Use buildkit's gitutil package to detect remote git files

[jedevc]

🛠️ Fixes #1708.

BuildKit's gitutil package behaves slightly differently than moby's urlutil, so we should rely on BuildKit's gitutil when detecting URLs to avoid cases of accidentally producing invalid build requests that can confuse users.

[crazy-max]

I think we also need changes in

buildx/bake/remote.go

Lines 86 to 129 in 6535f16

	func IsRemoteURL(url string) bool {
	if _, _, ok := detectHTTPContext(url); ok {
	return true
	}
	if _, ok := detectGitContext(url); ok {
	return true
	}
	return false
	}
	func detectHTTPContext(url string) (*llb.State, string, bool) {
	if httpPrefix.MatchString(url) {
	httpContext := llb.HTTP(url, llb.Filename("context"), llb.WithCustomName("[internal] load remote build context"))
	return &httpContext, "context", true
	}
	return nil, "", false
	}
	func detectGitContext(ref string) (*llb.State, bool) {
	found := false
	if httpPrefix.MatchString(ref) && gitURLPathWithFragmentSuffix.MatchString(ref) {
	found = true
	}
	for _, prefix := range []string{"git://", "github.com/", "git@"} {
	if strings.HasPrefix(ref, prefix) {
	found = true
	break
	}
	}
	if !found {
	return nil, false
	}
	parts := strings.SplitN(ref, "#", 2)
	branch := ""
	if len(parts) > 1 {
	branch = parts[1]
	}
	gitOpts := []llb.GitOption{llb.WithCustomName("[internal] load git source " + ref)}
	st := llb.Git(parts[0], branch, gitOpts...)
	return &st, true
	}

[jedevc]

I think we should be able to replace the method there with the new build.IsRemoteURL function (just pushed a commit to do this).

We probably also want to update detectGitContext to align with buildkit, but we should do that by exposing that method to be public first (will open a buildkit-side PR to do that).

[crazy-max]

We probably also want to update detectGitContext to align with buildkit, but we should do that by exposing that method to be public first (will open a buildkit-side PR to do that).

Yes let's do this in a follow-up.