The dedicated service ocis nats server runs panic when stopping.

[2403905]

Describe the bug

The dedicated service ocis nats server runs panic when stopping.

Steps to reproduce

1. Run ocis/bin/ocis nats server
2. Stop control + c

Expected behavior

The service stopped. No errors.

Actual behavior

$ ocis/bin/ocis nats server
2024/10/21 12:48:55 ERROR failed to set GOMEMLIMIT package=github.com/KimMachineGun/automemlimit/memlimit error="failed to set GOMEMLIMIT: cgroups is not supported on this system"
^C{"level":"error","service":"nats","time":"2024-10-21T12:49:09+02:00","message":"Shutting down server"}
panic: close of nil channel

goroutine 1 [running]:
github.com/nats-io/nats-server/v2/server.(*Server).shutdownEventing(0xc0006c0888)
	/Users/roman/go/pkg/mod/github.com/nats-io/nats-server/[email protected]/server/events.go:1738 +0x166
github.com/nats-io/nats-server/v2/server.(*Server).Shutdown(0xc0006c0888)
	/Users/roman/go/pkg/mod/github.com/nats-io/nats-server/[email protected]/server/server.go:2430 +0x52
github.com/owncloud/ocis/v2/services/nats/pkg/server/nats.(*NATSServer).Shutdown(...)
	/Users/roman/projects/owncloud/ocis/services/nats/pkg/server/nats/nats.go:48
github.com/owncloud/ocis/v2/services/nats/pkg/command.Server.func2.3({0x0, 0x0})
	/Users/roman/projects/owncloud/ocis/services/nats/pkg/command/server.go:106 +0x74
github.com/oklog/run.(*Group).Run(0xc00181f3c8)
	/Users/roman/go/pkg/mod/github.com/oklog/[email protected]/group.go:47 +0x17d
github.com/owncloud/ocis/v2/services/nats/pkg/command.Server.func2(0xc000f8c8c0)
	/Users/roman/projects/owncloud/ocis/services/nats/pkg/command/server.go:110 +0xb5e
github.com/urfave/cli/v2.(*Command).Run(0xc0014ac6e0, 0xc000f8c8c0, {0xc0012a48d0, 0x1, 0x1})
	/Users/roman/go/pkg/mod/github.com/urfave/cli/[email protected]/command.go:276 +0x97d
github.com/urfave/cli/v2.(*Command).Run(0xc0014acb00, 0xc00144a680, {0xc001411ea0, 0x2, 0x2})
	/Users/roman/go/pkg/mod/github.com/urfave/cli/[email protected]/command.go:269 +0xbb7
github.com/urfave/cli/v2.(*Command).Run(0xc0014b7b80, 0xc00144a5c0, {0xc00011c780, 0x3, 0x3})
	/Users/roman/go/pkg/mod/github.com/urfave/cli/[email protected]/command.go:269 +0xbb7
github.com/urfave/cli/v2.(*App).RunContext(0xc0005b9c00, {0x1068cee00, 0xc00144a480}, {0xc00011c780, 0x3, 0x3})
	/Users/roman/go/pkg/mod/github.com/urfave/cli/[email protected]/app.go:333 +0x5a5
github.com/owncloud/ocis/v2/ocis/pkg/command.Execute()
	/Users/roman/projects/owncloud/ocis/ocis/pkg/command/root.go:32 +0x1ea
main.main()
	/Users/roman/projects/owncloud/ocis/ocis/cmd/ocis/main.go:11 +0x13

[2403905]

@kobergj The nats server itself runs signal handling that the Shutdown() call in the ocis code is redundant.
Or we can turn the nats signal handling off natsOpts.NoSigs = true and keep the Shutdown() on ower own control.
What do you prefer?

https://github.com/nats-io/nats-server/blob/5fba928d21cd8fee0e5924f90e39f0bc8d39b5d5/server/server.go#L904

[kobergj]

Both solutions are fine for me. If you have a strong opinion go for it. Otherwise let's just use natsOpts.NoSigs = true.