build.sh

#!/bin/bash

set -e

SRC=$(realpath $(cd -P "$(dirname "${BASH_SOURCE[0]}")" && pwd))

NAME=$(basename $SRC)
VER=
STATIC=0
FORCE=0
CHECK=1
INSTALL=0
BUILDONLY=0
VERBOSE=false
CGO_ENABLED=1
LDNAME=main.name
LDVERSION=main.version
PLATFORM=$(go env GOOS)
ARCH=$(go env GOARCH)
GOARCH=$ARCH

TAGS=(
)

latest_tag() {
  # get latest tag version
  pushd $SRC &> /dev/null
  git tag -l|grep -E '^v[0-9]+\.[0-9]+\.[0-9]+(\.[0-9]+)?$'|sort -r -V|head -1||:
  popd &> /dev/null
}

OPTIND=1
while getopts "a:v:sfnibxt:r" opt; do
case "$opt" in
  a) ARCH=$OPTARG ;;
  v) VER=$OPTARG ;;
  s) STATIC=1 ;;
  f) FORCE=1 ;;
  n) CHECK=0 ;;
  i) INSTALL=1 ;;
  b) BUILDONLY=1 ;;
  x) VERBOSE=true ;;
  t) TAGS=($OPTARG) ;;
  r) VER=$(latest_tag) ;;
esac
done

# neither -v or -r specified, or -v=master, set FORCE and VER
if [[ "$VER" = "" || "$VER" == "master" ]]; then
  VER=0.0.0-dev
  FORCE=1
fi

VER="${VER#v}"

BUILD=$SRC/build
DIR=$BUILD/$PLATFORM/$ARCH/$VER

TAR=tar
EXT=tar.bz2
BIN=$DIR/$NAME

case $PLATFORM in
  windows)
    EXT=zip
    BIN=$BIN.exe
  ;;
  darwin)
    TAR=gtar
  ;;
esac
OUT=$DIR/$NAME-$VER-$PLATFORM-$ARCH.$EXT

CARCH=
QEMUARCH=
GNUTYPE=
CC=
CXX=
EXTLD=g++

if [[ "$PLATFORM" == "linux" && "$ARCH" != "$GOARCH" ]]; then
  case $ARCH in
    arm)   CARCH=armhf   QEMUARCH=arm     GNUTYPE=gnueabihf ;;
    arm64) CARCH=aarch64 QEMUARCH=aarch64 GNUTYPE=gnu ;;
    *)
      echo "error: unknown arch $ARCH"
      exit 1
    ;;
  esac
  LDARCH=$CARCH
  if [[ "$ARCH" == "arm" ]]; then
    if [ -d /usr/arm-linux-$GNUTYPE ]; then
      LDARCH=arm
    elif [ -d /usr/arm-none-linux-$GNUTYPE ]; then
      LDARCH=arm-none
    fi
  fi
  CC=$LDARCH-linux-$GNUTYPE-gcc
  CXX=$LDARCH-linux-$GNUTYPE-c++
  EXTLD=$LDARCH-linux-$GNUTYPE-g++
fi

LDFLAGS=(
  -s
  -w
  -X $LDNAME=$NAME
  -X $LDVERSION=$VER
)

if [ "$STATIC" = "1" ]; then
  OUT=$DIR/${NAME}_static-$VER-$PLATFORM-$ARCH.$EXT
  BIN=$DIR/${NAME}_static
  case $PLATFORM in
    linux)
      TAGS+=(
        netgo
        osusergo
      )
      EXTLDFLAGS=(
        -static
        -lm
        -ldl
      )
      EXTLDFLAGS="${EXTLDFLAGS[@]}"
      LDFLAGS+=(
        -linkmode=external
        -extldflags \'$EXTLDFLAGS\'
        -extld $EXTLD
      )
    ;;
    *)
      echo "ERROR: fully static builds not currently supported for $PLATFORM/$ARCH"
      exit 1
    ;;
  esac
fi

# check not overwriting existing build artifacts
if [[ -e $OUT && "$FORCE" != "1" && "$INSTALL" == "0" ]]; then
  echo "ERROR: $OUT exists and FORCE != 1 (try $0 -f)"
  exit 1
fi

TAGS="${TAGS[@]}"
LDFLAGS="${LDFLAGS[@]}"

echo "APP:         $NAME/${VER} ($PLATFORM/$ARCH)"
if [ "$STATIC" = "1" ]; then
  echo "STATIC:      yes"
fi
echo "BUILD TAGS:  $TAGS"
echo "LDFLAGS:     $LDFLAGS"

pushd $SRC &> /dev/null

if [ -f $OUT ]; then
  echo "REMOVING:    $OUT"
  rm -rf $OUT
fi
mkdir -p $DIR
echo "BUILDING:    $BIN"

# build
echo "BUILD:"

VERB=build
OUTPUT="-o $BIN"
if [ "$INSTALL" = "1" ]; then
  VERB=install OUTPUT=""
elif [ "$BUILDONLY" = "1" ]; then
  OUTPUT=""
fi
(set -x;
  CC=$CC \
  CXX=$CXX \
  CGO_ENABLED=$CGO_ENABLED \
  GOARCH=$ARCH \
  go $VERB \
    -v=$VERBOSE \
    -x=$VERBOSE \
    -ldflags="$LDFLAGS" \
    -tags="$TAGS" \
    -trimpath \
    $OUTPUT
)

if [[ "$INSTALL" == "1" || "$BUILDONLY" == "1" ]]; then
  exit
fi

(set -x;
  file $BIN
)
if [[ "$PLATFORM" != "windows" ]]; then
  (set -x;
    chmod +x $BIN
  )
fi

# purge disk cache
if [[ "$PLATFORM" == "darwin" && "$CI" == "true" ]]; then
  (set -x;
    sudo /usr/sbin/purge
  )
fi

built_ver() {
  if [[ "$PLATFORM" == "linux" && "$ARCH" != "$GOARCH" ]]; then
    EXTRA=
    if [ -d /usr/$LDARCH-linux-$GNUTYPE/libc ]; then
      EXTRA="-L /usr/$LDARCH-linux-$GNUTYPE/libc"
    fi
    qemu-$QEMUARCH \
      -L /usr/$LDARCH-linux-$GNUTYPE \
      $EXTRA \
      $BIN --version
  elif [[ "$PLATFORM" == "darwin" && "$ARCH" != "$GOARCH" ]]; then
    echo "$NAME ${VER#v}"
  else
    $BIN --version
  fi
}

# check build
if [[ "$CHECK" == "1" ]]; then
  BUILT_VER=$(built_ver)
  if [ "$BUILT_VER" != "$NAME ${VER#v}" ]; then
    echo -e "\n\nERROR: expected $NAME --version to report '$NAME ${VER#v}', got: '$BUILT_VER'"
    exit 1
  fi
  echo "REPORTED:    $BUILT_VER"
fi

# pack
cp $SRC/LICENSE $DIR
case $EXT in
  tar.bz2) $TAR -C $DIR -cjf $OUT $(basename $BIN) LICENSE ;;
  zip) zip $OUT -j $BIN LICENSE ;;
esac

# report
echo "PACKED:      $OUT ($(du -sh $OUT|awk '{print $1}'))"

case $EXT in
  tar.bz2) (set -x; $TAR  -jvtf $OUT) ;;
  zip)     (set -x; unzip -l    $OUT) ;;
esac

(set -x;
  sha256sum $DIR/*
)

popd &> /dev/null