apply-templates.sh

#!/usr/bin/env bash
set -Eeuo pipefail

# Don't tolerate outdated bash on Darwin
[ "${BASH_VERSINFO:-0}" -ge 4 ] || (echo "Outdated bash version: ${BASH_VERSION}. If you're on MacOS/Darwin, please 'brew install bash' to move away from this comically outdated version." && exit 1)

[ -f versions.json ] || (echo "run 'versions.sh' first so templates can be applied to the right versions" && exit 1)

type gawk >/dev/null 2>&1 || (echo "Please install the gawk command. On MacOS, run 'brew install gawk'" && exit 1)

# GNU sed for Mac.
# Copied from:
# https://gist.github.com/bittner/5436f3dc011d43ab7551#file-gnu-tools-for-mac-sh
sedcmd="sed"

[[ $(uname) == 'Darwin' ]] && {
	which gsed >/dev/null && {
		sedcmd="gsed"
	} || {
		echo 'ERROR: GNU sed required for Mac. You may use homebrew to install it: brew install gnu-sed'
		exit 1
	}
}

jqt='.jq-template.awk'
if [ -n "${BASHBREW_SCRIPTS:-}" ]; then
	jqt="$BASHBREW_SCRIPTS/jq-template.awk"
elif [ "$BASH_SOURCE" -nt "$jqt" ]; then
	wget -qO "$jqt" 'https://github.com/docker-library/bashbrew/raw/5f0c26381fb7cc78b2d217d58007800bdcfbcfa1/scripts/jq-template.awk'
fi

if [ "$#" -eq 0 ]; then
	versions="$(jq -r 'keys | map(@sh) | join(" ")' versions.json)"
	eval "set -- $versions"
fi

generated_warning() {
	cat <<-EOH
		#
		# NOTE: THIS DOCKERFILE IS GENERATED VIA "apply-templates.sh"
		#
		# PLEASE DO NOT EDIT IT DIRECTLY.
		#

	EOH
}

for version; do
	export version

	variants="$(jq -r '.[env.version].variants | map(@sh) | join(" ")' versions.json)"
	eval "variants=( $variants )"

	for dir in "${variants[@]}"; do
		suite="$(dirname "$dir")"    # "buster", etc
		variant="$(basename "$dir")" # "cli", etc
		export suite variant

		alpineVer="${suite#alpine}" # "3.12", etc
		if [ "$suite" != "$alpineVer" ]; then
			template='Dockerfile-alpine.template'
			from="alpine:$alpineVer"
		else
			template='Dockerfile-debian.template'
			from="debian:$suite-slim"
		fi
		export from

		case "$variant" in
		apache) cmd='["apache2-foreground"]' ;;
		fpm) cmd='["php-fpm"]' ;;
		*) cmd='["php", "-a"]' ;;
		esac
		export cmd

		echo "processing $version/$dir ..."

		variantBlock1="$(if [ -f "Dockerfile-$variant-block-1.template" ]; then gawk -f "$jqt" "Dockerfile-$variant-block-1.template"; fi)"
		variantBlock2="$(if [ -f "Dockerfile-$variant-block-2.template" ]; then gawk -f "$jqt" "Dockerfile-$variant-block-2.template"; fi)"
		export variantBlock1 variantBlock2

		{
			generated_warning
			gawk -f "$jqt" "$template"
		} >"$version/$dir/Dockerfile"

		cp -a \
			docker-php-entrypoint \
			docker-php-ext-* \
			docker-php-source \
			"$version/$dir/"
		if [ "$variant" = 'apache' ]; then
			cp -a apache2-foreground "$version/$dir/"
		fi

		cmd="$(jq <<<"$cmd" -r '.[0]')"
		if [ "$cmd" != 'php' ]; then
			$sedcmd -i -e 's! php ! '"$cmd"' !g' "$version/$dir/docker-php-entrypoint"
		fi
	done
done