fix issue 4311

client/cache/memory.go

@@ -18,6 +18,8 @@ import (
 	"context"
 	"encoding/json"
 	"errors"
+	"fmt"
+	"strings"
 	"sync"
 	"time"
 )
@@ -68,22 +70,28 @@ func (bc *MemoryCache) Get(ctx context.Context, key string) (interface{}, error)
 		}
 		return itm.val, nil
 	}
-	return nil, nil
+	return nil, errors.New("the key isn't exist")
 }
 
 // GetMulti gets caches from memory.
 // If non-existent or expired, return nil.
 func (bc *MemoryCache) GetMulti(ctx context.Context, keys []string) ([]interface{}, error) {
-	var rc []interface{}
-	for _, name := range keys {
-		val, err := bc.Get(context.Background(), name)
+	rc := make([]interface{}, len(keys))
+	keysErr := make([]string, 0)
+
+	for i, ki := range keys {
+		val, err := bc.Get(context.Background(), ki)
 		if err != nil {
-			rc = append(rc, err)
-		} else {
-			rc = append(rc, val)
+			keysErr = append(keysErr, fmt.Sprintf("key [%s] error: %s", ki, err.Error()))
+			continue
 		}
+		rc[i] = val
 	}
-	return rc, nil
+
+	if len(keysErr) == 0 {
+		return rc, nil
+	}
+	return rc, errors.New(strings.Join(keysErr, "; "))
 }
 
 // Put puts cache into memory.