Docker build squash

[fabiosanger]

I would like to enable squash during build, but none of the workarounds available seem to do the trick, below is the current build and dockerfile, with following error

"Step #1 - "build": "--squash" is only supported on a Docker daemon with experimental features enabled"

#syntax=docker/dockerfile:1.5.2
FROM jupyter/r-notebook:ubuntu-20.04

steps:
  - id: 'pull-experimental'
    name: 'gcr.io/cloud-builders/docker'
    args: [ 'pull', 'docker/dockerfile:1.5.2' ]
    env:
      - DOCKER_BUILDKIT=1
    # build the container image
  - id: 'build'
    waitFor: ['pull-experimental']
    name: 'gcr.io/cloud-builders/docker'
    entrypoint: 'bash'
    args:
      ['-c', 'docker build --squash --memory-swap=-1 -t eu.gcr.io/$PROJECT_ID/${_IMAGE_TAG} -f ${_IMAGE_NAME}/Dockerfile .']
    env:
      - DOCKER_BUILDKIT=1

[matthewrobertson]

The image you are pulling your pull-experimental is not being used in your build step. If you are trying to use it as the builder, you would need to set it as the step name:

  - id: 'build'
    waitFor: ['pull-experimental']
    name: docker/dockerfile:1.5.2'
    # ...

By the way, if you are only trying to flatten the jupyter/r-notebook:ubuntu-20.04 and copy it into your own AR repo, it might be easier to use Crane flatten