ansible/group

#!/usr/bin/env python

# (c) 2012, Stephen Fromm <sfromm@gmail.com>
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.

try:
    import json
except ImportError:
    import simplejson as json
import os
import grp
import shlex
import subprocess
import sys

GROUPADD = "/usr/sbin/groupadd"
GROUPDEL = "/usr/sbin/groupdel"
GROUPMOD = "/usr/sbin/groupmod"
GPASSWD  = "/usr/bin/gpasswd"

def debug(msg):
    # ansible ignores stderr, so it's safe to use for debug
    print >>sys.stderr, msg
    #pass

def exit_json(rc=0, **kwargs):
    if 'name' in kwargs:
        debug("add group info to exit_json")
        add_group_info(kwargs)
    print json.dumps(kwargs)
    sys.exit(rc)

def fail_json(**kwargs):
    kwargs['failed'] = True
    exit_json(rc=1, **kwargs)

def add_group_info(kwargs):
    name = kwargs['name']
    if group_exists(name):
        kwargs['state'] = 'present'
        info = group_info(name)
        kwargs['gid'] = info[2]
        kwargs['members'] = info[3]
    else:
        kwargs['state'] = 'absent'
    return kwargs

def group_del(group):
    cmd = [GROUPDEL, group]
    debug("Arguments to groupdel: %s" % (" ".join(cmd)))
    rc = subprocess.call(cmd, shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    if rc == 0:
        return True
    else:
        return False

def group_add(group, **kwargs):
    cmd = [GROUPADD]
    for key in kwargs:
        if key == 'gid' and kwargs[key] is not None:
            cmd.append('-g')
            cmd.append(kwargs[key])
    cmd.append(group)
    debug("Arguments to groupadd: %s" % (" ".join(cmd)))
    rc = subprocess.call(cmd, shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    if rc == 0:
        return True
    else:
        return False

def group_mod(group, **kwargs):
    cmd = [GROUPMOD]
    info = group_info(group)
    for key in kwargs:
        if key == 'gid':
            if kwargs[key] is not None and info[2] != int(kwargs[key]):
                cmd.append('-g')
                cmd.append(kwargs[key])
    if len(cmd) == 1:
        return False
    cmd.append(group)
    debug("Arguments to groupmod: %s" % (" ".join(cmd)))
    rc = subprocess.call(cmd, shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    if rc == 0:
        return True
    else:
        return False

def group_has_member(group, member):
    if not group_exists(group):
        return False
    info = group_info(group)
    if member in info[3]:
        return True
    else:
        return False

def group_add_member(group, member):
    cmd = [GPASSWD, '-a', member, group]
    debug("Arguments to gpasswd: %s" % (" ".join(cmd)))
    rc = subprocess.call(cmd, shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    if rc == 0:
        return True
    else:
        return False

def group_del_member(group, member):
    cmd = [GPASSWD, '-d', member, group]
    debug("Arguments to gpasswd: %s" % (" ".join(cmd)))
    rc = subprocess.call(cmd, shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    if rc == 0:
        return True
    else:
        return False

def group_exists(group):
    try:
        if grp.getgrnam(group):
            return True
    except KeyError:
        return False

def group_info(group):
    if not group_exists(group):
        return False
    try:
        info = list(grp.getgrnam(group))
    except KeyError:
        return False
    return info
    
# ===========================================

if not os.path.exists(GROUPADD):
    if os.path.exists("/sbin/groupadd"):
        GROUPADD = "/sbin/groupadd"
    else:
        fail_json(msg="Cannot find groupadd")
if not os.path.exists(GROUPDEL):
    if os.path.exists("/sbin/groupdel"):
        GROUPDEL = "/sbin/groupdel"
    else:
        fail_json(msg="Cannot find groupdel")
if not os.path.exists(GROUPMOD):
    if os.path.exists("/sbin/groupmod"):
        GROUPDEL = "/sbin/groupmod"
    else:
        fail_json(msg="Cannot find groupmod")
if not os.path.exists(GPASSWD):
    if os.path.exists("/bin/gpasswd"):
        GROUPDEL = "/bin/gpasswd"
    else:
        fail_json(msg="Cannot find gpasswd")

if len(sys.argv) == 2 and os.path.exists(sys.argv[1]):
    argfile = sys.argv[1]
    args    = open(argfile, 'r').read()
else:
    args = ' '.join(sys.argv[1:])
items   = shlex.split(args)

if not len(items):
    fail_json(msg='the module requires arguments -a')
    sys.exit(1)

params = {}
for x in items:
    (k, v) = x.split("=")
    params[k] = v

state       = params.get('state','present')
name        = params.get('name', None)
gid         = params.get('gid', None)

# ===========================================
# the following controls group membership
member      = params.get('member', None)
memberstate = params.get('memberstate', 'present')

if state not in [ 'present', 'absent' ]:
    fail_json(msg='invalid state')
if memberstate not in [ 'present', 'absent' ]:
    fail_json(msg='invalid memberstate')
if name is None:
    fail_json(msg='name is required')

changed = False
rc = 0
if state == 'absent':
    if group_exists(name):
        changed = group_del(name)
    exit_json(name=name, changed=changed)
elif state == 'present':
    if not group_exists(name):
        changed = group_add(name, gid=gid)
    else:
        changed = group_mod(name, gid=gid)

    if member is not None:
        if memberstate == 'present':
            if not group_has_member(name, member):
                changed = group_add_member(name, member)
        elif memberstate == 'absent':
            if group_has_member(name, member):
                changed = group_del_member(name, member)
        else:
            fail_json(name=name, msg='Unexpected position reached')

    exit_json(name=name, changed=changed)

fail_json(name=name, msg='Unexpected position reached')