install-binary.sh

#!/usr/bin/env bash

# Shamelessly copied from https://github.com/technosophos/helm-template

PROJECT_NAME="helm-update-config"
PROJECT_GH="bluebosh/${PROJECT_NAME}"

: "${HELM_PLUGIN_DIR:=\"$(helm home --debug=false)/plugins/helm-update-config\"}"

# Convert the HELM_PLUGIN_DIR to unix if cygpath is
# available. This is the case when using MSYS2 or Cygwin
# on Windows where helm returns a Windows path but we
# need a Unix path

if type cygpath > /dev/null 2>&1; then
  HELM_PLUGIN_DIR=$(cygpath -u "${HELM_PLUGIN_DIR}")
fi

if [[ $SKIP_BIN_INSTALL == "1" ]]; then
  echo "Skipping binary install"
  exit
fi

# initArch discovers the architecture for this system.
initArch() {
  ARCH=$(uname -m)
  case $ARCH in
    armv5*) ARCH="armv5";;
    armv6*) ARCH="armv6";;
    armv7*) ARCH="armv7";;
    aarch64) ARCH="arm64";;
    x86) ARCH="386";;
    x86_64) ARCH="amd64";;
    i686) ARCH="386";;
    i386) ARCH="386";;
  esac
}

# initOS discovers the operating system for this system.
initOS() {
  OS=$(uname | tr '[:upper:]' '[:lower:]')
}

# verifySupported checks that the os/arch combination is supported for
# binary builds.
verifySupported() {
  local supported="linux-amd64\nfreebsd-amd64\nmacos-amd64\nwindows-amd64\ndarwin-amd64"
  if ! echo "${supported}" | grep -q "${OS}-${ARCH}"; then
    echo "No prebuild binary for ${OS}-${ARCH}."
    exit 1
  fi

  if ! type "curl" > /dev/null && ! type "wget" > /dev/null; then
    echo "Either curl or wget is required"
    exit 1
  fi
}

# getDownloadURL checks the latest available version.
getDownloadURL() {
  local version
  version=$(git -C "$HELM_PLUGIN_DIR" describe --tags --exact-match 2>/dev/null || true)
  if [ -n "$version" ]; then
    DOWNLOAD_URL="https://github.com/${PROJECT_GH}/releases/download/${version}/helm-update-config_${OS}_${ARCH}"
  else
    # Use the GitHub API to find the download url for this project.
    local url="https://api.github.com/repos/$PROJECT_GH/releases/latest"
    if type "curl" > /dev/null; then
      DOWNLOAD_URL=$(curl -s $url | grep $OS | awk '/\"browser_download_url\":/{gsub( /[,\"]/,"", $2); print $2}')
    elif type "wget" > /dev/null; then
      DOWNLOAD_URL=$(wget -q -O - $url | grep $OS | awk '/\"browser_download_url\":/{gsub( /[,\"]/,"", $2); print $2}')
    fi
  fi
}

# downloadFile downloads the latest binary package and also the checksum
# for that binary.
downloadFile() {
  PLUGIN_TMP_FILE="/tmp/${PROJECT_NAME}"
  echo "Downloading $DOWNLOAD_URL"
  if type "curl" > /dev/null; then
    curl -L "$DOWNLOAD_URL" -o "$PLUGIN_TMP_FILE" > /dev/null
  elif type "wget" > /dev/null; then
    wget -q -O "$PLUGIN_TMP_FILE" "$DOWNLOAD_URL" > /dev/null
  fi
}

# installFile verifies the SHA256 for the file, then unpacks and
# installs it.
installFile() {
  HELM_TMP_BIN="/tmp/$PROJECT_NAME"
  chmod +x "${HELM_TMP_BIN}"
  echo "Preparing to install into ${HELM_PLUGIN_DIR}"
  mkdir -p "$HELM_PLUGIN_DIR/bin"
  mv "$HELM_TMP_BIN" "$HELM_PLUGIN_DIR/bin/"
}

# fail_trap is executed if an error occurs.
fail_trap() {
  result=$?
  if [ "$result" != "0" ]; then
    echo "Failed to install ${PROJECT_NAME}"
    printf "\tFor support, go to https://github.com/bluebosh/helm-update-config"
  fi
  exit $result
}

# testVersion tests the installed client to make sure it is working.
testVersion() {
  set +e
  echo "$PROJECT_NAME installed into $HELM_PLUGIN_DIR/$PROJECT_NAME"
  "${HELM_PLUGIN_DIR}/bin/helm-update-config" -h
  set -e
}

# Execution

#Stop execution on any error
trap "fail_trap" EXIT
set -e
initArch
initOS
verifySupported
getDownloadURL
downloadFile
installFile
testVersion