Update Hashicorp products

hashicorp_update.sh

#!/bin/bash
# array listing requested hashicorp products all lowercase
HASHICORP=(packer terraform vagrant)
DOWNLOAD_URL="https://releases.hashicorp.com"
TMP_DIR="/tmp"
# install products to this directory and create symbolic links to USER_DIR
INSTALL_DIR="/opt/hashicorp"
USER_DIR="/usr/bin"
FILE_EXT="linux_amd64.zip"
# vagrant is packaged differently, currently this script only works with dpkg package manager
OS_VAGRANT_EXT="x86_64.deb"

# compares version numbers from strings
function version_gt() { test "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1"; }

for PRODUCT in "${HASHICORP[@]}"; do
  # check Hashicorp's JSON file for info
  HASHI_VER="$(curl -s https://checkpoint-api.hashicorp.com/v1/check/$PRODUCT | jq -r -M '.current_version' | egrep -o '[0-9].*')"
  if [ -f $USER_DIR/$PRODUCT ]; then
    LOCAL_VER="$($PRODUCT version | head -n 1 | egrep -o '[0-9].*')"
  else 
    LOCAL_VER="0"
  fi
  # create the product directory
  mkdir -p $INSTALL_DIR

  if version_gt $HASHI_VER $LOCAL_VER; then
    echo "time to upgrade: $PRODUCT - local ver: $LOCAL_VER - remote ver: $HASHI_VER"
    # vagrant installs differently
    if [ $PRODUCT = "vagrant" ]; then 
      FILENAME=${PRODUCT}_${HASHI_VER}_${OS_VAGRANT_EXT}
      wget ${DOWNLOAD_URL}/${PRODUCT}/${HASHI_VER}/${FILENAME} -O ${TMP_DIR}/${FILENAME}
      dpkg -i ${TMP_DIR}/${FILENAME}
      vagrant plugin repair
    else # other Hashicorp products are in zip files
      FILENAME=${PRODUCT}_${HASHI_VER}_${FILE_EXT}
      wget ${DOWNLOAD_URL}/${PRODUCT}/${HASHI_VER}/${FILENAME} -O ${TMP_DIR}/${FILENAME}
      unzip -o $TMP_DIR/$FILENAME -d $TMP_DIR
      rm -f $USER_DIR/$PRODUCT 
      mv $TMP_DIR/$PRODUCT $INSTALL_DIR
      ln -s $INSTALL_DIR/$PRODUCT $USER_DIR/$PRODUCT
    fi
    rm -f $TMP_DIR/$FILENAME
   else
    echo "$PRODUCT is up-to-date"
  fi
done