etckeeper

#!/usr/bin/env python

# To test this, use:
#
#   mkdir test
#   export ETCKEEPER_DIR="$(realpath test)"
#   etckeeper init
#   ansible localhost -m "etckeeper" -a "action=begin"
#   ansible localhost -m "etckeeper" -a "action=commit msg=..."


DOCUMENTATION = '''
---
module: etckeeper
short_description: Provides a concise way to invoke etckeeper before and after plays.
'''

EXAMPLES = '''
# Put this at the beginning of all plays.
# It ensures that the play starts with a clean /etc.
- etckeeper: action=begin

# Put this at the end of all normal plays.
# If there were changes in /etc, it'll commit them.
- etckeeper: action=commit msg="foo"

# Put this at the end of all plays only including other plays.
# It does the same thing "begin" does: ensuring /etc is clean.
- etckeeper: action=end

# If you want, you can add the git revision of the playbook
# to the commit messages:
- set_fact:
    revision: "{{ lookup('pipe', 'cd \"%s\" ; git rev-parse HEAD' % playbook_dir) }}"
- etckeeper: "action=commit msg='foo' rev={{ revision }}"

# There are two notable exceptions:
#
# 1. A role responsible for installing etckeeper can't use "etckeeper action=begin"
#    during the first run, because etckeeper won't be available yet. However,
#    during subsequent runs, you actually do want action=begin to ensure /etc is clean.
#    The solution is:
- etckeeper: action=begin ignore_missing_etckeeper=yes

# 2. etckeeper will create commits during package management actions automatically.
#    Therefore, apt/yum/... tasks should be outside (ideally: before) an etckeeper begin/end.
'''

from os.path import exists
from ansible.module_utils.basic import *
import distutils.spawn

def main():

    module = AnsibleModule(
        supports_check_mode=True,
        argument_spec={
            'action': dict(required=True, choices=['begin', 'commit', 'end']),
            'ignore_missing_etckeeper': dict(default='no', choices=['yes', 'no']),
            'msg': dict(),
            'rev': dict(),
        }
    )

    if not distutils.spawn.find_executable('etckeeper'):
        if module.params['ignore_missing_etckeeper']:
            module.exit_json()

    rc, out, err = module.run_command(['etckeeper', 'unclean'])
    if err:
        module.fail_json(msg=err)
    is_clean = (rc != 0)

    if module.params['action'] in ('begin', 'end'):
        if is_clean:
            module.exit_json()
        else:
            module.fail_json(msg='/etc is not clean')


    elif module.params['action'] == 'commit':
        if module.check_mode:
            if is_clean:
                module.exit_json(changed=False)
            else:
                module.fail_json(msg='/etc is supposed to remain clean in check mode')
        if not is_clean:
            msg = module.params['msg']
            if not msg:
                module.fail_json(msg='msg must not be empty')
            if module.params['rev']:
                msg += "\n\nRevision: " + module.params['rev']
            rc, out, err = module.run_command(['etckeeper', 'commit', msg], check_rc=True)
            if err:
                module.fail_json(msg=err)
        module.exit_json(changed=not is_clean)

    else:
        module.fail_json(msg='bad action: "%s"' % module.params['action'])


if __name__ == '__main__':
    main()