bug fix

@@ -44,7 +44,7 @@ function do_degrade()
   local method = http_request.get_req_param("method")     
   
   if  limit_ip_config and limit_ip_config.degrade_methods then
-    if limit_ip_config.degrade_methods[method]~=nil then
+    if contains(limit_ip_config.degrade_methods,method) then
                 ngx.log(ngx.ERR, "method is degraded.", method)
                 ngx.header["Content-Type"]="application/json;charset=utf-8"
                 local rsp_body = '{"code":9999991,"message":"limited"}'
@@ -54,6 +54,13 @@ function do_degrade()
   end
 end
 
+function contains(t, e)
+  for i = 1,#t do
+    if t[i] == e then return true end
+  end
+  return false
+end
+
 -------- function: doing rate limit by key[interface]-----
 function rate_limit()