add RetryChecker interface

job/error/error.go

@@ -0,0 +1,23 @@
+/*
+   Copyright (c) 2016 VMware, Inc. All Rights Reserved.
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package error
+
+// RetryChecker checks whether a job should retry if encounters an error
+type RetryChecker interface {
+	// Retry : if the error can be disappear after retrying the job, Retry
+	// returns true
+	Retry(error) bool
+}

job/replication/error.go

@@ -19,8 +19,12 @@ import (
 	"net"
 )
 
-// ShouldRetry determines whether a job should be retried when an error occurred
-func ShouldRetry(err error) bool {
+// ReplicaRetryChecker determines whether a job should be retried when an error occurred
+type ReplicaRetryChecker struct {
+}
+
+// Retry ...
+func (r *ReplicaRetryChecker) Retry(err error) bool {
 	return isTemporary(err)
 }