bug: attempt to index local 'opentracing' (a nil value) when using zipkin plugin

[junhao69535]

Description

this situation is rarely triggered, approximately tens of millions of occurrences only occur a few times. more likely to occur when the request is a websocket.

error msg:
51#51: 4824 failed to run log_by_lua: ...ocal/apisix/plugins/apisix/plugins/zipkin.lua:268: attempt to index local 'opentracing' (a nil value)
stack traceback:
...ocal/apisix/plugins/apisix/plugins/log-zipkin.lua:268: in function 'phase_func'
/usr/local/apisix/apisix/plugin.lua:1139: in function 'run_plugin'
/usr/local/apisix/apisix/plugin.lua:1172: in function 'run_global_rules'
/usr/local/apisix/apisix/init.lua:461: in function 'common_phase'
/usr/local/apisix/apisix/init.lua:870: in function 'http_log_phase'
log_by_lua(nginx.conf:417):2: in main chunk while logging request, client: 10.255.217.88, server: _, request: "GET / HTTP/1.1", upstream: "http://10.212.166.227:9082/", host: "xxx.com"

Environment

• APISIX version (run apisix version): 2.14.1
• Operating system (run uname -a): Linux apisix-b7d9c6fd4-5tn2r 4.19.0-10-amd64 change: added doc of how to load plugin. #1 SMP Debian 4.19.132-1 (2020-07-24) x86_64 GNU/Linux
• OpenResty / Nginx version (run openresty -V or nginx -V): openresty/1.21.4.2
• etcd version, if relevant (run curl http://127.0.0.1:9090/v1/server_info): 3.4.0
• APISIX Dashboard version, if relevant: 3.0.1
• Plugin runner version, for issues related to plugin runners:
• LuaRocks version, for installation issues (run luarocks --version):

[moonming]

I looked at the modification history of this file https://github.com/apache/apisix/commits/master/apisix/plugins/zipkin.lua, and there is no PR to modify this bug. So this bug still exists.
https://github.com/apache/apisix/blob/2.14.1/apisix/plugins/zipkin.lua#L268C2-L268C2 I haven't found a possible cause of this issue, @junhao69535 would you like to fix it?

[junhao69535]

I looked at the modification history of this file https://github.com/apache/apisix/commits/master/apisix/plugins/zipkin.lua, and there is no PR to modify this bug. So this bug still exists. https://github.com/apache/apisix/blob/2.14.1/apisix/plugins/zipkin.lua#L268C2-L268C2 I haven't found a possible cause of this issue, @junhao69535 would you like to fix it?

If it happens again, I will find the cause and fix it.

[junhao69535]

I looked at the modification history of this file https://github.com/apache/apisix/commits/master/apisix/plugins/zipkin.lua, and there is no PR to modify this bug. So this bug still exists. https://github.com/apache/apisix/blob/2.14.1/apisix/plugins/zipkin.lua#L268C2-L268C2 I haven't found a possible cause of this issue, @junhao69535 would you like to fix it?

@moonming , I found the cause and submitted a PR: #10666

[moonming]

I looked at the modification history of this file https://github.com/apache/apisix/commits/master/apisix/plugins/zipkin.lua, and there is no PR to modify this bug. So this bug still exists. https://github.com/apache/apisix/blob/2.14.1/apisix/plugins/zipkin.lua#L268C2-L268C2 I haven't found a possible cause of this issue, @junhao69535 would you like to fix it?

@moonming , I found the cause and submitted a PR: #10666

good work 👍