provider/aws: Expose zone_id from elb

builtin/providers/aws/resource_aws_elb.go

@@ -177,6 +177,11 @@ func resourceAwsElb() *schema.Resource {
 				Computed: true,
 			},
 
+			"zone_id": &schema.Schema{
+				Type:     schema.TypeString,
+				Computed: true,
+			},
+
 			"tags": tagsSchema(),
 		},
 	}
@@ -281,6 +286,7 @@ func resourceAwsElbRead(d *schema.ResourceData, meta interface{}) error {
 
 	d.Set("name", *lb.LoadBalancerName)
 	d.Set("dns_name", *lb.DNSName)
+	d.Set("zone_id", *lb.CanonicalHostedZoneNameID)
 	d.Set("internal", *lb.Scheme == "internal")
 	d.Set("availability_zones", lb.AvailabilityZones)
 	d.Set("instances", flattenInstances(lb.Instances))

website/source/docs/providers/aws/r/elb.html.markdown

@@ -96,3 +96,4 @@ The following attributes are exported:
 * `source_security_group` - The name of the security group that you can use as
   part of your inbound rules for your load balancer's back-end application
   instances.
+* `zone_id` - The canonical hosted zone ID of the ELB (to be used in a Route 53 Alias record)