support building docker images using BuildKit

[helmlover]

The claim "Docker [...] Works out of the box." is no longer true.
That is because docker now uses BuildKit per default, while the BuildKit Dockerfile syntax is not supported when building docker images with testcontainers-node (e.g. with GenericContainer.fromDockerfile(buildContext).build())

When building a Dockerfile containing BuildKit-features e.g.

RUN--mount=type=cache,id=maven,target=/root/.m2/repository mvn --batch-mode --no-transfer-progress dependency:resolve dependency:resolve-plugins

through testcontains-node (with export 'DEBUG=testcontainers*'), the output currently looks like:

2023-05-12T08:52:02.265Z testcontainers:build [localhost/43420fa7dc4a:2c9e53cede2c] {"errorDetail":{"message":"the --mount option requires BuildKit. Refer to https://docs.docker.com/go/buildkit/ to learn how to build images with BuildKit enabled"},"error":"the --mount option requires BuildKit. Refer to https://docs.docker.com/go/buildkit/ to learn how to build images with BuildKit enabled"}

Exporting export DOCKER_BUILDKIT=1 does not change the problem/output.

PS: Sibling issue in testcontainers-java: testcontainers/testcontainers-java#2857

[cristianrgreco]

Hi @helmlover, see the parent issue: docker/for-linux#1136. BuildKit does not yet seem supported over the Docker HTTP API, as such is only currently available via the CLI.

[osa0805]

Hi,
Is there a plan to add this support ?

[praveensvsrk]

+1, we need support for this....curious if there a workaround available to achieve the RUN cache like functionality without buildkit features?

[silh]

It looks like what's necessary is a support for creating a session and running it in dockerode. Go implementation for that in terraform was added here - https://github.com/kreuzwerker/terraform-provider-docker/pull/387/files#diff-4596d40531ae2e21f6074d104e6dc7317537946b56d95df847c9209dfbe30fceR329 The session run code is here