Adding a computed ARN for the S3 Bucket as per #3666

builtin/providers/aws/resource_aws_s3_bucket.go

@@ -28,6 +28,12 @@ func resourceAwsS3Bucket() *schema.Resource {
 				ForceNew: true,
 			},
 
+			"arn": &schema.Schema{
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+			},
+
 			"acl": &schema.Schema{
 				Type:     schema.TypeString,
 				Default:  "private",
@@ -376,6 +382,8 @@ func resourceAwsS3BucketRead(d *schema.ResourceData, meta interface{}) error {
 		return err
 	}
 
+	d.Set("arn", fmt.Sprint("arn:aws:s3:::", d.Id()))
+
 	return nil
 }
 

builtin/providers/aws/resource_aws_s3_bucket_test.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"math/rand"
 	"reflect"
+	"regexp"
 	"strconv"
 	"testing"
 	"time"
@@ -17,6 +18,10 @@ import (
 )
 
 func TestAccAWSS3Bucket_basic(t *testing.T) {
+
+	arnRegexp := regexp.MustCompile(
+		"^arn:aws:s3:::")
+
 	resource.Test(t, resource.TestCase{
 		PreCheck:     func() { testAccPreCheck(t) },
 		Providers:    testAccProviders,
@@ -32,6 +37,8 @@ func TestAccAWSS3Bucket_basic(t *testing.T) {
 						"aws_s3_bucket.bucket", "region", "us-west-2"),
 					resource.TestCheckResourceAttr(
 						"aws_s3_bucket.bucket", "website_endpoint", ""),
+					resource.TestMatchResourceAttr(
+						"aws_s3_bucket.bucket", "arn", arnRegexp),
 				),
 			},
 		},

website/source/docs/providers/aws/r/s3_bucket.html.markdown

@@ -107,6 +107,7 @@ The versioning supports the following:
 The following attributes are exported:
 
 * `id` - The name of the bucket.
+* `arn` - The ARN of the bucket. Will be of format `arn:aws:s3:::bucketname`
 * `hosted_zone_id` - The [Route 53 Hosted Zone ID](http://docs.aws.amazon.com/general/latest/gr/rande.html#s3_website_region_endpoints) for this bucket's region.
 * `region` - The AWS region this bucket resides in.
 * `website_endpoint` - The website endpoint, if the bucket is configured with a website. If not, this will be an empty string.