/usr/local/openresty/lualib/resty/mysql.lua:373: attempt to perform arithmetic on field 'packet_no' (a nil value)

[liangpinglk]

During the process when I utilized the lib., the below error occurred occasionally. What makes me confused is that the value of variable "packet_no" can be "nil". I have no idea why does this kind of error occur, and how to avoid it. Could you pls be so kind to advise on this issue? Thanks.

• openresty version

nginx version: openresty/1.19.3.1

• docker image

openresty/openresty:1.19.3.1-2-buster-fat