Add NatGateway data source

aws/data_source_aws_nat_gateway.go

@@ -0,0 +1,114 @@
+package aws
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/service/ec2"
+	"github.com/hashicorp/terraform/helper/schema"
+)
+
+func dataSourceAwsNatGateway() *schema.Resource {
+	return &schema.Resource{
+		Read: dataSourceAwsNatGatewayRead,
+
+		Schema: map[string]*schema.Schema{
+			"id": {
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+			},
+			"state": {
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+			},
+			"vpc_id": {
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+			},
+			"subnet_id": {
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+			},
+			"filter": ec2CustomFiltersSchema(),
+		},
+	}
+}
+
+func dataSourceAwsNatGatewayRead(d *schema.ResourceData, meta interface{}) error {
+	conn := meta.(*AWSClient).ec2conn
+
+	log.Printf("[DEBUG] Reading NAT Gateways.")
+
+	req := &ec2.DescribeNatGatewaysInput{}
+
+	if id, ok := d.GetOk("id"); ok {
+		req.NatGatewayIds = aws.StringSlice([]string{id.(string)})
+	}
+
+	if vpc_id, ok := d.GetOk("vpc_id"); ok {
+		req.Filter = append(req.Filter, buildEC2AttributeFilterList(
+			map[string]string{
+				"vpc-id": vpc_id.(string),
+			},
+		)...)
+	}
+
+	if state, ok := d.GetOk("state"); ok {
+		req.Filter = append(req.Filter, buildEC2AttributeFilterList(
+			map[string]string{
+				"state": state.(string),
+			},
+		)...)
+	}
+
+	if subnet_id, ok := d.GetOk("subnet_id"); ok {
+		req.Filter = append(req.Filter, buildEC2AttributeFilterList(
+			map[string]string{
+				"subnet-id": subnet_id.(string),
+			},
+		)...)
+	}
+
+	req.Filter = append(req.Filter, buildEC2CustomFilterList(
+		d.Get("filter").(*schema.Set),
+	)...)
+	if len(req.Filter) == 0 {
+		// Don't send an empty filters list; the EC2 API won't accept it.
+		req.Filter = nil
+	}
+
+	resp, err := conn.DescribeNatGateways(req)
+	if err != nil {
+		return err
+	}
+	if resp == nil || len(resp.NatGateways) == 0 {
+		return fmt.Errorf("no matching NAT gateway found: %#v", req)
+	}
+	if len(resp.NatGateways) > 1 {
+		return fmt.Errorf("multiple NAT gateways matched; use additional constraints to reduce matches to a single NAT gateway")
+	}
+
+	ngw := resp.NatGateways[0]
+
+	d.SetId(aws.StringValue(ngw.NatGatewayId))
+	d.Set("state", ngw.State)
+	d.Set("subnet_id", ngw.SubnetId)
+	d.Set("vpc_id", ngw.VpcId)
+
+	for _, address := range ngw.NatGatewayAddresses {
+		if *address.AllocationId != "" {
+			d.Set("allocated_eip_id", address.AllocationId)
+			d.Set("allocated_eni_id", address.NetworkInterfaceId)
+			d.Set("allocated_private_ip", address.PrivateIp)
+			d.Set("allocated_public_ip", address.PublicIp)
+			break
+		}
+	}
+
+	return nil
+}

aws/data_source_aws_nat_gateway_test.go

@@ -0,0 +1,89 @@
+package aws
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/hashicorp/terraform/helper/acctest"
+	"github.com/hashicorp/terraform/helper/resource"
+)
+
+func TestAccDataSourceAwsNatGateway(t *testing.T) {
+	// This is used as a portion of CIDR network addresses.
+	rInt := acctest.RandIntRange(4, 254)
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: testAccDataSourceAwsNatGatewayConfig(rInt),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttrPair(
+						"data.aws_nat_gateway.test_by_id", "id",
+						"aws_nat_gateway.test", "id"),
+					resource.TestCheckResourceAttrPair(
+						"data.aws_nat_gateway.test_by_subnet_id", "subnet_id",
+						"aws_nat_gateway.test", "subnet_id"),
+					resource.TestCheckResourceAttrSet("data.aws_nat_gateway.test_by_id", "state"),
+					resource.TestCheckNoResourceAttr("data.aws_nat_gateway.test_by_id", "attached_vpc_id"),
+				),
+			},
+		},
+	})
+}
+
+func testAccDataSourceAwsNatGatewayConfig(rInt int) string {
+	return fmt.Sprintf(`
+provider "aws" {
+  region = "us-west-2"
+}
+
+resource "aws_vpc" "test" {
+  cidr_block = "172.%d.0.0/16"
+  tags {
+    Name = "terraform-testacc-nat-gateway-data-source-%d"
+  }
+}
+
+resource "aws_subnet" "test" {
+  vpc_id            = "${aws_vpc.test.id}"
+  cidr_block        = "172.%d.123.0/24"
+  availability_zone = "us-west-2a"
+
+  tags {
+    Name = "terraform-testacc-nat-gateway-data-source-%d"
+  }
+}
+
+# EIPs are not taggable
+resource "aws_eip" "test" {
+  vpc = true
+}
+
+# IGWs are required for an NGW to spin up; manual dependency
+resource "aws_internet_gateway" "test" {
+  vpc_id = "${aws_vpc.test.id}"
+  tags {
+    Name = "terraform-testacc-nat-gateway-data-source-%d"
+  }
+}
+
+# NGWs are not taggable, either
+resource "aws_nat_gateway" "test" {
+  subnet_id     = "${aws_subnet.test.id}"
+  allocation_id = "${aws_eip.test.id}"
+
+  depends_on = ["aws_internet_gateway.test"]
+}
+
+data "aws_nat_gateway" "test_by_id" {
+  id = "${aws_nat_gateway.test.id}"
+}
+
+data "aws_nat_gateway" "test_by_subnet_id" {
+  subnet_id = "${aws_nat_gateway.test.subnet_id}"
+}
+
+`, rInt, rInt, rInt, rInt, rInt)
+}

