Add check for period and das in bucketname (#1097)

The bucket name cannot contain underscores, end with a dash, have consecutive periods, or use dashes adjacent to periods.
Ref : https://docs.aws.amazon.com/awscloudtrail/latest/userguide/cloudtrail-s3-bucket-naming-requirements.html

pkg/s3utils/utils.go

@@ -282,7 +282,7 @@ func checkBucketNameCommon(bucketName string, strict bool) (err error) {
 	if ipAddress.MatchString(bucketName) {
 		return errors.New("Bucket name cannot be an ip address")
 	}
-	if strings.Contains(bucketName, "..") {
+	if strings.Contains(bucketName, "..") || strings.Contains(bucketName, ".-") || strings.Contains(bucketName, "-.") {
 		return errors.New("Bucket name contains invalid characters")
 	}
 	if strict {

pkg/s3utils/utils_test.go

@@ -335,6 +335,8 @@ func TestIsValidBucketName(t *testing.T) {
 		{"my", errors.New("Bucket name cannot be smaller than 3 characters"), false},
 		{"", errors.New("Bucket name cannot be empty"), false},
 		{"my..bucket", errors.New("Bucket name contains invalid characters"), false},
+		{"my.-bucket", errors.New("Bucket name contains invalid characters"), false},
+		{"my-.bucket", errors.New("Bucket name contains invalid characters"), false},
 		{"192.168.1.168", errors.New("Bucket name cannot be an ip address"), false},
 		{":bucketname", errors.New("Bucket name contains invalid characters"), false},
 		{"_bucketName", errors.New("Bucket name contains invalid characters"), false},
@@ -381,6 +383,8 @@ func TestIsValidBucketNameStrict(t *testing.T) {
 		{"my", errors.New("Bucket name cannot be smaller than 3 characters"), false},
 		{"", errors.New("Bucket name cannot be empty"), false},
 		{"my..bucket", errors.New("Bucket name contains invalid characters"), false},
+		{"my.-bucket", errors.New("Bucket name contains invalid characters"), false},
+		{"my-.bucket", errors.New("Bucket name contains invalid characters"), false},
 		{"192.168.1.168", errors.New("Bucket name cannot be an ip address"), false},
 		{"Mybucket", errors.New("Bucket name contains invalid characters"), false},
 		{"my.bucket.com", nil, true},