fix: worker: Close all storage paths on worker shutdown

[shrenujbansal]

Related Issues

#5227
#7570

Proposed Changes

Add an API to close all paths for a worker which is then used during worker shutdown to properly clear state

Additional Info

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[shrenujbansal]

I'm of the opinion that we should continue execution since shutdown should be best effort and should not be stopped if we can't close some paths
But the linter doesn't allow me ignore the return. Is there a better way to do this here? What are your thoughts?

[geoff-vball]

replace err with _ if you want to explicitly ignore a return value. Leave a helpful comment with why you're doing so :)

In this case we can probably just log the error instead of returning if we want to continue on.

[rjan90]

Tested this today, and it closed the storage path correctly here. Not seeing any errors when running lotus-miner storage list after stopping the lotus-worker.

2022-08-11T11:45:49.630+0200    WARN    stores  paths/index.go:293      Dropping sector storage {"path": "19c858be-9b1a-4ef5-9eaa-5595d4cff6cf", "url": "http://127.0.0.1:3456/remote", "droppedEntries": 0, "droppedPrimaryEntries": 0, "droppedDecls": 0}
2022-08-11T11:45:53.667+0200    WARN    advmgr  sealer/sched_worker.go:90       Worker closing  {"workerid": "a2400659-ece2-4826-a2bd-dc95c9392eb9"}