diff --git a/storage/mongo.go b/storage/mongo.go
index ed2fec6..2bf0bc5 100644
--- a/storage/mongo.go
+++ b/storage/mongo.go
@@ -2,7 +2,6 @@ package storage
 
 import (
 	"context"
-	"local/cheqbooq/config"
 	"log"
 	"os/exec"
 	"time"
@@ -13,6 +12,7 @@ import (
 
 type Mongo struct {
 	client *mongo.Client
+	ns     string
 }
 
 func init() {
@@ -44,7 +44,7 @@ func init() {
 	}()
 }
 
-func NewMongo(addr string) (*Mongo, error) {
+func NewMongo(ns, addr string) (*Mongo, error) {
 	ctx, can := context.WithTimeout(context.Background(), time.Second*5)
 	defer can()
 
@@ -58,6 +58,7 @@ func NewMongo(addr string) (*Mongo, error) {
 
 	return &Mongo{
 		client: client,
+		ns:     ns,
 	}, client.Ping(ctx, nil)
 }
 
@@ -66,15 +67,15 @@ func (m *Mongo) Close() error {
 }
 
 func (m *Mongo) Account() *mongo.Collection {
-	return m.client.Database(config.StoreNS).Collection("account")
+	return m.client.Database(m.ns).Collection("account")
 }
 
 func (m *Mongo) Balance() *mongo.Collection {
-	return m.client.Database(config.StoreNS).Collection("balance")
+	return m.client.Database(m.ns).Collection("balance")
 }
 
 func (m *Mongo) Transaction() *mongo.Collection {
-	return m.client.Database(config.StoreNS).Collection("transaction")
+	return m.client.Database(m.ns).Collection("transaction")
 }
 
 func (m *Mongo) Find(c *mongo.Collection, where interface{}, next func() interface{}) error {
diff --git a/storage/mongo_test.go b/storage/mongo_test.go
index 76fff3c..489a85f 100644
--- a/storage/mongo_test.go
+++ b/storage/mongo_test.go
@@ -1,10 +1,97 @@
 package storage
 
-import "testing"
+import (
+	"context"
+	"crypto/rand"
+	"encoding/base64"
+	"testing"
+)
 
-func TestMongoNew(t *testing.T) {
-	_, err := NewMongo("mongodb://localhost:27017")
+func testMongoNew(t *testing.T) *Mongo {
+	b := make([]byte, 5)
+	rand.Read(b)
+	m, err := NewMongo(base64.URLEncoding.EncodeToString(b), "mongodb://localhost:27017")
 	if err != nil {
 		t.Fatal(err)
 	}
+	return m
+}
+
+func TestMongoNew(t *testing.T) {
+	if err := testMongoNew(t).Close(); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestMongoFind(t *testing.T) {
+	m := testMongoNew(t)
+	defer m.Close()
+
+	c := m.Account()
+	defer c.Drop(context.TODO())
+	if _, err := c.InsertMany(context.TODO(), []interface{}{
+		map[string]interface{}{"_id": "1", "a": "b"},
+		map[string]interface{}{"_id": "2", "a": "b", "c": "d"},
+		map[string]interface{}{"_id": "3", "c": "d"},
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	cnt := 0
+	inc := func() interface{} {
+		cnt += 1
+		var v interface{}
+		return &v
+	}
+	if err := m.Find(c, map[string]interface{}{"a": "b"}, inc); err != nil {
+		t.Fatal(err)
+	} else if cnt != 2 {
+		t.Fatal(cnt)
+	}
+
+	cnt = 0
+	if err := m.Find(c, map[string]interface{}{"_id": "1"}, inc); err != nil {
+		t.Fatal(err)
+	} else if cnt != 1 {
+		t.Fatal(cnt)
+	}
+
+	cnt = 0
+	if err := m.Find(c, map[string]interface{}{}, inc); err != nil {
+		t.Fatal(err)
+	} else if cnt != 3 {
+		t.Fatal(cnt)
+	}
+}
+
+func TestMongoUpsert(t *testing.T) {
+	m := testMongoNew(t)
+	defer m.Close()
+
+	c := m.Account()
+	defer c.Drop(context.TODO())
+	if _, err := c.InsertMany(context.TODO(), []interface{}{
+		map[string]interface{}{"_id": "1", "a": "b"},
+		map[string]interface{}{"_id": "2", "a": "b", "c": "d"},
+		map[string]interface{}{"_id": "3", "c": "d"},
+	}); err != nil {
+		t.Fatal(err)
+	}
+
+	if n, err := c.EstimatedDocumentCount(context.TODO()); err != nil {
+		t.Fatal(err)
+	} else if n != 3 {
+		t.Fatal(n)
+	}
+
+	if err := m.Upsert(c, map[string]interface{}{"_id": "1"}, map[string]interface{}{"$set": map[string]interface{}{"c": "d"}}); err != nil {
+		t.Fatal(err)
+	}
+
+	mapped := map[string]string{}
+	if err := c.FindOne(context.TODO(), map[string]interface{}{"_id": "1"}).Decode(&mapped); err != nil {
+		t.Fatal(err)
+	} else if mapped["c"] != "d" {
+		t.Fatal(mapped)
+	}
 }
diff --git a/storage/storage.go b/storage/storage.go
index 8fe0fae..752eb55 100644
--- a/storage/storage.go
+++ b/storage/storage.go
@@ -11,7 +11,7 @@ type Storage struct {
 }
 
 func New() (*Storage, error) {
-	mongo, err := NewMongo(fmt.Sprintf("mongodb://%s", strings.TrimPrefix(config.StoreAddr, "mongodb://")))
+	mongo, err := NewMongo(config.StoreNS, fmt.Sprintf("mongodb://%s", strings.TrimPrefix(config.StoreAddr, "mongodb://")))
 	return &Storage{
 		mongo: mongo,
 	}, err