git-vendor

git-vendor.sh

fatal() {
  echo "$@"
  exit 1
}

get_vendor_dir() {
  [ -n "$VENDOR" ] && echo $VENDOR && return
  [ -d src ] && echo src/vendor && return
  echo vendor
}

main() {
  # go to git top level
  ROOT="`git rev-parse --show-toplevel`"
  [ -z "$ROOT" ] && fatal 'cannot detect git top level'

  # normalize URL, add http:// if it does not have a protocol header
  URL="$1"
  [[ "$URL" != *:* ]] && URL="http://$URL"

  # add git remote on demand
  PACKAGE="`echo $URL | sed 's/^.*://;s#^//*##'`"
  REMOTE=${3:-subtree/$PACKAGE}
  # HACK: auto replace common URLs
  URL=${URL//golang.org\/x/github.com\/golang}
  if ! git remote | grep -q $REMOTE; then 
    # verify git url
    git ls-remote "$URL" &> /dev/null || fatal "$URL is not a git repository"
    git remote add $REMOTE "$URL" || return 1
  fi

  # add --squash flag if needed
  [ ${SQUASH:-0} = 1 ] && GIT_FLAG="$GIT_FLAG --squash"

  pushd $ROOT &>/dev/null

  # add or update subtree to vendor dir
  DIR="$(get_vendor_dir)/$PACKAGE"
  COMMIT=${2:-master}
  if [ -e "$DIR" ]; then
    git subtree pull --prefix $DIR $REMOTE $COMMIT $GIT_FLAG || return 4
  else
    mkdir -p "$(dirname "$DIR")" || return 3
    git subtree add --prefix $DIR $REMOTE $COMMIT $GIT_FLAG || return 4
  fi

  popd &>/dev/null
}

usage() {
  NAME=`basename "$0"`
  cat << !
Easy git-subtree. Clone or update external git repo into a subdirectory.

Usage:

  $NAME GIT-URL [COMMIT]

For example,

  $NAME github.com/jamesgraves/example-go-app
  $NAME http://github.com/jamesgraves/example-go-app master

Options:

  export VENDOR=vendor  # vendor directory, relative to git top level
                        # default: src/vendor if src exists, otherwise vendor
  export SQUASH=1       # 1 or 0. if 1, use --squash to discard history
                        # default: 1 

!
}

if [ -z "$1" ]; then
  usage
else
  main "$@"
fi