How to use a base_image with multiple-platforms for aarch64?

[laoshanxi]

I am trying this to run arm64 docker container, but seems I can not get a QMENU ARM64 environment, still X86 runner, is there anything wrong with my configuration?

action output:
https://github.com/laoshanxi/app-mesh/actions/runs/4329800139/jobs/7560595971

workflow:

      - name: build with ubuntu18 ARM64
        uses: uraimo/run-on-arch-action@v2.5.0
        with:
          arch: aarch64
          distro: ubuntu_latest
          githubToken: ${{ github.token }}
          dockerRunArgs: |
            --volume ${{ github.workspace }}:/workspace --workdir /workspace
          base_image: laoshanxi/appmesh:build_ubuntu18
          shell: /bin/sh
          run: |
            mkdir ubuntu18arm
            cd ubuntu18arm
            cmake ..
            make -j4
            make pack
            ls
            make test ARGS='-V'

and also I founc $(arch) return x86_64.

BTW, the base_image laoshanxi/appmesh:build_ubuntu18 here have arm64 and x86_64 platforms, so how can I force specify arm64 to run this base image?

[uraimo]

Hi, yes, the problem is that the image is multi-platform and the action doesn't allow to explicitly specify the architecture. Adding support for --platform could be useful also for images that don't specify the architecture, but in this release I don't plan to add any more parameters.

AFAIK, you could select a specific version of the image adding the digest like <username>/<image>:latest@sha256:<digest> but since the digest changes you'll need to retrieve it with docker inspect every time and pass it to the run-on-arch job. It seems like it should work but I'm not sure if it's doable.

[laoshanxi]

Will we plan support apply parameter arch: aarch64 when specified base_image ?

I saw from README, mentioned.

base_image: Specify a custom base image, such as [busybox](https://hub.docker.com/_/busybox), arch and distro should be set to none in this case.

#103 (comment)

[uraimo]

Yes, I will give a better name to the parameters but that's the idea, if you don't use the default images you can optionally specify a platform for the base_image.

[grimbough]

I think you can do this by just specifying --platform=linux/arm64 as part of the base_image argument e.g.

base_image: --platform=linux/arm64 bioconductor/bioconductor_docker:RELEASE_3_16

That seems to work for me e.g. https://github.com/grimbough/arm64-workflow/actions/runs/4568897053/jobs/8064509304#step:3:112

[laoshanxi]

Thanks, I found this way also works:
https://github.com/laoshanxi/app-mesh/blob/main/.github/workflows/publish-github-release.yml#L59