build-multiarch.sh

#!/bin/bash

# grab global variables
source vars

DOCKER=$(which docker)
BUILD_INST=${CONTAINER_NAME}"-builder"
BUILD_DATE=$(date -u '+%Y-%m-%dT%H:%M:%S%z')

# MODE options:
#  - dry_run: (default) build images, but DO NOT push to dockerhub
#  - go_time: build and push all images
MODE="DRY_RUN"

if [ "$#" -gt 0 ]; then
  # argument supplied. check if it's "go time"
  if [ "$1" == "--go-time" ]; then
    MODE="GO_TIME"
  fi
fi


## requirements:
# - docker buildx plugin (https://docs.docker.com/buildx/working-with-buildx/)
if [ ! -f ~/.docker/cli-plugins/docker-buildx ]; then
  echo "[ERROR] docker buildx plugin not found!"
  echo "        => https://github.com/docker/buildx/"
  exit 1

else
  # check if build instance (BUILD_INST) is present
  BUILDER_CHECK=$($DOCKER buildx ls| grep ${BUILD_INST})
  if [ ! -n "$BUILDER_CHECK" ]; then
    # not found. let's create it
    $DOCKER run --rm --privileged multiarch/qemu-user-static --reset -p yes
    $DOCKER buildx create --name ${BUILD_INST} --driver docker-container --use
  fi

  # finally, let's build the ntp container
  $DOCKER buildx use ${BUILD_INST}

  # check for dry run. if true, build but do not push image to registry
  if [ "${MODE}" == "DRY_RUN" ]; then
    $DOCKER buildx build --platform linux/amd64,linux/arm64,linux/ppc64le,linux/s390x,linux/386,linux/arm/v7,linux/arm/v6 \
                         --build-arg BUILD_DATE=${BUILD_DATE}                                                             \
                         --tag ${IMAGE_NAME} .
    echo "!! DRY RUN ONLY. NO IMAGE PUSHED TO REGISTRY !!"

  else
    $DOCKER buildx build --platform linux/amd64,linux/arm64,linux/ppc64le,linux/s390x,linux/386,linux/arm/v7,linux/arm/v6 \
                         --build-arg BUILD_DATE=${BUILD_DATE}                                                             \
                         --tag ${IMAGE_NAME}                                                                              \
                         --push .
  fi

  # clean up build artifacts
  $DOCKER rm -f $($DOCKER ps --filter "name=buildx_buildkit" --format "{{.ID}}")
fi