If you're a fan of Ian Bicking's virtualenv library, and you should be, you've probably heard of Doug Hellmann's virtualenvwrapper bash script. Unfortunately for me I have to develop on Windows at work so this does me little good without a Bash shell (it may work under Cygwin, I haven't tried). Thankfully, Python runs everywhere and I was able to hack together a simple virtualenv management script for windows that handles most of my needs.
The script assumes you will store your virtual environments in the directory "C:\virtualenvs" (you can edit this in the script by changing DEFAULT_DIR_PATH), and supports listing, creating, removing and switching virtual environments from cmd.exe. To install, simply save the code below as env.py in your Python scripts folder, typically something like "C:\Python25\Scripts". You can then get a summary of the command line options by typeing "env.py -h" at a command prompt.
Here's the script:
import os
import shutil
from optparse import OptionParser
# default path to store virtualenv directories
# can be modified on a case by case basis with the -d option
DEFAULT_DIR_PATH = "C:\\virtualenvs\\"
def main():
usage = "usage: %prog [options] arg"
parser = OptionParser(usage)
parser.add_option("-r", "--remove", action="store_true", dest="remove",
help="delete the virualenv")
parser.add_option("-c", "--create", action="store_true", dest="create",
help="create the virtualenv if it does not already exist")
parser.add_option("-l", "--list", action="store_true", dest="list",
help="list all current virtualenvs in directory")
parser.add_option("-d", "--directory", dest="directory",
help="path to the directory containing the virtualenv")
(options, args) = parser.parse_args()
dir_path = options.directory
if dir_path is None:
dir_path = DEFAULT_DIR_PATH
# create the virtualenv directory if it does not exist
if not os.path.isdir(dir_path):
os.makedirs(dir_path)
# list virtualenvs and exit
if options.list:
for item in os.listdir(dir_path):
if os.path.isdir(os.path.join(dir_path, item)):
print item
return
# if we are not listing all envs we need a env name
if len(args) != 1:
parser.error("you must supply a virtualenv name")
# store our paths
env_name = args[0]
env_path = os.path.join(dir_path, env_name)
# does this env already exist?
env_exists = os.path.isdir(env_path)
# can't create and remove
if options.create and options.remove:
parser.error('iptions -c and -r are mutually exclusive')
# prompt for confirmation and then delete the virtual env
if options.remove and env_exists:
resp = raw_input('remove directory "%s"? Y/n: ' % env_path)
if resp == 'Y':
print 'removing directory "%s"' % env_path
shutil.rmtree(env_path)
return
# if the env does not exists we either create it (-c) or throw an error
if not env_exists:
if options.create:
print os.system('virtualenv.exe %s' % env_path)
else:
parser.error('virtualenv does not exists. use the -c option to create it.')
# activate the virtualenv
script_path = os.path.join(env_path, 'scripts', 'activate.bat')
os.system('cmd.exe /K "%s"' % script_path)
if __name__ == '__main__':
main()
Here are some usage examples:
# List all environments
> env.py -l
# Switch to a new environment
> env.py myenviron
# Switch to a new environment and
# create it if it doesn't already exist
> env.py -c myenviron
# Remove an environment
> env.py -r myenviron
A couple notes:
- I've only tested this script on Windows XP with Python 2.5. It works for me. Use it at your own risk and all that.
- If you're developing with the Django development server DO NOT exit it using CTRL-BREAK as instructed. This will bork your command process and you'll have to close it out and open a new window. Use CTRL-C instead.
Update:
I've posted this script to Bitbucket where you can check out the latest changes and report any issues you find.
