assert_process

#!/usr/bin/python
# -*- coding: utf-8 -*-

# (c) 2014, Will Thames <will@thames.id.au>
# (c) 2014, Allan Denot <adenot@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/>.

import pprint

DOCUMENTATION = '''
---
module: assert_process
version_added: 1.5
short_description: Check the status of a process
description:
  - Check if a process is running or not
options: 
  name: 
    description:
    - name of the process to check
    required: True
    default: null
  with_args:
    description:
    - list of one or more arguments to look for
    required: False
    default: []
  should_be: 
    description: 
    - state of the process
    choices: [ 'running', 'stopped' ]
    required: True
author: Will Thames
'''

EXAMPLES = '''
# Check if http app is running
assert_process: name=httpd should_be=running with_args='/apps/apache2/conf/httpd.conf'
'''

def check_process(process, name):
    if not len(process.strip().split()):
        return False
        
    if process.strip().split()[0] == name:
        return True
    return False

def check_arguments(process,name,args):
    if not len(process.strip().split()):
        return False

    arg_found = 0
    for arg in args:
        if arg in ' '.join(process.split()[1:]):
            arg_found += 1
    if arg_found == len(args): 
        return True
    return False
    
def main():
    module = AnsibleModule(
        argument_spec = dict(
            name=dict(required=True, default=None),
            with_args=dict(type='list', required=False, default=[]),
            should_be=dict(choices=['running', 'stopped'],required=True),
        ),
        supports_check_mode=True
    )
    name = module.params.get('name')
    args = module.params.get('with_args')
    state = module.params.get('should_be')
    
    # Would like this to be more cross platform
    rc, stdout, stderr = module.run_command(['ps', 'axww', '-o', 'command'])
    processes = stdout.split('\n')[1:]
    
    process_running = filter(lambda x: check_process(x, name), processes)
    process_args = filter(lambda x: check_arguments(x, name, args), processes)
    if state == 'running':
        if not process_running:
            module.fail_json(msg="%s is not running" % name)
    
        if args and not process_args:
            module.fail_json(msg="%s is running but does not have all the arguments required: %s" % (name, args))
    
        if process_running:
            module.exit_json()

    if state == 'stopped':
        if process_running:
            module.fail_json(msg="%s is running, it should be stopped" % name)
        else:
            module.exit_json()

# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()