Action v6 using --cache-from isn't compatible with latest docker buildx 0.20.0

[farvour]

Contributing guidelines

• I've read the contributing guidelines and wholeheartedly agree

I've found a bug, and:

• The documentation does not mention anything about my problem
• There are no open or closed issues that are related to my problem

Description

When trying to use this Action @v6 with the latest Docker Buildx 0.20.0, the --cache-from directive causes an error.

We are using a CSV list of values for cache-from which appear to get squashed together on a single --cache-from CSV. Whereas, the tag values are separated into separate --tag.

Expected behaviour

Buildx action builds with arguments properly.

Actual behaviour

Error: buildx failed with: ERROR: invalid value <REDACTED>.dkr.ecr.us-gov-west-1.amazonaws.com/app:git-000

Repository URL

No response

Workflow run URL

No response

YAML workflow

- name: Build, tag and push image to ECR - stage1
        uses: docker/build-push-action@v6
        with:
          context: "${{ steps.app-dockerfile-selector.outputs.context }}"
          file: "${{ steps.app-dockerfile-selector.outputs.dockerfile }}"
          target: stage1
          push: true
          tags: "${{ steps.docker-set-build-tags.outputs.tags }}" # < CSV list
          platforms: "${{ steps.docker-set-build-vals.outputs.platform }}"
          build-args: |
            BUILDKIT_INLINE_CACHE=1
            BUILD_GIT_SHA=${{ needs.prebuild.outputs.head-ref-short-sha }}
          cache-from: "${{ steps.docker-set-build-tags-cache-from.outputs.tags }}" # < CSV list

Workflow logs

No response

BuildKit logs

Additional info

Is it related to this? #2814

[crazy-max]

Is it related to this? #2814

This might be related but without logs it's hard to figure out. Can you post the full logs of the Build, tag and push image to ECR - stage1 step please?

We are using a CSV list of values for cache-from which appear to get squashed together on a single --cache-from CSV

Fyi multiple cache-from entries for this input only supports the list format: https://github.com/docker/build-push-action?tab=readme-ov-file#inputs

Such as:

  cache-from: |
    type=registry,...
    type=gha,...

[crazy-max]

Added tests in docker/build-push-action#1307 and can't repro. If you have a link to a repository with small repro or workflow logs that would help. Closing in the meantime.

[crazy-max]

After discussing internally this looks like an actual regression in Buildx 0.20.0, cache-from = "ref1,ref2" is a valid pattern.

[crazy-max]

fixed in #2944