Extending_Ansible

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This wiki page has been moved to [docs](https://github.com/reallyenglish/ansible-role-example/tree/master/docs) and is no longer maintained.

Table of Contents

• Filter plugin
  • Example
• Test plugin
  • Example

Filter plugin

You can create your own filter under filter_plugins.

Example

ansible-role-resolver/filter_plugins/predictable_shuffle.py has a filter.

from ansible import errors
import hashlib
import itertools

def predictable_shuffle(array, key):
    ''' returns a predictable_shuffled list '''
    nameservers_permutation = list(itertools.permutations(array))
    number_of_permutation = len(nameservers_permutation)
    index = int(hashlib.sha256(key).hexdigest(), 16) % number_of_permutation
    return nameservers_permutation[index]

class FilterModule(object):
    ''' A filter to predictable_shuffle a list '''
    def filters(self):
        return {
            'predictable_shuffle' : predictable_shuffle,
        }

Test plugin

You can create your own test plugins under test_plugins.

Example

jinja2 2.7 or older does not have equalto test. To use the test in older jinja, create test_plugins/equalto.py.

from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

from ansible import errors

def equalto(value, other):
    return bool(value == other)

class TestModule(object):
    ''' Ansible file jinja2 tests '''

    def tests(self):
        return {
            'equalto' : equalto,
        }

Now equalto test is available in the role.

Action plugin

To create a module in a role, create an action plugin.

Register an action in action_plugins.

# action_plugins/logrotate.py

from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

from ansible.plugins.action import ActionBase

try:
    from __main__ import display
except ImportError:
    from ansible.utils.display import Display
    display = Display()


# a wrapper action module for logrotate module
class ActionModule(ActionBase):

    def run(self, tmp=None, task_vars=None):
        if task_vars is None:
            task_vars = dict()

        result = super(ActionModule, self).run(tmp, task_vars)

        logrotate_conf_d = self._templar.template(task_vars['logrotate_conf_d'])
        display.vv("logrotate_conf_d: %s" % logrotate_conf_d)

        if not 'config_dir' in self._task.args:
            self._task.args['config_dir'] = logrotate_conf_d

        result.update(self._execute_module(module_name='logrotate', module_args=self._task.args, task_vars=task_vars))

        return result

Create the module in library, such as library/logrotate.py. ansible-role-logrotate has an logrotate action and module.

See Developing Modules for writing a module.