bug: Consul lock does not receive signals if lock not acquired

[palesiak]

Fix for #4439, where consul lock does not receive signal if lock has not been acquired. The struct for cmd in command/lock/lock.go has a shutdownCh channel that is not populated on creation. This passes in that channel so it can receive/handle them

cc @slackpad @preetapan

[hashicorp-cla]

All committers have signed the CLA.

[freddygv]

Hi @palesiak thanks for the contribution. This solution is a good first step.

The remaining concern to address is that if the shutdown signal is received while executing a blocking query against the API, consul lock won't exit until after that query times out. This will take 15s by default, but could be longer if configured with the -timeout flag.

Let me know if you would like some suggestions regarding how to approach this.

[palesiak]

Let me know if you would like some suggestions regarding how to approach this.

@freddygv Yes, please! I would love some suggestions. I apologize for not responding to this ticket for so long, as I've been heavily loaded with my day job.

[freddygv]

Hi @palesiak after revisiting this, I don't think that we need to handle the case of aborting during a blocking query.

Going to merge your changes as they are. Thanks again for submitting the PR.