Set a multi platform Docker Images build in CI

#!/bin/sh
# This script demonstrates how to use `docker buildx` to build container
# images for the linux/amd64 and linux/arm64 platforms.  It creates a
# `docker buildx` builder instance when required.
#
# If you change the platforms, be sure to
#
#  (1) delete the buildx builder named `skaffold-builder`, and
#  (2) update the corresponding node-affinities in k8s/pod.yaml.

# The platforms to build. Default to linux/amd64.
PLATFORMS=${PLATFORMS:=linux/amd64}

# `buildx` uses named _builder_ instances configured for specific platforms.
# This script creates a `skaffold-builder` as required.
if ! docker buildx inspect skaffold-builder >/dev/null 2>&1; then
  docker buildx create --bootstrap\
      --name skaffold-builder\
      --driver=kubernetes\
      '--driver-opt="namespace=platform-staging","qemu.install=true","tolerations=key=team,value=platform"'\
      --platform $PLATFORMS
fi

# Building for multiple platforms requires pushing to a registry
# as the Docker Daemon cannot load multi-platform images. 
if [ "$PUSH_IMAGE" = true ]; then
  args="--platform $PLATFORMS --push"
else
  args="--load"
fi

set -x      # show the command-line
docker buildx build --builder skaffold-builder --tag $IMAGE $args "$BUILD_CONTEXT"

apiVersion: skaffold/v2beta29
kind: Config
build:
  tagPolicy:
    envTemplate:
      template: "{{.VERSION}}"
  artifacts:
    - image: "$DOCKER_REGISTRY/nuxeo/builder-base-rockylinux9"
      platforms:
        - "linux/amd64"
        - "linux/arm64"
      context: rockylinux9
      custom:
        buildCommand: sh buildx.sh