Adding support to get details for TargetPrefix (#767)

* Adding support to get details for TargetPrefix

* Splitting the GetS3BucketLoggingTarget in 2 functions

* Cleaning up.

* Renaming function back to preserve backwards compatibility

* Fix typo.

examples/terraform-aws-s3-example/main.tf

@@ -75,7 +75,7 @@ resource "aws_s3_bucket" "test_bucket" {
 
   logging {
     target_bucket = aws_s3_bucket.test_bucket_logs.id
-    target_prefix = "/"
+    target_prefix = "TFStateLogs/"
   }
 
   tags = {

examples/terraform-aws-s3-example/outputs.tf

@@ -8,4 +8,8 @@ output "bucket_arn" {
 
 output "logging_target_bucket" {
   value = tolist(aws_s3_bucket.test_bucket.logging)[0].target_bucket
+}
+
+output "logging_target_prefix" {
+  value = tolist(aws_s3_bucket.test_bucket.logging)[0].target_prefix
 }

modules/aws/s3.go

@@ -261,15 +261,16 @@ func EmptyS3BucketE(t testing.TestingT, region string, name string) error {
 	return err
 }
 
-// GetS3BucketLoggingTarget fetches the given bucket's logging configuration status and returns it as a string
+// GetS3BucketLoggingTarget fetches the given bucket's logging target bucket and returns it as a string
 func GetS3BucketLoggingTarget(t testing.TestingT, awsRegion string, bucket string) string {
 	loggingTarget, err := GetS3BucketLoggingTargetE(t, awsRegion, bucket)
 	require.NoError(t, err)
 
 	return loggingTarget
 }
 
-// GetS3BucketLoggingE fetches the given bucket's versioning configuration status and returns it as a string
+// GetS3BucketLoggingTargetE fetches the given bucket's logging target bucket and returns it as the following string:
+// `TargetBucket` of the `LoggingEnabled` property for an S3 bucket
 func GetS3BucketLoggingTargetE(t testing.TestingT, awsRegion string, bucket string) (string, error) {
 	s3Client, err := NewS3ClientE(t, awsRegion)
 	if err != nil {
@@ -291,6 +292,37 @@ func GetS3BucketLoggingTargetE(t testing.TestingT, awsRegion string, bucket stri
 	return aws.StringValue(res.LoggingEnabled.TargetBucket), nil
 }
 
+// GetS3BucketLoggingTargetPrefix fetches the given bucket's logging object prefix and returns it as a string
+func GetS3BucketLoggingTargetPrefix(t testing.TestingT, awsRegion string, bucket string) string {
+	loggingObjectTargetPrefix, err := GetS3BucketLoggingTargetPrefixE(t, awsRegion, bucket)
+	require.NoError(t, err)
+
+	return loggingObjectTargetPrefix
+}
+
+// GetS3BucketLoggingTargetPrefixE fetches the given bucket's logging object prefix and returns it as the following string:
+// `TargetPrefix` of the `LoggingEnabled` property for an S3 bucket
+func GetS3BucketLoggingTargetPrefixE(t testing.TestingT, awsRegion string, bucket string) (string, error) {
+	s3Client, err := NewS3ClientE(t, awsRegion)
+	if err != nil {
+		return "", err
+	}
+
+	res, err := s3Client.GetBucketLogging(&s3.GetBucketLoggingInput{
+		Bucket: &bucket,
+	})
+
+	if err != nil {
+		return "", err
+	}
+
+	if res.LoggingEnabled == nil {
+		return "", S3AccessLoggingNotEnabledErr{bucket, awsRegion}
+	}
+
+	return aws.StringValue(res.LoggingEnabled.TargetPrefix), nil
+}
+
 // GetS3BucketVersioning fetches the given bucket's versioning configuration status and returns it as a string
 func GetS3BucketVersioning(t testing.TestingT, awsRegion string, bucket string) string {
 	versioningStatus, err := GetS3BucketVersioningE(t, awsRegion, bucket)

test/terraform_aws_s3_example_test.go

@@ -64,5 +64,9 @@ func TestTerraformAwsS3Example(t *testing.T) {
 	// Verify that our bucket has server access logging TargetBucket set to what's expected
 	loggingTargetBucket := aws.GetS3BucketLoggingTarget(t, awsRegion, bucketID)
 	expectedLogsTargetBucket := fmt.Sprintf("%s-logs", bucketID)
+	loggingObjectTargetPrefix := aws.GetS3BucketLoggingTargetPrefix(t, awsRegion, bucketID)
+	expectedLogsTargetPrefix := "TFStateLogs/"
+
 	assert.Equal(t, expectedLogsTargetBucket, loggingTargetBucket)
+	assert.Equal(t, expectedLogsTargetPrefix, loggingObjectTargetPrefix)
 }