add verify_user function

app/services/users_service.rb

@@ -340,4 +340,17 @@ class UsersService
 
   end
 
+  # add by zxh
+  # verifyUser by login and password
+  # if correct: return user object
+  # else: return nil
+  def verify_user login, password
+    user = User.find_by_login(login)
+    if user.check_password?(password)
+      return user
+    end
+    nil
+  end
+  # add by zxh end
+
 end