modify response

@@ -14,6 +14,9 @@ function do_degrade()
   for i, v in ipairs(degrade_methods) do
         if method == v 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"}'
+                ngx.say(rsp_body)
                 ngx.exit(ngx.HTTP_OK)
         end
   end