resource/aws_s3_bucket: Convert region to read-only attribute

Reference: #592
Reference: #1656

Output from acceptance testing (NOTE: CUR data source and resource need to be tested in standalone account due to Organization permissions and appear to be failing due to new validation in the API that's not handled in the resource yet):

```
--- PASS: TestAccAWSS3Bucket_acceleration (65.86s)
--- PASS: TestAccAWSS3Bucket_AclToGrant (67.94s)
--- PASS: TestAccAWSS3Bucket_basic (37.25s)
--- PASS: TestAccAWSS3Bucket_Bucket_EmptyString (35.95s)
--- PASS: TestAccAWSS3Bucket_Cors_Delete (31.78s)
--- PASS: TestAccAWSS3Bucket_Cors_EmptyOrigin (37.29s)
--- PASS: TestAccAWSS3Bucket_Cors_Update (65.22s)
--- PASS: TestAccAWSS3Bucket_disableDefaultEncryption_whenDefaultEncryptionIsEnabled (62.31s)
--- PASS: TestAccAWSS3Bucket_enableDefaultEncryption_whenAES256IsUsed (37.28s)
--- PASS: TestAccAWSS3Bucket_enableDefaultEncryption_whenTypical (43.14s)
--- PASS: TestAccAWSS3Bucket_forceDestroy (31.61s)
--- PASS: TestAccAWSS3Bucket_forceDestroyWithEmptyPrefixes (31.54s)
--- PASS: TestAccAWSS3Bucket_forceDestroyWithObjectLockEnabled (37.95s)
--- PASS: TestAccAWSS3Bucket_generatedName (35.53s)
--- PASS: TestAccAWSS3Bucket_GrantToAcl (57.50s)
--- PASS: TestAccAWSS3Bucket_LifecycleBasic (86.93s)
--- PASS: TestAccAWSS3Bucket_LifecycleExpireMarkerOnly (62.03s)
--- PASS: TestAccAWSS3Bucket_LifecycleRule_Expiration_EmptyConfigurationBlock (31.01s)
--- PASS: TestAccAWSS3Bucket_Logging (55.35s)
--- PASS: TestAccAWSS3Bucket_namePrefix (35.81s)
--- PASS: TestAccAWSS3Bucket_objectLock (60.93s)
--- PASS: TestAccAWSS3Bucket_Policy (88.67s)
--- PASS: TestAccAWSS3Bucket_Replication (147.39s)
--- PASS: TestAccAWSS3Bucket_ReplicationConfiguration_Rule_Destination_AccessControlTranslation (86.62s)
--- PASS: TestAccAWSS3Bucket_ReplicationConfiguration_Rule_Destination_AddAccessControlTranslation (84.62s)
--- PASS: TestAccAWSS3Bucket_ReplicationExpectVersioningValidationError (28.14s)
--- PASS: TestAccAWSS3Bucket_ReplicationSchemaV2 (152.22s)
--- PASS: TestAccAWSS3Bucket_ReplicationWithoutPrefix (52.74s)
--- PASS: TestAccAWSS3Bucket_ReplicationWithoutStorageClass (51.40s)
--- PASS: TestAccAWSS3Bucket_RequestPayer (63.26s)
--- PASS: TestAccAWSS3Bucket_shouldFailNotFound (15.41s)
--- PASS: TestAccAWSS3Bucket_tagsWithNoSystemTags (118.49s)
--- PASS: TestAccAWSS3Bucket_tagsWithSystemTags (163.94s)
--- PASS: TestAccAWSS3Bucket_UpdateAcl (58.70s)
--- PASS: TestAccAWSS3Bucket_UpdateGrant (91.75s)
--- PASS: TestAccAWSS3Bucket_Versioning (90.14s)
--- PASS: TestAccAWSS3Bucket_Website_Simple (89.22s)
--- PASS: TestAccAWSS3Bucket_WebsiteRedirect (86.48s)
--- PASS: TestAccAWSS3Bucket_WebsiteRoutingRules (63.97s)

--- PASS: TestAccAWSSsmResourceDataSync_basic (15.77s)
--- PASS: TestAccAWSSsmResourceDataSync_update (28.49s)

    TestAccAwsCurReportDefinition_basic: testing.go:684: Step 0 error: errors during apply:

        Error: Error creating AWS Cost And Usage Report Definition: ValidationException: Failed to verify customer bucket permission. accountId= --OMITTED--, bucket name: tf-test-bucket-3532084976228094739, bucket region: us-east-1

    TestAccDataSourceAwsCurReportDefinition_basic: testing.go:684: Step 0 error: errors during apply:

        Error: Error creating AWS Cost And Usage Report Definition: ValidationException: Failed to verify customer bucket permission. accountId= --OMITTED--, bucket name: tf-test-bucket-9147728765044904331, bucket region: us-east-1
```

