Fix pagination for users and users search apis

Signed-off-by: He Weiwei <hweiwei@vmware.com>

src/common/dao/dao_test.go

@@ -318,6 +318,11 @@ func TestListUsers(t *testing.T) {
 	if users2[0].Username != username {
 		t.Errorf("The username in result list does not match, expected: %s, actual: %s", username, users2[0].Username)
 	}
+
+	users3, err := ListUsers(&models.UserQuery{Username: username, Pagination: &models.Pagination{Page: 2, Size: 1}})
+	if len(users3) != 0 {
+		t.Errorf("Expect no user in list, but the acutal length is %d, the list: %+v", len(users3), users3)
+	}
 }
 
 func TestResetUserPassword(t *testing.T) {

src/common/dao/user.go

@@ -106,10 +106,13 @@ func GetTotalOfUsers(query *models.UserQuery) (int64, error) {
 
 // ListUsers lists all users according to different conditions.
 func ListUsers(query *models.UserQuery) ([]models.User, error) {
+	qs := userQueryConditions(query)
+	if query != nil && query.Pagination != nil {
+		offset := (query.Pagination.Page - 1) * query.Pagination.Size
+		qs = qs.Offset(offset).Limit(query.Pagination.Size)
+	}
 	users := []models.User{}
-	_, err := userQueryConditions(query).Limit(-1).
+	_, err := qs.OrderBy("username").All(&users)
-		OrderBy("username").
-		All(&users)
 	return users, err
 }