diff --git a/lib/dingtalk/api/sns.rb b/lib/dingtalk/api/sns.rb
index b537dad..85e432c 100644
--- a/lib/dingtalk/api/sns.rb
+++ b/lib/dingtalk/api/sns.rb
@@ -1,10 +1,51 @@
 module Dingtalk
   module Api
-    class Sns
+    class Sns < Base
+      ACCESS_TOKEN = "sns_access_token"
+
       def initialize
         @app_id = Dingtalk.sns_app_id
         @app_secret = Dingtalk.sns_app_secret
       end
+
+      def access_token
+        token = redis.get(ACCESS_TOKEN)
+        token.to_s.empty? ? set_access_token : token
+      end
+
+      def set_access_token
+        res = http_get("gettoken?appid=#{@app_id}&appsecret=#{@app_secret}")
+        redis.set(ACCESS_TOKEN, res['access_token'])
+        redis.expire(key, 7200)
+        redis.get(ACCESS_TOKEN)
+      end
+
+      def get_persistent_code(code)
+        params = { tmp_auth_code: code }
+        http_post("get_persistent_code?access_token=#{access_token}", params)
+      end
+
+      def get_sns_token(openid, persistent_code)
+        params = {
+          openid: openid,
+          persistent_code: persistent_code
+        }
+
+        http_post("get_sns_token?access_token=#{access_token}", params)
+      end
+
+      def get_user_info(sns_token)
+        http_get("getuserinfo?sns_token=#{sns_token}")
+      end
+
+      private
+        def default_params
+          {}
+        end
+
+        def base_url
+          'sns'
+        end
     end
   end
 end
--
libgit2 0.21.0