Script for selecting and calling the correct Grails version when you have more than one version installed

grails

#!/bin/sh
# Author: Deluan (http://techbeats.deluan.com)

# Check if GRAILS_HOME is set
if [ -z "$GRAILS_HOME" -o ! -d "$GRAILS_HOME" ]; then
	echo "Error: GRAILS_HOME not set"
	exit 2
fi

# Extract the base path from GRAILS_HOME
BASE_GRAILS_PATH=`echo $GRAILS_HOME | sed -e "s/[^\/\\]*$//" -e "s/^$/./"`
APP_PROP="application.properties"

# Try to get the version from the command line
TRY_VERSION=$1
if [ -d "${BASE_GRAILS_PATH}/grails-${TRY_VERSION}" ]; then
	VERSION=$TRY_VERSION
	shift
fi 

# Or else get the version from the application.properties in the current directory
[ -z "$VERSION" -a -f "$APP_PROP" ] &&
    VERSION=`awk -F'=' '/app.grails.version/ { print $2 }' $APP_PROP | tr -d '\r\n'`

# Or else use the default version
if [ -z "$VERSION" ]; then  
    VERSION=`basename $GRAILS_HOME | cut -f 2 -d "-"`
fi

export GRAILS_HOME=${BASE_GRAILS_PATH}/grails-${VERSION}
GRAILS_CMD=${GRAILS_HOME}/bin/grails

if [ ! -x "$GRAILS_CMD" ]; then
	echo "Error: grails command not found at '$GRAILS_CMD'!"
	exit 3
fi

exec $GRAILS_CMD $*

Prerequisites

• All your Grails versions must be installed under the same base directory. Ex:

  /opt/grails-1.0.3
  /opt/grails-1.1.1
  /opt/grails-1.3.3
  /opt/grails-1.3.5-SNAPSHOT
  

• GRAILS_HOME environment variable must be set and point to your "default" Grails installation

• This script was tested on Mac OS X (Snow Leopard), Linux (Ubuntu) and Windows (with cygwin)

Installation

• Download the script: http://gist.github.com/601039
• Include the folder where it is installed in your PATH.
• Exclude $GRAILS_HOME/bin from your PATH

Usage

Using the script is as transparent as possible:

• If you invoke it from a project folder, it will detect the version used by the project and call the correct grails (if it is installed in your system)

• If you invoke it from any other folder that does not contain a Grails project, it will call the "default" Grails installation

• If you want to call a specific Grails version (i.e. when doing an upgrade) you can specify the version you want in the first parameter. Ex:

  $ grails 1.3.3 upgrade