceName, "currency_code"),
-					resource.TestCheckResourceAttr(dataSourceName, "db_instance_class", "db.t2.micro"),
+					resource.TestCheckResourceAttr(dataSourceName, "db_instance_class", testInstanceClass),
 					resource.TestCheckResourceAttr(dataSourceName, names.AttrDuration, "31536000"),
 					resource.TestCheckResourceAttrSet(dataSourceName, "fixed_price"),
 					resource.TestCheckResourceAttr(dataSourceName, "multi_az", acctest.CtFalse),
@@ -33,18 +77,31 @@ func TestAccRDSInstanceOffering_basic(t *testing.T) {
 					resource.TestCheckResourceAttr(dataSourceName, "product_description", "mysql"),
 				),
 			},
+			{
+				Config: testAccReservedInstanceOfferingConfig_basic(testInstanceClass, "aurora-mysql"),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttrSet(dataSourceName, "currency_code"),
+					resource.TestCheckResourceAttr(dataSourceName, "db_instance_class", testInstanceClass),
+					resource.TestCheckResourceAttr(dataSourceName, names.AttrDuration, "31536000"),
+					resource.TestCheckResourceAttrSet(dataSourceName, "fixed_price"),
+					resource.TestCheckResourceAttr(dataSourceName, "multi_az", acctest.CtFalse),
+					resource.TestCheckResourceAttrSet(dataSourceName, "offering_id"),
+					resource.TestCheckResourceAttr(dataSourceName, "offering_type", "All Upfront"),
+					resource.TestCheckResourceAttr(dataSourceName, "product_description", "aurora-mysql"),
+				),
+			},
 		},
 	})
 }
 
-func testAccInstanceOfferingConfig_basic() string {
-	return `
+func testAccReservedInstanceOfferingConfig_basic(class, desc string) string {
+	return fmt.Sprintf(`
 data "aws_rds_reserved_instance_offering" "test" {
-  db_instance_class   = "db.t2.micro"
+  db_instance_class   = %[1]q
   duration            = 31536000
   multi_az            = false
   offering_type       = "All Upfront"
-  product_description = "mysql"
+  product_description = %[2]q
 }
-`
+`, class, desc)
 }