Added public_dns and private_dns to aws_eip

aws/data_source_aws_eip.go

@@ -3,6 +3,7 @@ package aws
 import (
 	"fmt"
 	"log"
+	"strings"
 
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/service/ec2"
@@ -44,11 +45,19 @@ func dataSourceAwsEip() *schema.Resource {
 				Type:     schema.TypeString,
 				Computed: true,
 			},
+			"private_dns": {
+				Type:     schema.TypeString,
+				Computed: true,
+			},
 			"public_ip": {
 				Type:     schema.TypeString,
 				Optional: true,
 				Computed: true,
 			},
+			"public_dns": {
+				Type:     schema.TypeString,
+				Computed: true,
+			},
 			"public_ipv4_pool": {
 				Type:     schema.TypeString,
 				Computed: true,
@@ -86,7 +95,6 @@ func dataSourceAwsEipRead(d *schema.ResourceData, meta interface{}) error {
 		req.Filters = nil
 	}
 
-	log.Printf("[DEBUG] Reading EIP: %s", req)
 	resp, err := conn.DescribeAddresses(req)
 	if err != nil {
 		return fmt.Errorf("error describing EC2 Address: %s", err)
@@ -112,8 +120,30 @@ func dataSourceAwsEipRead(d *schema.ResourceData, meta interface{}) error {
 	d.Set("instance_id", eip.InstanceId)
 	d.Set("network_interface_id", eip.NetworkInterfaceId)
 	d.Set("network_interface_owner_id", eip.NetworkInterfaceOwnerId)
+
+	region := *conn.Config.Region
+
 	d.Set("private_ip", eip.PrivateIpAddress)
+	if eip.PrivateIpAddress != nil {
+		dashIP := strings.Replace(*eip.PrivateIpAddress, ".", "-", -1)
+
+		if region == "us-east-1" {
+			d.Set("private_dns", fmt.Sprintf("ip-%s.ec2.internal", dashIP))
+		} else {
+			d.Set("private_dns", fmt.Sprintf("ip-%s.%s.compute.internal", dashIP, region))
+		}
+	}
+
 	d.Set("public_ip", eip.PublicIp)
+	if eip.PublicIp != nil {
+		dashIP := strings.Replace(*eip.PublicIp, ".", "-", -1)
+
+		if region == "us-east-1" {
+			d.Set("public_dns", fmt.Sprintf("ec2-%s.compute-1.amazonaws.com", dashIP))
+		} else {
+			d.Set("public_dns", fmt.Sprintf("ec2-%s.%s.compute.amazonaws.com", dashIP, region))
+		}
+	}
 	d.Set("public_ipv4_pool", eip.PublicIpv4Pool)
 	d.Set("tags", tagsToMap(eip.Tags))
 

aws/resource_aws_eip.go

@@ -70,11 +70,23 @@ func resourceAwsEip() *schema.Resource {
 				Computed: true,
 			},
 
+			"public_dns": {
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+			},
+
 			"private_ip": {
 				Type:     schema.TypeString,
 				Computed: true,
 			},
 
+			"private_dns": {
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+			},
+
 			"associate_with_private_ip": {
 				Type:     schema.TypeString,
 				Optional: true,
@@ -220,8 +232,28 @@ func resourceAwsEipRead(d *schema.ResourceData, meta interface{}) error {
 	} else {
 		d.Set("network_interface", "")
 	}
+
+	region := *ec2conn.Config.Region
 	d.Set("private_ip", address.PrivateIpAddress)
+	if address.PrivateIpAddress != nil {
+		dashIP := strings.Replace(*address.PrivateIpAddress, ".", "-", -1)
+
+		if region == "us-east-1" {
+			d.Set("private_dns", fmt.Sprintf("ip-%s.ec2.internal", dashIP))
+		} else {
+			d.Set("private_dns", fmt.Sprintf("ip-%s.%s.compute.internal", dashIP, region))
+		}
+	}
 	d.Set("public_ip", address.PublicIp)
+	if address.PublicIp != nil {
+		dashIP := strings.Replace(*address.PublicIp, ".", "-", -1)
+
+		if region == "us-east-1" {
+			d.Set("public_dns", fmt.Sprintf("ec2-%s.compute-1.amazonaws.com", dashIP))
+		} else {
+			d.Set("public_dns", fmt.Sprintf("ec2-%s.%s.compute.amazonaws.com", dashIP, region))
+		}
+	}
 	d.Set("public_ipv4_pool", address.PublicIpv4Pool)
 
 	// On import (domain never set, which it must've been if we created),

website/docs/d/eip.html.markdown

@@ -71,6 +71,10 @@ In addition to all arguments above, the following attributes are exported:
 * `network_interface_id` - The ID of the network interface.
 * `network_interface_owner_id` - The ID of the AWS account that owns the network interface.
 * `private_ip` - The private IP address associated with the Elastic IP address.
+* `private_dns` - The Private DNS associated with the Elastic IP address.
 * `public_ip` - Public IP address of Elastic IP.
+* `public_dns` - Public DNS associated with the Elastic IP address.
 * `public_ipv4_pool` - The ID of an address pool.
 * `tags` - Key-value map of tags associated with Elastic IP.
+
+~> **Note:** The data source computes the `public_dns` and `private_dns` attributes according to the [VPC DNS Guide](https://docs.aws.amazon.com/vpc/latest/userguide/vpc-dns.html#vpc-dns-hostnames) as they are not available with the EC2 API.

website/docs/r/eip.html.markdown

@@ -117,13 +117,17 @@ In addition to all arguments above, the following attributes are exported:
 
 * `id` - Contains the EIP allocation ID.
 * `private_ip` - Contains the private IP address (if in VPC).
+* `private_dns` - The Private DNS associated with the Elastic IP address (if in VPC).
 * `associate_with_private_ip` - Contains the user specified private IP address
 (if in VPC).
 * `public_ip` - Contains the public IP address.
+* `public_dns` - Public DNS associated with the Elastic IP address.
 * `instance` - Contains the ID of the attached instance.
 * `network_interface` - Contains the ID of the attached network interface.
 * `public_ipv4_pool` - EC2 IPv4 address pool identifier (if in VPC).
 
+~> **Note:** The resource computes the `public_dns` and `private_dns` attributes according to the [VPC DNS Guide](https://docs.aws.amazon.com/vpc/latest/userguide/vpc-dns.html#vpc-dns-hostnames) as they are not available with the EC2 API.
+
 ## Timeouts
 `aws_eip` provides the following [Timeouts](/docs/configuration/resources.html#timeouts) configuration options: