fix(client): use grpc-go default dialer for tcp and unix connections

[hown3d]

Closes #4126.

[jedevc]

I think this seems good to me in principle. Though maybe @tonistiigi or @crazy-max have additional context for why we use a custom dialer here, instead of just using the default.

[hown3d]

Is there something missing to review this PR?

[jedevc]

Closing/re-opening to kick CI to rerun against master (since this has been open a while).

Looks like linting is now failing (sorry).

[jedevc]

I think this package should now be included in cmd/buildctl/main.go since npipe is refactored to a connhelper. Otherwise, this connhelper can't actually get used.

I think this is what is causing the windows tests to fail.

[hown3d]

Makes sense. I needed to refactor to support windows and non windows builds, because importing the package in main assumes that it's always build.

When building non-windows and trying to use npipe connections, it will default to an error:
https://github.com/moby/buildkit/pull/4127/files#diff-0010b4ef47621e028d85218a669df091152ba11f4bafee2566797d759dc28214R12-R14

[jedevc]

Rebased.

[jedevc]

Note: this probably shouldn't be for v0.13.0.

[profnandaa]

Thanks for the PR!

The other part is that, try to focus first on the main changes of the PR other than the styling (unless you are changing the same line specifically as part of the functional change). That way, the review can be a little focused.

[profnandaa]

nit: I think the idea was that we try as much as possible to abstract the naming so that it's not platform specific (especially for Windows); that's why we'd gone with just a generic package client. This npipe package is very lean and it's Windows-specific; might be good to go this route only after we've a number of things we are doing with npipe other than just one helper.

[jedevc]

Squashed commits + rebased, and merged 🎉