aws/data_source_aws_cur_report_definition_test.go

@@ -20,15 +20,14 @@ func TestAccDataSourceAwsCurReportDefinition_basic(t *testing.T) {
 
 	reportName := acctest.RandomWithPrefix("tf_acc_test")
 	bucketName := fmt.Sprintf("tf-test-bucket-%d", acctest.RandInt())
-	bucketRegion := "us-east-1"
 
 	resource.ParallelTest(t, resource.TestCase{
 		PreCheck:     func() { testAccPreCheck(t); testAccPreCheckAWSCur(t) },
 		Providers:    testAccProviders,
 		CheckDestroy: testAccCheckAwsCurReportDefinitionDestroy,
 		Steps: []resource.TestStep{
 			{
-				Config: testAccDataSourceAwsCurReportDefinitionConfig_basic(reportName, bucketName, bucketRegion),
+				Config: testAccDataSourceAwsCurReportDefinitionConfig_basic(reportName, bucketName),
 				Check: resource.ComposeTestCheckFunc(
 					testAccDataSourceAwsCurReportDefinitionCheckExists(datasourceName, resourceName),
 					resource.TestCheckResourceAttrPair(datasourceName, "report_name", resourceName, "report_name"),
@@ -60,7 +59,7 @@ func testAccDataSourceAwsCurReportDefinitionCheckExists(datasourceName, resource
 }
 
 // note: cur report definitions are currently only supported in us-east-1
-func testAccDataSourceAwsCurReportDefinitionConfig_basic(reportName string, bucketName string, bucketRegion string) string {
+func testAccDataSourceAwsCurReportDefinitionConfig_basic(reportName string, bucketName string) string {
 	return fmt.Sprintf(`
 provider "aws" {
   region = "us-east-1"
@@ -72,7 +71,6 @@ resource "aws_s3_bucket" "test" {
   bucket        = "%[2]s"
   acl           = "private"
   force_destroy = true
-  region        = "%[3]s"
 }
 
 resource "aws_s3_bucket_policy" "test" {
@@ -124,5 +122,5 @@ resource "aws_cur_report_definition" "test" {
 data "aws_cur_report_definition" "test" {
   report_name = "${aws_cur_report_definition.test.report_name}"
 }
-`, reportName, bucketName, bucketRegion)
+`, reportName, bucketName)
 }

aws/resource_aws_cur_report_definition_test.go

@@ -18,18 +18,17 @@ func TestAccAwsCurReportDefinition_basic(t *testing.T) {
 	defer os.Setenv("AWS_DEFAULT_REGION", oldvar)
 
 	resourceName := "aws_cur_report_definition.test"
-
+	s3BucketResourceName := "aws_s3_bucket.test"
 	reportName := acctest.RandomWithPrefix("tf_acc_test")
 	bucketName := fmt.Sprintf("tf-test-bucket-%d", acctest.RandInt())
-	bucketRegion := "us-east-1"
 
