dockertest does not support buildkit

[pjh]

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Ory Network Project

No response

Describe the bug

Dockertest does not yet support BuildKit (docker buildx) for building images from a Dockerfile. For example, when I try to use dockertest to build my backend server for testing I get this failure:

$ go test -C integration/
failed to build and run backend container: the --mount option requires BuildKit. Refer to https://docs.docker.com/go/buildkit/ to learn how to build images with BuildKit enabled

BuildKit is widely used for building docker images. #416 was proposed over a year ago but it has not yet been merged. Could that change plus whatever other support is needed be prioritized?

Reproducing the bug

1. Write a Dockerfile with a step that attempts to mount a file. For example:
   RUN --mount=type=secret,id=netrc_file go build ...
2. Attempt to build the image using one of dockertest's build methods, such as:
   container, err := pool.BuildAndRunWithOptions("path/to/Dockerfile", runOpts, hostConfigModifier)

Relevant log output

No response

Relevant configuration

No response

Version

github.com/ory/dockertest/v3 v3.10.0

On which operating system are you observing this issue?

None

In which environment are you deploying?

None

Additional Context

No response

[TristanSpeakEasy]

Have run into this issue myself today

I have forked the repo and attempted a fix which works. Basically a query param called version with value set to 2 for BuildKit support needs to be passed to the /build command when building the image.

I could open a PR to address this, but the question is should the version be configurable? Or can we just hard code it to 2 as I don't think there is too much reason not to use BuildKit