Fix default cluster tag validation (#1380)

Author: deliahu

pkg/types/clusterconfig/clusterconfig.go

@@ -626,9 +626,14 @@ func (cc *Config) Validate(awsClient *aws.Client) error {
 		}
 	}
 
-	for tagName := range cc.Tags {
+	for tagName, tagValue := range cc.Tags {
 		if strings.HasPrefix(tagName, "cortex.dev/") {
-			return errors.Wrap(cr.ErrorCantHavePrefix(tagName, "cortex.dev/"), TagsKey)
+			if tagName != ClusterNameTag {
+				return errors.Wrap(cr.ErrorCantHavePrefix(tagName, "cortex.dev/"), TagsKey)
+			}
+			if tagValue != cc.ClusterName {
+				return errors.Wrap(ErrorCantOverrideDefaultTag(), TagsKey)
+			}
 		}
 	}
 	cc.Tags[ClusterNameTag] = cc.ClusterName

pkg/types/clusterconfig/errors.go

@@ -52,6 +52,7 @@ const (
 	ErrInvalidInstanceType                    = "clusterconfig.invalid_instance_type"
 	ErrIOPSNotSupported                       = "clusterconfig.iops_not_supported"
 	ErrIOPSTooLarge                           = "clusterconfig.iops_too_large"
+	ErrCantOverrideDefaultTag                 = "clusterconfig.cant_override_default_tag"
 	ErrSSLCertificateARNNotFound              = "clusterconfig.ssl_certificate_arn_not_found"
 )
 
@@ -235,6 +236,13 @@ func ErrorIOPSTooLarge(iops int64, volumeSize int64) error {
 	})
 }
 
+func ErrorCantOverrideDefaultTag() error {
+	return errors.WithStack(&errors.Error{
+		Kind:    ErrCantOverrideDefaultTag,
+		Message: fmt.Sprintf("the \"%s\" tag cannot be overridden (it is set by default, and will always be equal to your cluster name)", ClusterNameTag),
+	})
+}
+
 func ErrorSSLCertificateARNNotFound(sslCertificateARN string, region string) error {
 	return errors.WithStack(&errors.Error{
 		Kind:    ErrSSLCertificateARNNotFound,