Simple wrapper script for Python virtualenv

venv.sh

#!/bin/sh

###############################################################################
#
# venv: A simple wrapper for Python virtualenv
#
###############################################################################

VIRTUALENV_ROOT_DIR=~/Projects/Virtualenv

function usage () {
    echo "Usage"
    echo
    echo "  venv Action [env_name]"
    echo
    echo "Action"
    echo
    echo "  usage              - show this usage information"
    echo "  list                 - show all virtual envs"
    echo "  use [env_name]       - set current shell to use a specific env"
    echo "  create [env_name]    - create new Python virtual env"
    echo
}

function list_environments () {
    if [[ -n $VIRTUAL_ENV ]]; then
        current_env=`echo $VIRTUAL_ENV | cut -d "/" -f 6`
    else
        current_env=""
    fi
    
    envs=(`ls $VIRTUALENV_ROOT_DIR`)
    echo
    echo "Virtualenv Pythons"
    echo
    for v in ${envs[@]}; do
        if [[ $v == $current_env ]]; then
            echo "=> $v"
        else
            echo "   $v"
        fi
    done
    echo
}

function switch_environment () {
    env_name=$1
    if [[ -d $VIRTUALENV_ROOT_DIR/$env_name ]]; then
        # Um, not sure how to do this right...
        echo "Run this: source $VIRTUALENV_ROOT_DIR/$env_name/bin/activate"
    else
        echo "Error loading environment: $env_name"
    fi
}

function create_environment () {
    env_name=$1
    if [[ -d $VIRTUALENV_ROOT_DIR/$env_name ]]; then
        echo "Error: $env_name already exists"
    else
        virtualenv --no-site-packages $VIRTUALENV_ROOT_DIR/$env_name
    fi
}

# Main

if [[ $# -eq 1 ]]; then
    if [[ $1 == "list"  ]]; then
        list_environments
    else
        usage
    fi
elif [[ $# -eq 2 ]]; then
    case $1 in
        use )
            switch_environment $2
            ;;
        create )
            create_environment $2
            ;;
        * )
            usage
            ;;
    esac
else
    usage
fi