 	resource.ParallelTest(t, resource.TestCase{
 		PreCheck:     func() { testAccPreCheck(t); testAccPreCheckAWSCur(t) },
 		Providers:    testAccProviders,
 		CheckDestroy: testAccCheckAwsCurReportDefinitionDestroy,
 		Steps: []resource.TestStep{
 			{
-				Config: testAccAwsCurReportDefinitionConfig_basic(reportName, bucketName, bucketRegion),
+				Config: testAccAwsCurReportDefinitionConfig_basic(reportName, bucketName),
 				Check: resource.ComposeTestCheckFunc(
 					testAccCheckAwsCurReportDefinitionExists(resourceName),
 					resource.TestCheckResourceAttr(resourceName, "report_name", reportName),
@@ -38,7 +37,7 @@ func TestAccAwsCurReportDefinition_basic(t *testing.T) {
 					resource.TestCheckResourceAttr(resourceName, "additional_schema_elements.#", "1"),
 					resource.TestCheckResourceAttr(resourceName, "s3_bucket", bucketName),
 					resource.TestCheckResourceAttr(resourceName, "s3_prefix", ""),
-					resource.TestCheckResourceAttr(resourceName, "s3_region", bucketRegion),
+					resource.TestCheckResourceAttrPair(resourceName, "s3_region", s3BucketResourceName, "region"),
 					resource.TestCheckResourceAttr(resourceName, "additional_artifacts.#", "2"),
 				),
 			},
@@ -105,7 +104,7 @@ func testAccPreCheckAWSCur(t *testing.T) {
 }
 
 // note: cur report definitions are currently only supported in us-east-1
-func testAccAwsCurReportDefinitionConfig_basic(reportName string, bucketName string, bucketRegion string) string {
+func testAccAwsCurReportDefinitionConfig_basic(reportName string, bucketName string) string {
 	return fmt.Sprintf(`
 provider "aws" {
   region = "us-east-1"
@@ -115,7 +114,6 @@ resource "aws_s3_bucket" "test" {
   bucket        = "%[2]s"
   acl           = "private"
   force_destroy = true
-  region        = "%[3]s"
 }
 
 resource "aws_s3_bucket_policy" "test" {
@@ -163,5 +161,5 @@ resource "aws_cur_report_definition" "test" {
   s3_region                  = "${aws_s3_bucket.test.region}"
   additional_artifacts       = ["REDSHIFT", "QUICKSIGHT"]
 }
-`, reportName, bucketName, bucketRegion)
+`, reportName, bucketName)
 }

aws/resource_aws_s3_bucket.go

@@ -205,7 +205,6 @@ func resourceAwsS3Bucket() *schema.Resource {
 
 			"region": {
 				Type:     schema.TypeString,
-				Optional: true,
 				Computed: true,
 			},
 			"website_endpoint": {
@@ -666,12 +665,7 @@ func resourceAwsS3BucketCreate(d *schema.ResourceData, meta interface{}) error {
 		log.Printf("[DEBUG] S3 bucket %s has canned ACL %s", bucket, acl)
 	}
 
-	var awsRegion string
-	if region, ok := d.GetOk("region"); ok {
-		awsRegion = region.(string)
-	} else {
-		awsRegion = meta.(*AWSClient).region
-	}
+	awsRegion := meta.(*AWSClient).region
 	log.Printf("[DEBUG] S3 bucket create: %s, using region: %s", bucket, awsRegion)
 
 	// Special case us-east-1 region and do not set the LocationConstraint.

aws/resource_aws_s3_bucket_test.go

@@ -435,26 +435,6 @@ func TestAccAWSS3Bucket_generatedName(t *testing.T) {
 	})
 }
 
-func TestAccAWSS3Bucket_region(t *testing.T) {
-	resourceName := "aws_s3_bucket.test"
-	rName := acctest.RandomWithPrefix("tf-acc-test")
-
-	resource.ParallelTest(t, resource.TestCase{
-		PreCheck:     func() { testAccPreCheck(t) },
-		Providers:    testAccProviders,
-		CheckDestroy: testAccCheckAWSS3BucketDestroy,
-		Steps: []resource.TestStep{
-			{
-				Config: testAccAWSS3BucketConfigWithRegion(rName),
-				Check: resource.ComposeTestCheckFunc(
-					testAccCheckAWSS3BucketExists(resourceName),
-					resource.TestCheckResourceAttr(resourceName, "region", testAccGetRegion()),
-				),
-			},
-		},
-	})
-}
-
 func TestAccAWSS3Bucket_acceleration(t *testing.T) {
 	bucketName := acctest.RandomWithPrefix("tf-test-bucket")
 	resourceName := "aws_s3_bucket.bucket"
@@ -3071,17 +3051,6 @@ resource "aws_s3_bucket" "bucket6" {
 `, randInt)
 }
 
