Merge pull request #9525 from maxenglander/datasource-aws-db-subnet-g…

…roup

data-source/aws_db_subnet_group: create aws_db_subnet_group data-source

aws/data_source_aws_db_subnet_group.go

@@ -0,0 +1,88 @@
+package aws
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/service/rds"
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
+)
+
+func dataSourceAwsDbSubnetGroup() *schema.Resource {
+	return &schema.Resource{
+		Read: dataSourceAwsDbSubnetGroupRead,
+
+		Schema: map[string]*schema.Schema{
+			"arn": {
+				Type:     schema.TypeString,
+				Computed: true,
+			},
+			"description": {
+				Type:     schema.TypeString,
+				Computed: true,
+			},
+			"name": {
+				Type:     schema.TypeString,
+				Required: true,
+			},
+			"status": {
+				Type:     schema.TypeString,
+				Computed: true,
+			},
+			"subnet_ids": {
+				Type:     schema.TypeSet,
+				Computed: true,
+				Elem:     &schema.Schema{Type: schema.TypeString},
+			},
+			"vpc_id": {
+				Type:     schema.TypeString,
+				Computed: true,
+			},
+		},
+	}
+}
+
+func dataSourceAwsDbSubnetGroupRead(d *schema.ResourceData, meta interface{}) error {
+	conn := meta.(*AWSClient).rdsconn
+
+	name := d.Get("name").(string)
+
+	opts := &rds.DescribeDBSubnetGroupsInput{
+		DBSubnetGroupName: aws.String(name),
+	}
+
+	log.Printf("[DEBUG] Reading DB SubnetGroup: %s", name)
+
+	resp, err := conn.DescribeDBSubnetGroups(opts)
+	if err != nil {
+		return fmt.Errorf("error reading DB SubnetGroup (%s): %w", name, err)
+	}
+
+	if resp == nil || resp.DBSubnetGroups == nil {
+		return fmt.Errorf("error reading DB SubnetGroup (%s): empty response", name)
+	}
+	if len(resp.DBSubnetGroups) > 1 {
+		return fmt.Errorf("Your query returned more than one result. Please try a more specific search criteria.")
+	}
+
+	dbSubnetGroup := resp.DBSubnetGroups[0]
+
+	d.SetId(aws.StringValue(dbSubnetGroup.DBSubnetGroupName))
+	d.Set("arn", dbSubnetGroup.DBSubnetGroupArn)
+	d.Set("description", dbSubnetGroup.DBSubnetGroupDescription)
+	d.Set("name", dbSubnetGroup.DBSubnetGroupName)
+	d.Set("status", dbSubnetGroup.SubnetGroupStatus)
+
+	subnets := make([]string, 0, len(dbSubnetGroup.Subnets))
+	for _, v := range dbSubnetGroup.Subnets {
+		subnets = append(subnets, aws.StringValue(v.SubnetIdentifier))
+	}
+	if err := d.Set("subnet_ids", subnets); err != nil {
+		return fmt.Errorf("error setting subnet_ids: %w", err)
+	}
+
+	d.Set("vpc_id", dbSubnetGroup.VpcId)
+
+	return nil
+}

