share

#!/usr/bin/env python

import os
import pwd
import logging
from subprocess import call, check_output
from argparse import ArgumentParser

DEVNULL = open(os.devnull, 'wb')

def get_username():
    return pwd.getpwuid( os.getuid() )[ 0 ]


def setfacl(path, user, mode, remove=False, recursive=False, default=False):
	if user[0] == ':':
		type = "group"
		name = user[1:]
	else:
		type = "user"
		name = user

	arguments = ['setfacl']

	if default:
		arguments.append("-d")

	if recursive:
		arguments.append('-R')

	if remove:
		acl = "%s:%s" % (type, name)
		action = "-x"
	else:
		acl = "%s:%s:%s" % (type, name, mode)
		action = "-m"
	arguments.append(action)
	arguments.append(acl)
	arguments.append(path)
	print arguments
	call(arguments, stderr=DEVNULL)


def check_executable(path, user):
	print "- make sure all parent paths can be entered by %s" % user
	isfile = os.path.isfile(path)
	if isfile:
		p = os.path.dirname(path)
	else:
		p = path[:]

	while p != "/":
		setfacl(p, user, 'rX')
		p = os.path.dirname(p)


def share(path, users, write, execute, remove, recursive, default=False):
	path = os.path.abspath(path)
	path = os.path.realpath(path)
	print "- share path: ", path

	mode = "r"
	if not os.path.isfile(path):
		mode = mode + "X"
	if write:
		mode = mode + "w"
	
	if execute:
		mode = mode + "x"

	for user in users:
		setfacl(path, user, mode, remove, recursive, default=default)
		if not remove:
			check_executable(path, user)


def getfacl(path, users):
	username = get_username()
	o = check_output(['getfacl', '-p', '-t', path])
	for line in o.splitlines():
		if line.startswith('#'): continue
		e = line.split()
		if len(e) < 3: continue
		role, name, mode = e[:3]
		if name == username: continue
		if users and len(users) > 0:
			ingroups = role.lower() == "group" and ":"+name in users
			inusers = role.lower() == "user" and name in users
			if not ingroups and not inusers:
				continue

		print path, role, name, mode	


def show(path, users):
	path = os.path.abspath(path)
	if os.path.isfile(path):
		getfacl(path, users)
	else:
		for root, dirs, files in os.walk(path):
			getfacl(root, users)
			for file in files:
				getfacl(os.path.join(root,file), users)
		

if __name__ == '__main__':
	parser = ArgumentParser()
	parser.add_argument('-s', '--show', dest='show', action='store_const',
						const=True, default=False,
						help='show shared files and folders')
	parser.add_argument('-w', '--write', dest='write', action='store_const',
						const=True, default=False,
						help='add write access')
	parser.add_argument('-e', '--remove', dest='remove', action='store_const',
						const=True, default=False,
						help='erase/remove access')
	parser.add_argument('-x', '--executable', dest='execute', action='store_const',
						const=True, default=False,
						help='add executavle flag')
	parser.add_argument('-r', '--recursive', dest='recursive', action='store_const',
						const=True, default=False,
						help='apply recursive to all files')
	parser.add_argument('-d', '--default', dest='default', action='store_const',
						const=True, default=False,
						help='apply recursive to all files')
	parser.add_argument('path', help='path to set permission')
	parser.add_argument('users', help='user or groups to give access to, e.g. max or :users',
						nargs='*')

	args = parser.parse_args()
	if isinstance(args.users, basestring):
		args.users = [args.users]

	if args.show:
		show(args.path, args.users)
	else:
		share(args.path, args.users, args.write, args.execute, args.remove, args.recursive, default=args.default)