Tool version checker script

check-tool-version.sh

#!/bin/bash

LANGUAGES="erlang elixir nodejs"

get_tool_version() {
  grep "$1" .tool-versions | awk '{print $2}'
}

has_matching_versions() {
  # Usage: has_matching_versions DEPTH VERSION1 VERSION2
  # Usage: has_matching_versions major v1.2.3 v1.2.5   #=> 0 (yes)
  # Usage: has_matching_versions minor v1.2.3 v1.2.5   #=> 0 (yes)
  # Usage: has_matching_versions patch v1.2.3 v1.2.5   #=> 1 (no)
  # Usage: has_matching_versions patch v1.3.0 v1.2.0   #=> 1 (no)
  # Usage: has_matching_versions patch v2.0.0 v1.0.0   #=> 1 (no)

  local CHECK_DEPTH="$1"; shift
  local CURRENT_VERSION="$1"; shift
  local NEEDED_VERSION="$1"; shift
  local CURRENT_MAJOR
  local CURRENT_MINOR
  local CURRENT_PATCH
  local NEEDED_MAJOR
  local NEEDED_MINOR
  local NEEDED_PATCH

  CURRENT_MAJOR=$(echo "${CURRENT_VERSION#v}" | cut -d. -f1)
  CURRENT_MINOR=$(echo "$CURRENT_VERSION" | cut -d. -f2)
  CURRENT_PATCH=$(echo "$CURRENT_VERSION" | cut -d. -f3)

  NEEDED_MAJOR=$(echo "${NEEDED_VERSION#v}" | cut -d. -f1)
  NEEDED_MINOR=$(echo "$NEEDED_VERSION" | cut -d. -f2)
  NEEDED_PATCH=$(echo "$NEEDED_VERSION" | cut -d. -f3)

  local RETURN
  if [ "$CURRENT_MAJOR" = "$NEEDED_MAJOR" ]; then RETURN=0; else RETURN=1; fi
  if [ "$RETURN" = 1 ]; then return 1; fi
  if [ "$CHECK_DEPTH" = "minor" ]; then
    if [ "$CURRENT_MINOR" = "$NEEDED_MINOR" ]; then RETURN=0; else RETURN=1; fi
  fi
  if [ "$RETURN" = 1 ]; then return 1; fi
  if [ "$CHECK_DEPTH" = "patch" ]; then
    if [ "$CURRENT_PATCH" = "$NEEDED_PATCH" ]; then RETURN=0; else RETURN=1; fi
  fi
  return $RETURN
}

should_check_language () {
  if [[ "$LANGUAGES_TO_CHECK" = *$1* ]]; then return 0; else return 1; fi
}

if [ "$#" -eq 0 ]; then
  LANGUAGES_TO_CHECK=$LANGUAGES
else
  LANGUAGES_TO_CHECK=$*
fi

# Erlang
if should_check_language "erlang"; then
  if command -v erl >/dev/null; then
    NEEDED_ERLANG_VERSION="$(get_tool_version "erlang")"
    CURRENT_ERLANG_VERSION=$(
      erl -eval '{ok, Version} = file:read_file(filename:join([code:root_dir(), "releases", erlang:system_info(otp_release), "OTP_VERSION"])), io:fwrite(Version), halt().' -noshell
    )
    if has_matching_versions major "$CURRENT_ERLANG_VERSION" "$NEEDED_ERLANG_VERSION"; then
      echo "Erlang/OTP major versions match"
      echo "Requested: $NEEDED_ERLANG_VERSION. Available: $CURRENT_ERLANG_VERSION"
    else
      echo "The Erlang version does not match"
      echo "Requested: $NEEDED_ERLANG_VERSION. Available: $CURRENT_ERLANG_VERSION"
      exit 1
    fi
  else
    echo "Erlang is not installed"
    exit 1
  fi
fi

# Elixir
if should_check_language "elixir"; then
  if command -v elixir >/dev/null; then
    NEEDED_ELIXIR_VERSION="$(get_tool_version "elixir" | sed 's/-otp.*//')"
    NEEDED_ELIXIR_OTP_VERSION="$(get_tool_version "elixir" | cut -d- -f3)"
    CURRENT_ELIXIR_VERSION="$(elixir --version | tail -n 1 | awk '{print $2}')"
    CURRENT_ELIXIR_OTP_VERSION="$(elixir --version | tail -n 1 | awk '{print $6}' | grep -o '[0-9]*')"
    if has_matching_versions patch "$CURRENT_ELIXIR_VERSION" "$NEEDED_ELIXIR_VERSION"; then
      echo "Elixir versions match"
      echo "Requested: $NEEDED_ELIXIR_VERSION. Available: $CURRENT_ELIXIR_VERSION"
    else
      echo "The Elixir version does not match"
      echo "Requested: $NEEDED_ELIXIR_VERSION. Available: $CURRENT_ELIXIR_VERSION"
      exit 1
    fi

    if has_matching_versions major "$CURRENT_ELIXIR_OTP_VERSION" "$NEEDED_ELIXIR_OTP_VERSION"; then
      echo "Elixir OTP versions match"
      echo "Requested: $NEEDED_ELIXIR_OTP_VERSION. Available: $CURRENT_ELIXIR_OTP_VERSION"
    else
      echo "The Elixir OTP version does not match"
      echo "Requested: $NEEDED_ELIXIR_OTP_VERSION. Available: $CURRENT_ELIXIR_OTP_VERSION"
      exit 1
    fi
  else
    echo "Elixir is not installed"
    exit 1
  fi
fi

# NodeJS
if should_check_language "nodejs"; then
  if command -v node >/dev/null; then
    NEEDED_NODEJS_VERSION="$(get_tool_version "nodejs")"
    CURRENT_NODEJS_VERSION="$(node --version)"
    if has_matching_versions major "$CURRENT_NODEJS_VERSION" "$NEEDED_NODEJS_VERSION"; then
      echo "NodeJS major versions match"
      echo "Requested: $NEEDED_NODEJS_VERSION. Available: $CURRENT_NODEJS_VERSION"
    else
      echo "The NodeJS version does not match"
      echo "Requested: $NEEDED_NODEJS_VERSION. Available: $CURRENT_NODEJS_VERSION"
      exit 1
    fi
  else
    echo "NodeJS is not installed"
    exit 1
  fi
fi