aws/data_source_aws_db_subnet_group_test.go

@@ -0,0 +1,83 @@
+package aws
+
+import (
+	"fmt"
+	"regexp"
+	"testing"
+
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/acctest"
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/resource"
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
+)
+
+func TestAccAWSDbSubnetGroupDataSource_basic(t *testing.T) {
+	var providers []*schema.Provider
+	rName := acctest.RandomWithPrefix("tf-acc-test")
+	resourceName := "aws_db_subnet_group.test"
+	dataSourceName := "data.aws_db_subnet_group.test"
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck:          func() { testAccPreCheck(t) },
+		ProviderFactories: testAccProviderFactories(&providers),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccAWSDBSubnetGroupDataSourceConfig(rName),
+				Check: resource.ComposeAggregateTestCheckFunc(
+					resource.TestCheckResourceAttrPair(resourceName, "arn", dataSourceName, "arn"),
+					resource.TestCheckResourceAttrPair(resourceName, "description", dataSourceName, "description"),
+					resource.TestCheckResourceAttrPair(resourceName, "name", dataSourceName, "name"),
+					resource.TestCheckResourceAttrPair(resourceName, "subnet_ids", dataSourceName, "subnet_ids"),
+					resource.TestCheckResourceAttrSet(dataSourceName, "status"),
+					resource.TestCheckResourceAttrSet(dataSourceName, "vpc_id"),
+				),
+			},
+		},
+	})
+}
+
+func TestAccAWSDbSubnetGroupDataSource_nonexistent(t *testing.T) {
+	var providers []*schema.Provider
+
+	resource.ParallelTest(t, resource.TestCase{
+		PreCheck:          func() { testAccPreCheck(t) },
+		ProviderFactories: testAccProviderFactories(&providers),
+		Steps: []resource.TestStep{
+			{
+				Config:      testAccAWSDBSubnetGroupDataSourceConfig_NonExistent,
+				ExpectError: regexp.MustCompile(`error reading DB SubnetGroup \(tf-acc-test-does-not-exist\)`),
+			},
+		},
+	})
+}
+
+const testAccAWSDBSubnetGroupDataSourceConfig_NonExistent = `
+data "aws_db_subnet_group" "test" {
+  name = "tf-acc-test-does-not-exist"
+}
+`
+
+func testAccAWSDBSubnetGroupDataSourceConfig(rName string) string {
+	return composeConfig(
+		testAccAvailableAZsNoOptInConfig(),
+		fmt.Sprintf(`
+resource "aws_vpc" "test" {
+  cidr_block = "10.0.0.0/16"
+}
+
+resource "aws_subnet" "test" {
+  count             = 2
+  availability_zone = data.aws_availability_zones.available.names[count.index]
+  cidr_block        = "10.0.${count.index}.0/24"
+  vpc_id            = aws_vpc.test.id
+}
+
+resource "aws_db_subnet_group" "test" {
+  name       = "%s"
+  subnet_ids = aws_subnet.test.*.id
+}
+
+data "aws_db_subnet_group" "test" {
+  name = aws_db_subnet_group.test.name
+}
+`, rName))
+}

aws/provider.go

@@ -200,6 +200,7 @@ func Provider() *schema.Provider {
 			"aws_db_event_categories":                        dataSourceAwsDbEventCategories(),
 			"aws_db_instance":                                dataSourceAwsDbInstance(),
 			"aws_db_snapshot":                                dataSourceAwsDbSnapshot(),
+			"aws_db_subnet_group":                            dataSourceAwsDbSubnetGroup(),
 			"aws_directory_service_directory":                dataSourceAwsDirectoryServiceDirectory(),
 			"aws_dx_gateway":                                 dataSourceAwsDxGateway(),
 			"aws_dynamodb_table":                             dataSourceAwsDynamoDbTable(),

website/docs/d/db_subnet_group.html.markdown

@@ -0,0 +1,35 @@
+---
+subcategory: "RDS"
+layout: "aws"
+page_title: "AWS: aws_db_subnet_group"
+description: |-
+  Get information on an RDS Database Subnet Group.
+---
+
+# Data Source: aws_db_subnet_group
+
+Use this data source to get information about an RDS subnet group.
+
+## Example Usage
+
+```hcl
+data "aws_db_subnet_group" "database" {
+  name = "my-test-database-subnet-group"
+}
+```
+
+## Argument Reference
+
+The following arguments are supported:
+
+* `name` - (Required) The name of the RDS database subnet group.
+
+## Attributes Reference
+
+In addition to all arguments above, the following attributes are exported:
+
+* `arn` - The Amazon Resource Name (ARN) for the DB subnet group.
+* `description` - Provides the description of the DB subnet group.
+* `status` - Provides the status of the DB subnet group.
+* `subnet_ids` - Contains a list of subnet identifiers.
+* `vpc_id` - Provides the VPC ID of the subnet group.