[REQ] Support inputting tarballs

[audunsolemdal]

What kind of request is this?

New feature

What is your request or suggestion?

I am building container tarballs in my Github Actions workflows so that they can be uploaded to a self-hosted Github runner with network access to my container registry.

I would like to support inputting tarball files directly to copa, and have it import the tarball to a container image if need be.
From my understanding #604 will support outputting tarball files, but copa will still require a loaded container image to run commands against.

    - name: Build docker image using cache
      uses: docker/build-push-action@v5
      id: build
      with:
        context: ${{ inputs.build-path }}
        file: ${{ inputs.dockerfile-path }}
        build-args: ${{ inputs.build-arg }}
        load: false
        push: false
        tags: ${{ steps.meta.outputs.tags }}
        labels: ${{ steps.meta.outputs.labels }}
        cache-from: type=gha
        outputs: type=docker,dest=./image.tar

      - name: Run Trivy vulnerability scanner for OS vulerabilities
        if: "${{ inputs.run-image-scan == 'true' && steps.build.outputs.cache-hit != 'true'}}"
        uses: aquasecurity/[email protected]
        with:
          input: ./image.tar
          format: "json"
          output: "report.json"
          severity: ${{inputs.image-scan-severity}}
          ignore-unfixed: true
          scanners: "vuln"
          vuln-type: "os"

       (..)
      - name: Run Copa action 
        if: steps.vuln_count.outputs.vuln_count != '0' 
        id: copa 
        uses: project-copacetic/copa-action@v1 
        with: 
          input-file: image.tar
          output-file: image-patched.tar

    - name: Put image in GHA cache
      id: cache
      uses: actions/cache@v4
      with:
        key: ${{ inputs.artifact }}
        path: ./image-patched.tar

Are you willing to submit PRs to contribute to this feature request?

• Yes, I am willing to implement it.

[ashnamehrotra]

@MiahaCybersec this can be another good issue to work on. One way to do this can be extracting the manifest.json file from the tar to get the image name from RepoTags before calling InitializeBuildkitConfig.