diff --git a/plugins/op_waf/waf/lua/common.lua b/plugins/op_waf/waf/lua/common.lua
index 0e0da3d5c..1b2ba9f88 100644
--- a/plugins/op_waf/waf/lua/common.lua
+++ b/plugins/op_waf/waf/lua/common.lua
@@ -34,7 +34,7 @@ end
 
 function _M.getInstance(self)
     if rawget(self, "instance") == nil then
-        rawset(self, "instance", self.new())
+        rawset(self, "instance", self:new())
     end
     assert(self.instance ~= nil)
     return self.instance
diff --git a/plugins/op_waf/waf/lua/init.lua b/plugins/op_waf/waf/lua/init.lua
index e622c476d..b05be575e 100644
--- a/plugins/op_waf/waf/lua/init.lua
+++ b/plugins/op_waf/waf/lua/init.lua
@@ -1,8 +1,10 @@
+
 local json = require "cjson"
 local ngx_match = ngx.re.find
 
 local __C = require "common"
 
+-- print(json.encode(__C))
 local C = __C:getInstance()
 
 local config = require "waf_config"