aws/provider.go

@@ -201,6 +201,7 @@ func Provider() terraform.ResourceProvider {
 			"aws_kms_alias":                        dataSourceAwsKmsAlias(),
 			"aws_kms_ciphertext":                   dataSourceAwsKmsCiphetext(),
 			"aws_kms_secret":                       dataSourceAwsKmsSecret(),
+			"aws_nat_gateway":                      dataSourceAwsNatGateway(),
 			"aws_partition":                        dataSourceAwsPartition(),
 			"aws_prefix_list":                      dataSourceAwsPrefixList(),
 			"aws_redshift_service_account":         dataSourceAwsRedshiftServiceAccount(),

website/aws.erb

@@ -140,6 +140,9 @@
                         <li<%= sidebar_current("docs-aws-datasource-kms-secret") %>>
                             <a href="/docs/providers/aws/d/kms_secret.html">aws_kms_secret</a>
                         </li>
+                        <li<%= sidebar_current("docs-aws-datasource-nat-gateway") %>>
+ +                          <a href="/docs/providers/aws/d/nat_gateway.html">aws_nat_gateway</a>
+ +                        </li>
                         <li<%= sidebar_current("docs-aws-datasource-partition") %>>
                             <a href="/docs/providers/aws/d/partition.html">aws_partition</a>
                         </li>

website/docs/d/nat_gateway.html.markdown

@@ -0,0 +1,61 @@
+---
+layout: "aws"
+page_title: "AWS: aws_nat_gateway"
+sidebar_current: "docs-aws-datasource-nat_gateway"
+description: |-
+    Provides details about a specific Nat Gateway
+---
+
+# aws\_nat\_gateway
+
+`aws_nat_gateway` provides details about a specific Nat Gateway.
+
+## Example Usage
+
+```hcl
+variable "subnet_id" {}
+
+data "aws_nat_gateway" "default" {
+
+  subnet_id = "${var.subnet_id}"
+
+}
+```
+
+## Argument Reference
+
+The arguments of this data source act as filters for querying the available
+Nat Gateway in the current region. The given filters must match exactly one
+Nat Gateway whose data will be exported as attributes.
+
+* `nat_gateway_id` - (Optional) The id of the specific Nat Gateway to retrieve.
+
+* `subnet_id` - (Optional) The id of subnet that the Nat Gateway resides in.
+
+* `vpc_id` - (Optional) The id of the VPC that the Nat Gateway resides in.
+
+* `filter` - (Optional) Custom filter block as described below.
+
+More complex filters can be expressed using one or more `filter` sub-blocks,
+which take the following arguments:
+
+* `name` - (Required) The name of the field to filter by, as defined by
+  [the underlying AWS API](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DescribeNatGateways.html).
+
+* `values` - (Required) Set of values that are accepted for the given field.
+  An Nat Gateway will be selected if any one of the given values matches.
+
+## Attributes Reference
+
+All of the argument attributes except `filter` block are also exported as
+result attributes. This data source will complete the data by populating
+any fields that are not included in the configuration with the data for
+the selected Nat Gateway.
+
+`addresses` are also exported with the following attributes, when they are relevant:
+Each attachement supports the following:
+
+* `allocated_eip_id` - The Id of the EIP allocated to the selected Nat Gateway.
+* `allocated_eni_id` - The Id of the ENI allocated to the selected Nat Gateway.
+* `allocated_private_ip` - The private Ip address of the selected Nat Gateway.
+* `allocated_public_ip` - The public Ip (EIP) address of the selected Nat Gateway.