hible

cache add function
// IncrBy increase counter by num.
IncrBy(key string, num int)
// DecrBy decrease counter by num.
DecrBy(key string, num int)

cache/memcache/memcache.go

@@ -127,6 +127,21 @@ func (rc *Cache) Incr(key string) error {
 	return err
 }
 
+// IncrBy increase counter by num.
+func (rc *Cache) IncrBy(key string, num int) error {
+	if num < 1 {
+		return errors.New("increase num should be a positive number")
+	}
+
+	if rc.conn == nil {
+		if err := rc.connectInit(); err != nil {
+			return err
+		}
+	}
+	_, err := rc.conn.Increment(key, uint64(num))
+	return err
+}
+
 // Decr decrease counter.
 func (rc *Cache) Decr(key string) error {
 	if rc.conn == nil {
@@ -138,6 +153,21 @@ func (rc *Cache) Decr(key string) error {
 	return err
 }
 
+// DecrBy decrease counter by num.
+func (rc *Cache) DecrBy(key string, num int) error {
+	if num < 1 {
+		return errors.New("decrease num should be a positive number")
+	}
+
+	if rc.conn == nil {
+		if err := rc.connectInit(); err != nil {
+			return err
+		}
+	}
+	_, err := rc.conn.Decrement(key, uint64(num))
+	return err
+}
+
 // IsExist check value exists in memcache.
 func (rc *Cache) IsExist(key string) bool {
 	if rc.conn == nil {