Panic on mattermost ratelimit

[42wim]

I don't really care about slack, so I never looked into it, and when it crashes systemd restarts it anyway. But my logs seem to show the same errors (not or not only at login). The VM it's running on has 5GB ram + 4GB swap free.

Dec 30 16:11:29 mattermost matterircd[4547]: slack-go/slack2021/12/30 16:11:29 websocket_managed_conn.go:343: Sending PING  65
Dec 30 16:11:29 mattermost matterircd[4547]: slack-go/slack2021/12/30 16:11:29 websocket_managed_conn.go:387: Incoming Event: {"type":"pong","timestamp":1640880689,"reply_to":65}
Dec 30 16:11:59 mattermost matterircd[4547]: slack-go/slack2021/12/30 16:11:59 websocket_managed_conn.go:343: Sending PING  66
Dec 30 16:11:59 mattermost matterircd[4547]: slack-go/slack2021/12/30 16:11:59 websocket_managed_conn.go:387: Incoming Event: {"type":"pong","timestamp":1640880719,"reply_to":66}
Dec 30 16:12:29 mattermost matterircd[4547]: slack-go/slack2021/12/30 16:12:29 websocket_managed_conn.go:343: Sending PING  67
Dec 30 16:12:29 mattermost matterircd[4547]: slack-go/slack2021/12/30 16:12:29 websocket_managed_conn.go:387: Incoming Event: {"type":"pong","timestamp":1640880749,"reply_to":67}
Dec 30 16:12:49 mattermost matterircd[4547]: panic: runtime error: invalid memory address or nil pointer dereference
Dec 30 16:12:49 mattermost matterircd[4547]: [signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x83caee]
Dec 30 16:12:49 mattermost matterircd[4547]: goroutine 3165 [running]:
Dec 30 16:12:49 mattermost matterircd[4547]: github.com/matterbridge/matterclient.(*Client).HandleRatelimit(0xc0000224d0, {0x9c6247, 0x1a}, 0xc0000b16c0)
Dec 30 16:12:49 mattermost matterircd[4547]:         /home/fisch/.cache/pikaur/build/matterircd/src/src/github.com/42wim/matterircd/vendor/github.com/matterbridge/matterclient/matterclient.go:717 +0x2e
Dec 30 16:12:49 mattermost matterircd[4547]: github.com/matterbridge/matterclient.(*Client).UpdateChannelsTeam(0xc0005182d0, {0xc0007969c0, 0xc00324cd20})
Dec 30 16:12:49 mattermost matterircd[4547]:         /home/fisch/.cache/pikaur/build/matterircd/src/src/github.com/42wim/matterircd/vendor/github.com/matterbridge/matterclient/channels.go:233 +0x231
Dec 30 16:12:49 mattermost matterircd[4547]: github.com/matterbridge/matterclient.(*Client).UpdateChannels(0xc0005182d0)
Dec 30 16:12:49 mattermost matterircd[4547]:         /home/fisch/.cache/pikaur/build/matterircd/src/src/github.com/42wim/matterircd/vendor/github.com/matterbridge/matterclient/channels.go:250 +0x2e
Dec 30 16:12:49 mattermost matterircd[4547]: github.com/42wim/matterircd/bridge/mattermost6.(*Mattermost).UpdateChannels(0xc0049f0500)
Dec 30 16:12:49 mattermost matterircd[4547]:         /home/fisch/.cache/pikaur/build/matterircd/src/src/github.com/42wim/matterircd/bridge/mattermost6/mattermost.go:239 +0x1c
Dec 30 16:12:49 mattermost matterircd[4547]: created by github.com/42wim/matterircd/bridge/mattermost6.(*Mattermost).checkWsActionMessage
Dec 30 16:12:49 mattermost matterircd[4547]:         /home/fisch/.cache/pikaur/build/matterircd/src/src/github.com/42wim/matterircd/bridge/mattermost6/mattermost.go:166 +0xf5
Dec 30 16:12:49 mattermost systemd[1]: matterircd.service: Main process exited, code=exited, status=2/INVALIDARGUMENT
Dec 30 16:12:49 mattermost systemd[1]: matterircd.service: Failed with result 'exit-code'.
Dec 30 16:12:49 mattermost systemd[1]: matterircd.service: Consumed 43.048s CPU time.
Dec 30 16:13:04 mattermost systemd[1]: matterircd.service: Scheduled restart job, restart counter is at 3.
Dec 30 16:13:04 mattermost systemd[1]: Stopped minimal IRC server which integrates with mattermost and slack.
Dec 30 16:13:04 mattermost systemd[1]: matterircd.service: Consumed 43.048s CPU time.
Dec 30 16:13:04 mattermost systemd[1]: Started minimal IRC server which integrates with mattermost and slack.
Dec 30 16:13:04 mattermost matterircd[4592]: time="2021-12-30T16:13:04Z" level=info msg="Running version 0.25.0 " module=matterircd

Originally posted by @Zauberfisch in https://github.com/42wim/matterircd/issues/455#issuecomment-1003644542