diff --git a/composer.json b/composer.json
index 46c3897..f422ce2 100644
--- a/composer.json
+++ b/composer.json
@@ -8,6 +8,9 @@
   "autoload": {
     "psr-4": {
       "InternalApi\\": "src/"
-    }
+    },
+    "files": [
+      "helpers.php"
+    ]
   }
 }
diff --git a/src/Client.php b/src/Client.php
index dbc6758..f695e4c 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -39,23 +39,13 @@ class Client
         $client = new \GuzzleHttp\Client($config);
         $params['appid'] = $config['appid'];
         $params['timestamp'] = time();
-        $params['sign'] = $this->sign($params);
+        $key = $this->config[$this->currentApp]['secret'];
+        $params['sign'] = sign($params, $key);
         $resp = $client->post($uri, ['form_params' => $params]);
         if ($resp->getStatusCode() == 200) {
             return \GuzzleHttp\json_decode($resp->getBody(), true);
-        } else {
-            throw new \Exception('request failed');
         }
-    }
-
-    protected function sign($params)
-    {
-        $key = $this->config[$this->currentApp]['secret'];
-
-        unset($params['sign']);
-        ksort($params);
-        $str = http_build_query($params, null, '&');
-        return md5($str . $key);
+        return false;
     }
 
 }
\ No newline at end of file
diff --git a/src/Middleware/InternalApi.php b/src/Middleware/InternalApi.php
index dbd520b..8cafe7d 100644
--- a/src/Middleware/InternalApi.php
+++ b/src/Middleware/InternalApi.php
@@ -5,6 +5,7 @@ namespace InternalApi\Middleware;
 use Closure;
 use Illuminate\Http\JsonResponse;
 use Illuminate\Support\Str;
+use function InternalApi\sign;
 
 class InternalApi
 {
@@ -34,22 +35,29 @@ class InternalApi
         $params = $request->all();
 
         if (empty($params['appid'])) {
-            $data = ['error' => '参数错误',];
+            $data = ['error' => 'require appid',];
             return new JsonResponse($data, 403);
         }
 
         if (empty($params['timestamp'])) {
-            $data = ['error' => '签名已过有效期',];
+            $data = ['error' => 'require time',];
             return new JsonResponse($data, 403);
         } elseif (intval($params['timestamp']) + 60 < time()) {
-            $data = ['error' => '签名已过有效期',];
+            $data = ['error' => 'sign expired',];
             return new JsonResponse($data, 403);
         }
 
-        $sign = $this->sign($params);
+        $key = config('internal_api.server.' . $params['appid']);
+
+        if (empty($key)) {
+            $data = ['error' => 'config error',];
+            return new JsonResponse($data, 403);
+        }
+
+        $sign = sign($params, $key);
         if ($sign != $params['sign']) {
             $data = [
-                'error' => '签名错误',
+                'error' => 'sign error',
             ];
             return new JsonResponse($data, 403);
         }
@@ -57,13 +65,4 @@ class InternalApi
         return $next($request);
     }
 
-    protected function sign($params)
-    {
-        $key = config('internal_api.server.' . $params['appid']);
-        unset($params['sign']);
-        ksort($params);
-        $str = http_build_query($params, null, '&');
-        return md5($str . $key);
-    }
-
 }
diff --git a/src/helpers.php b/src/helpers.php
new file mode 100644
index 0000000..c15772c
--- /dev/null
+++ b/src/helpers.php
@@ -0,0 +1,17 @@
+<?php
+
+namespace InternalApi;
+
+/**
+ * 签名
+ * @param $params
+ * @param $key
+ * @return string
+ */
+function sign($params, $key)
+{
+    unset($params['sign']);
+    ksort($params);
+    $str = http_build_query($params, null, '&');
+    return md5($str . $key);
+}
\ No newline at end of file