assert_file

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

# (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/>.


DOCUMENTATION = '''
---
module: assert_file
version_added: 1.5
short_description: Assert the state of a file or directory
description:
  - Check state of a file or directory
options: 
  name: 
    description:
    - path to the file or directory to check its state
    required: True
    default: null
  state:
    description:
    - Check for the state of the resource. Options are: C(directory), C(file), C(absent), C(hard), C(link)
    required: true
    choices: [ file, directory, absent, hard, link ]
  src:
    required: false
    default: null
    choices: []
    description:
      - path of the file to link to (applies only to C(state=link)). Will accept absolute,
        relative and nonexisting paths. Relative paths are not expanded.

author: Allan Denot
'''

EXAMPLES = '''
# Check if file exists and is not a directory or link
assert_file: name=/tmp/testlink should_be=file
'''

def main():
    module = AnsibleModule(
        argument_spec = dict(
            name=dict(required=True, default=None),
            to=dict(required=False),
            should_be=dict(choices=['file','directory','absent','hard','link'], required=True),
        ),
        supports_check_mode=True
    )
    state = module.params.get('should_be')
    src = module.params.get('to')

    path = os.path.expanduser(module.params['name'])

    if not os.path.isabs(path):
        module.fail_json(msg="'%s' must be an absolute path" % path)

    if src and not os.path.isabs(src):
        module.fail_json(msg="Link source '%s' must be an absolute path" % src)
        
    if os.path.lexists(path):
        if os.path.islink(path):
            actual_state = 'link'
        elif os.path.isdir(path):
            actual_state = 'directory'
        elif os.stat(path).st_nlink > 1:
            actual_state = 'hard'
        else:
            # could be many other things, but defaulting to file
            actual_state = 'file'
    else:
        if state == 'absent':
            module.exit_json()
        else:
            module.fail_json(msg="%s does not exist, it should exist with state '%s'" % (path,state))

    if state != actual_state:
        module.fail_json(msg="%s is %s, it should be %s" % (path,actual_state,state))

    if state in ['link','hard']:
        actual_src = os.path.join(os.path.dirname(path), os.path.basename(os.readlink(path)))
        if not os.path.exists(actual_src):
            module.fail_json(msg='%s links to %s, but it does not exist' % (path,actual_src))

        if state == 'link':
            if actual_src != src:
                module.fail_json(msg='%s links to %s, it should link to %s' % (path,actual_src,src))

    module.exit_json()
    

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