refactor(container): Migrate to std lib context package

[Rahul-Lashkari]

• replaced the deprecated golang.org/x/net/context with the standard library context package
• removed defaultContext() and fixed context leaks
• make format, tidy, test checked

[dims]

ci job fail :(

Run source build/config/plain.sh
>> upgrading golangci-lint from  to 2.6.2
golangci/golangci-lint info checking GitHub for tag 'v2.6.2'
golangci/golangci-lint info found version: 2.6.2 for v2.6.2/linux/amd64
golangci/golangci-lint info installed /home/runner/go/bin/golangci-lint
>> running golangci-lint using configuration at .golangci.yml
Error: container/docker/docker.go:37:7: lostcancel: the cancel function returned by context.WithTimeout should be called, not discarded, to avoid a context leak (govet)
	ctx, _ := context.WithTimeout(context.Background(), dockerTimeout)
	     ^
Error: container/docker/plugin.go:60:8: lostcancel: the cancel function returned by context.WithTimeout should be called, not discarded, to avoid a context leak (govet)
		ctx, _ := context.WithTimeout(context.Background(), startupTimeout)
		     ^
2 issues:
* govet: 2
make: *** [Makefile:89: lint] Error 1
Error: Process completed with exit code 2.

[thaJeztah]

ci job fail :(

Looks like it's an existing issue that wasn't detected by the linter due to the legacy context.

But the linter definitely is correct, and the existing implementation doesn't look good. Perhaps the defaultContext utility should either be removed, or otherwise updated to return the cancel, so that callers can handle the defer cancel(). Given that it's a very shallow wrapper, perhaps removing the utility, and inlining the code where it's used would be more transparent;

cadvisor/container/docker/docker.go

Lines 35 to 38 in fba17be

	func defaultContext() context.Context {
	ctx, _ := context.WithTimeout(context.Background(), dockerTimeout)
	return ctx
	}

@Rahul-Lashkari can you look at making those changes?

[Rahul-Lashkari]

ci job fail :(

Looks like it's an existing issue that wasn't detected by the linter due to the legacy context.

But the linter definitely is correct, and the existing implementation doesn't look good. Perhaps the defaultContext utility should either be removed, or otherwise updated to return the cancel, so that callers can handle the defer cancel(). Given that it's a very shallow wrapper, perhaps removing the utility, and inlining the code where it's used would be more transparent;

cadvisor/container/docker/docker.go

Lines 35 to 38 in fba17be

	func defaultContext() context.Context {
	ctx, _ := context.WithTimeout(context.Background(), dockerTimeout)
	return ctx
	}

@Rahul-Lashkari can you look at making those changes?

yeah sure on it! thanks for guidance!

[Rahul-Lashkari]

PTAL!

[thaJeztah]

Thanks! left some minor comments; also if you could squash the commits, so that there's a single commit in the PR

I'm not a maintainer on this repository, so can't trigger CI to run 😅

[thaJeztah]

LGTM, thanks!

[Rahul-Lashkari]

thanks for merging!