build.sh

#!/bin/bash

# This build script will compile libmosquitto_jwt_auth.so for x86_64, aarch64 and armv7l for musl
# dynamic linking targets. This auth module is to be used by mosquitto (musl libc build) like in
# the mosquitto docker containers.
#
# Gotcha: For musl dynamic library targets you need to set RUSTFLAGS="-C target-feature=-crt-static"
#
# David Gräff, 2019

DEST=""
readonly BINFILENAME="libmosquitto_jwt_auth.so"

download() {
    local url="$1"
    local file="$(basename $url)"
    local strip="$3"
    : "${strip:=1}"
    trap "rm $file" EXIT
    ensure wget --no-check-certificate -q --show-progress "$url" -O "$file"
    mkdir -p "$2"
    if [ "$4" = "zip" ]; then
        ensure unzip -q "$file" -d "$2"
    else
        ensure tar xaf "$file" --strip-components=$strip -C "$2"
    fi
    ensure rm "$file"
    trap "" EXIT
}

prerequirements() {
    need_cmd wget
    need_cmd tput
    need_cmd tar

	[ ! -d mosquitto-jwt-auth ] && ensure git clone --depth=1 https://github.com/wiomoc/mosquitto-jwt-auth
	ensure cd mosquitto-jwt-auth
    mkdir -p target/musl
	DEST=$(realpath "target/musl")


    if [ ! -d $DEST/x86_64 ]; then
        say "Download x86_64 musl compiler toolchain"
        download https://musl.cc/x86_64-linux-musl-native.tgz $DEST/x86_64 2
    fi

    if [ ! -d $DEST/armv7l ]; then
        say "Download armv7l musl cross compiler toolchain"
        download https://musl.cc/armv7l-linux-musleabihf-cross.tgz $DEST/armv7l 2
    fi

    if [ ! -d $DEST/aarch64 ]; then
        say "Download aarch64 musl cross compiler toolchain"
        download https://musl.cc/aarch64-linux-musl-cross.tgz $DEST/aarch64 2
    fi
}

compile_crate() {
    local ARCH="$1"
    local TARGET="$ARCH-unknown-linux-$2"
	[ "$ARCH" = "armv7l" ] && TARGET="armv7-unknown-linux-$2"
    local DEST_ARCH="$DEST/$ARCH"
    export PATH=$PATH:$DEST_ARCH/bin
    export PKG_CONFIG_PATH="$DEST_ARCH"
    export PKG_CONFIG_LIBDIR="$DEST_ARCH/lib"
	export RUSTFLAGS="-C target-feature=-crt-static -C linker=$ARCH-linux-$2-gcc"
    say "Build crate for $ARCH"
    ensure cargo build --release --target $TARGET
    local METADATA=$(cargo metadata --format-version 1 | jq -r '.workspace_members[]' | tail -n1)
    CRATE_NAME=$(echo $METADATA | cut -d' ' -f1)
    CRATE_VERSION=$(echo $METADATA | cut -d' ' -f2)
    local BINFILE="target/$TARGET/release/$BINFILENAME"
    say "Before stripping $CRATE_NAME ($CRATE_VERSION): $(wc -c $BINFILE | cut -d' ' -f1) Bytes"
    if [ "$ARCH" = "x86_64" ]; then
        $DEST_ARCH/bin/strip $BINFILE
    else
        local compiler_variant=$(ls $DEST_ARCH/lib/gcc)
        $DEST_ARCH/bin/${compiler_variant}-strip --strip-unneeded $BINFILE
    fi
    say "After stripping: $(wc -c $BINFILE | cut -d' ' -f1) Bytes"

	DOCKER_ARCH="$3"
	MANIFEST="$4"
	DIGEST=$(echo $MANIFEST | jq -r ".manifests[] | select(.platform.architecture == \"$DOCKER_ARCH\") | .digest")

printf "FROM eclipse-mosquitto@$DIGEST
COPY mosquitto-jwt-auth/$BINFILE /
COPY mosquitto.conf /mosquitto/config/mosquitto.conf
ENTRYPOINT [\"/docker-entrypoint.sh\"]
CMD [\"/usr/sbin/mosquitto\" \"-c\" \"/mosquitto/config/mosquitto.conf\"]
ENTRYPOINT [\"/bin\"]
" > ../Dockerfile-$DOCKER_ARCH
}

need_cmd() {
    if ! command -v "$1" > /dev/null 2>&1; then
        err "need '$1' (command not found) $2"
    fi
}

ensure() {
    "$@"
    if [ $? != 0 ]; then
        err "ERROR: command failed: $*";
    fi
}

say() {
	local color=$( tput setaf 2 )
	local normal=$( tput sgr0 )
	echo "${color}$1${normal}"
}

err() {
	local color=$( tput setaf 1 )
	local normal=$( tput sgr0 )
	echo "${color}$1${normal}" >&2
	exit 1
}

prerequirements
export PKG_CONFIG_ALLOW_CROSS=1
export PKG_CONFIG_ALL_STATIC=1

export CC_x86_64_unknown_linux_musl=x86_64-linux-musl-gcc
export CC_armv7_unknown_linux_musleabihf=armv7l-linux-musleabihf-gcc
export LDFLAGS_aarch64_unknown_linux_musl="-lgcc"
export CFLAGS_aarch64_unknown_linux_musl="-lgcc"
export CFLAGS_armv7_unknown_linux_musleabihf="-mfpu=vfpv3-d16"

rustup target add x86_64-unknown-linux-musl
rustup target add armv7-unknown-linux-musleabihf
rustup target add aarch64-unknown-linux-musl

BASE_IMAGE=eclipse-mosquitto
TOKEN=`curl "https://auth.docker.io/token?service=registry.docker.io&scope=repository:library/$BASE_IMAGE:pull" | jq -r .token`
MANIFEST=$(curl  -H "Authorization: Bearer $TOKEN" -H "Accept: application/vnd.docker.distribution.manifest.list.v2+json" https://registry-1.docker.io/v2/library/$BASE_IMAGE/manifests/latest)

compile_crate "x86_64" "musl" "amd64" "$MANIFEST"
compile_crate "aarch64" "musl" "arm64" "$MANIFEST"
compile_crate "armv7l" "musleabihf" "arm" "$MANIFEST"

exit 0