-func testAccAWSS3BucketConfigWithRegion(bucketName string) string {
-	return fmt.Sprintf(`
-data "aws_region" "current" {}
-
-resource "aws_s3_bucket" "test" {
-  bucket = %[1]q
-  region = data.aws_region.current.name
-}
-`, bucketName)
-}
-
 func testAccAWSS3BucketWebsiteConfig(bucketName string) string {
 	return fmt.Sprintf(`
 resource "aws_s3_bucket" "bucket" {

aws/resource_aws_ssm_resource_data_sync_test.go

@@ -96,7 +96,6 @@ func testAccSsmResourceDataSyncConfig(rInt int, rName string) string {
 	return fmt.Sprintf(`
 resource "aws_s3_bucket" "hoge" {
   bucket        = "tf-test-bucket-%d"
-  region        = "us-west-2"
   force_destroy = true
 }
 
@@ -150,7 +149,6 @@ func testAccSsmResourceDataSyncConfigUpdate(rInt int, rName string) string {
 	return fmt.Sprintf(`
 resource "aws_s3_bucket" "hoge" {
   bucket        = "tf-test-bucket-%d"
-  region        = "us-west-2"
   force_destroy = true
 }
 

website/docs/guides/version-3-upgrade.html.md

@@ -433,6 +433,28 @@ resource "aws_msk_cluster" "example" {
 
 Previously when importing the `aws_s3_bucket` resource with the [`terraform import` command](/docs/commands/import.html), the Terraform AWS Provider would automatically attempt to import an associated `aws_s3_bucket_policy` resource as well. This automatic resource import has been removed. Use the [`aws_s3_bucket_policy` resource import](/docs/providers/aws/r/s3_bucket_policy.html#import) to import that resource separately.
 
+### region Attribute Is Now Read-Only
+
+The `region` attribute is no longer configurable, but it remains as a read-only attribute. The region of the `aws_s3_bucket` resource is determined by the region of the Terraform AWS Provider, similar to all other resources.
+
+For example, given this previous configuration:
+
+```hcl
+resource "aws_s3_bucket" "example" {
+  # ... other configuration ...
+
+  region = "us-west-2"
+}
+```
+
+An updated configuration:
+
+```hcl
+resource "aws_s3_bucket" "example" {
+  # ... other configuration ...
+}
+```
+
 ## Resource: aws_sns_platform_application
 
 ### platform_credential and platform_principal Arguments No Longer Stored as SHA256 Hash

website/docs/r/s3_bucket.html.markdown

@@ -253,7 +253,6 @@ resource "aws_iam_role_policy_attachment" "replication" {
 
 resource "aws_s3_bucket" "destination" {
   bucket = "tf-test-bucket-destination-12345"
-  region = "eu-west-1"
 
   versioning {
     enabled = true
@@ -264,7 +263,6 @@ resource "aws_s3_bucket" "bucket" {
   provider = "aws.central"
   bucket   = "tf-test-bucket-12345"
   acl      = "private"
-  region   = "eu-central-1"
 
   versioning {
     enabled = true
@@ -349,7 +347,6 @@ The following arguments are supported:
 * `logging` - (Optional) A settings of [bucket logging](https://docs.aws.amazon.com/AmazonS3/latest/UG/ManagingBucketLogging.html) (documented below).
 * `lifecycle_rule` - (Optional) A configuration of [object lifecycle management](http://docs.aws.amazon.com/AmazonS3/latest/dev/object-lifecycle-mgmt.html) (documented below).
 * `acceleration_status` - (Optional) Sets the accelerate configuration of an existing bucket. Can be `Enabled` or `Suspended`.
-* `region` - (Optional) If specified, the AWS region this bucket should reside in. Otherwise, the region used by the callee.
 * `request_payer` - (Optional) Specifies who should bear the cost of Amazon S3 data transfer.
 Can be either `BucketOwner` or `Requester`. By default, the owner of the S3 bucket would incur
 the costs of any data transfer. See [Requester Pays Buckets](http://docs.aws.amazon.com/AmazonS3/latest/dev/RequesterPaysBuckets.html)

website/docs/r/ssm_resource_data_sync.html.markdown

@@ -15,7 +15,6 @@ Provides a SSM resource data sync.
 ```hcl
 resource "aws_s3_bucket" "hoge" {
   bucket = "tf-test-bucket-1234"
-  region = "us-east-1"
 }
 
 resource "aws_s3_bucket_policy" "hoge" {