Fail fast on multi platform build with load

[rumpl]

Avoid doing a build if we cannot load the images at the end.

This doesn't really fix anything but at least users will see the error right away and not after a potentially long build.

[tonistiigi]

This should fail fast already without building. Should block it in moby level if not. edit: nvm: this is a different case where building in container and exporting to docker

For buildx side, this check should be moved to build/build.go so that builds from bake also pass validation.

[tonistiigi]

hmm

buildx/build/build.go

Lines 460 to 462 in 84a734d

	if len(pp) > 1 && !d.Features()[driver.MultiPlatform] {
	return nil, nil, notSupported(d, driver.MultiPlatform)
	}

[rumpl]

Ok so it's building before failing if the driver is docker-container, which has driver.MultiPlatform: true

[tonistiigi]

@rumpl Ah, ok. That is different. Add this extra condition to https://github.com/docker/buildx/blob/master/build/build.go#L415

[tonistiigi]

^

[rumpl]

^

👍 I'm moving right now, will get at this next week, sorry

[tonistiigi]

This does not look correct. Multi-platform builds with docker-container driver are definitely supported. If I understood your description correctly then the condition you want is to check if exporting is happening to docker. Also, we should never check for driver names. There is a features list for that but don't think you need that atm., just check for the exporter.

[rumpl]

I should check that the exporter is “docker” right? Sent from mobile - please excuse tone and brevity

…

On Jun 24, 2021, at 19:59, Tõnis Tiigi ***@***.***> wrote:  @tonistiigi requested changes on this pull request. In build/build.go: > @@ -520,6 +520,10 @@ func toSolveOpt(ctx context.Context, d driver.Driver, multiDriver bool, opt Opti so.FrontendAttrs["platform"] = strings.Join(pp, ",") } + if len(opt.Platforms) != 1 && d.Factory().Name() == "docker-container" { This does not look correct. Multi-platform builds with docker-container driver are definitely supported. If I understood your description correctly then the condition you want is to check if exporting is happening to docker. Also, we should never check for driver names. There is a features list for that but don't think you need that atm., just check for the exporter. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or unsubscribe.

[tonistiigi]

I should check that the exporter is “docker” right?

Correct

[tonistiigi]

Looks correct but move it to line 458 so all the docker exporter handling is in one place.

[crazy-max]

LGTM