bug: etcd keepalive function runtime error

[zuiyangqingzhou]

Current Behavior

server-info plugin error occurred when report info

Expected Behavior

No response

Error Logs

2022/04/20 03:33:58 [warn] 17703#17703: *757946 [lua] v3.lua:151: keepalive(): invalid response code: 503. Retrying, context: ngx.timer
2022/04/20 03:34:06 [warn] 17703#17703: *757946 [lua] v3.lua:151: keepalive(): invalid response code: 503. Retrying, context: ngx.timer
2022/04/20 03:34:14 [warn] 17703#17703: *757946 [lua] v3.lua:151: keepalive(): invalid response code: 503. Retrying, context: ngx.timer
2022/04/20 03:34:22 [warn] 17703#17703: *757946 [lua] v3.lua:151: keepalive(): invalid response code: 503. Retrying, context: ngx.timer
2022/04/20 03:34:22 [error] 17703#17703: *757946 lua user thread aborted: runtime error: ...er_v2.1.0_20220420//deps/share/lua/5.1/resty/etcd/v3.lua:158: attempt to index local 'res' (a nil value)
stack traceback:
coroutine 0:
	...er_v2.1.0_20220420//deps/share/lua/5.1/resty/etcd/v3.lua: in function 'keepalive'
	...ffic-gateway/master_v2.1.0_20220420/apisix/core/etcd.lua:370: in function 'keepalive'
	...ay/master_v2.1.0_20220420/apisix/plugins/server-info.lua:217: in function 'report'
	...ay/master_v2.1.0_20220420/apisix/plugins/server-info.lua:279: in function <...ay/master_v2.1.0_20220420/apisix/plugins/server-info.lua:274>
coroutine 1:
	[C]: in function 'thread_wait'
	...traffic-gateway/master_v2.1.0_20220420/apisix/timers.lua:52: in function <...traffic-gateway/master_v2.1.0_20220420/apisix/timers.lua:32>
	[C]: in function 'pcall'
	...fic-gateway/master_v2.1.0_20220420/apisix/core/timer.lua:35: in function <...fic-gateway/master_v2.1.0_20220420/apisix/core/timer.lua:31>
	[C]: in function 'pcall'
	...fic-gateway/master_v2.1.0_20220420/apisix/core/timer.lua:58: in function <...fic-gateway/master_v2.1.0_20220420/apisix/core/timer.lua:51>, context: ngx.timer
2022/04/20 03:34:22 [error] 17703#17703: *757946 [lua] timer.lua:37: failed to run the timer: background err: ...traffic-gateway/master_v2.1.0_20220420/apisix/timers.lua:54: bad argument #2 to 'error' (expected table to have __tostring metamethod), context: ngx.timer

Steps to Reproduce

none

Environment

• APISIX version (run apisix version): 2.10.5
• Operating system (run uname -a): x86_64 GNU/Linux
• OpenResty / Nginx version (run openresty -V or nginx -V): nginx version: openresty/1.19.9.1
• etcd version, if relevant (run curl http://127.0.0.1:9090/v1/server_info): 3.5.0
• APISIX Dashboard version, if relevant:
• Plugin runner version, for issues related to plugin runners:
• LuaRocks version, for installation issues (run luarocks --version):

[spacewander]

Why do you think upgrading the etcd library can solve this problem?

[spacewander]

Look like it is solved in api7/lua-resty-etcd@f75f4c5, which is under 1.6.1

[zuiyangqingzhou]

Look like it is solved in api7/lua-resty-etcd@f75f4c5, which is under 1.6.1

Can version 2.10 be solved by directly upgrading lua-resty-etcd to 1.6.1?

Are there compatibility issues?