Cannot access groups of a host from within a callback plugin

[rawbertp]

ISSUE TYPE

• Bug Report

COMPONENT NAME

callback plugins

ANSIBLE VERSION

ansible 2.1.0 (devel 0ced20951f) last updated 2016/04/12 14:12:44 (GMT +200)
  lib/ansible/modules/core: (detached HEAD c52f475c64) last updated 2016/04/12 14:12:50 (GMT +200)
  lib/ansible/modules/extras: (detached HEAD 5abb914315) last updated 2016/04/12 14:12:53 (GMT +200)
  config file = /home/robert/Documents/sandbox/ansible_callback_plugin_sandbox/ansible.cfg
  configured module search path = Default w/o overrides

CONFIGURATION

OS / ENVIRONMENT

SUMMARY

In a callback plugin, in the method v2_runner_on_failed(self, result, ignore_errors=False) I want to retrieve the groups of a host but it always returns an empty list.

STEPS TO REPRODUCE

Please see https://github.com/rawbertp/ansible_callback_plugin_issue/blob/master/plugins/callback_plugins/dummy.py and code below.

The group var "foo" is set in group_vars/all (="all"), group_vars/prod (="prod") and group_vars/test (="test").

Now I run my playbook as follows:

ansible-playbook -i inventory/test main.yml
ansible-playbook -i inventory/prod main.yml

Running it for "inventory/test" I'd expect the callback plugin to return "test" as a value for foo whereas for "inventory/prod" it should be prod. However, it always returns "all".

The line
self.play._variable_manager.get_vars(self.loader, play=self.play, task=result._task, host=result._host, use_cache=False)

only returns group vars set in "all".

The problem is that result._host.get_groups() always returns an empty [] list.

class CallbackModule(CallbackBase):
    def __init__(self):
        super(CallbackModule, self).__init__()
        logging.basicConfig(stream=sys.stderr, level=logging.DEBUG)

    def v2_runner_on_failed(self, result, ignore_errors=False):
        logging.debug("+++++ v2_runner_on_failed")

        logging.debug("host.get_groups(): ->")
        logging.debug(result._host.get_groups())

        #epdb.st()

        # Haven't managed it yet to get the actual effective group vars...
        # The problem is that result._host.get_groups() returns an empty list!
        # (Epdb) result._host
        # localhost
        # (Epdb) result._host.get_groups()
        # [] <---

        x = self.play._variable_manager.get_vars(self.loader, play=self.play, task=result._task, host=result._host, use_cache=False)

        logging.debug("Var from 'all' group_vars: " + x.get("foo"))


    def v2_playbook_on_start(self, playbook):
        logging.debug("+++++ v2_playbook_on_start")
        self.playbook = playbook


    def v2_playbook_on_play_start(self, *args, **kwargs):
        logging.debug("v2_playbook_on_play_start(self, *args, **kwargs)")
        self.play = args[0]  # Workaround for https://github.com/ansible/ansible/issues/13948
        self.loader = args[0]._loader

EXPECTED RESULTS

In my example (https://github.com/rawbertp/ansible_callback_plugin_issue/) I'd expect result._host.get_groups()
to return [frontend, prod] or [frontend, test] depending on the inventory chosen and self.play._variable_manager.get_vars(self.loader, play=self.play, task=result._task, host=result._host, use_cache=False)
to return the actually effective vars for the task.

inventory/prod -> foo == "prod"
inventory/test -> foo == "test"

ACTUAL RESULTS

result._host.get_groups() always returns an empty [] list.
self.play._variable_manager.get_vars(self.loader, play=self.play, task=result._task, host=result._host, use_cache=False) only returns the "all" group vars.

inventory/prod -> foo == "all"
inventory/test -> foo == "all"

[jhawkesworth]

Not sure if this is what you need, but fairly certain it will get get group vars from groups other than the 'all' group like this.

    def v2_playbook_on_play_start(self, *args, **kwargs):
        hosts = args[0].get_variable_manager()._inventory.get_hosts()
        for host in hosts:
            host_grp_vars = host.get_group_vars()

[rawbertp]

Thanks for this hint. This seems to do the trick as a workaround.

    def v2_playbook_on_play_start(self, *args, **kwargs):
        ...
        self.hosts = args[0].get_variable_manager()._inventory.get_hosts()

    def v2_runner_on_failed(self, result, ignore_errors=False):
        ...
        host_name = result._host.name

        for host in self.hosts:
            if host.name == host_name:
                foo = host.get_group_vars().get("foo")

        logging.debug(foo)

Outcome:

• "foo" set in group var file: var taken from group_vars/
• "foo" not set in group var file: var taken from group_vars/all

Still, I wonder why result._host in v2_runner_on_failed returns an empty group list.

[bcoca]

not a bug, this info is not supplied on purpose, callbacks are given a narrow access to data.

The 'hack' above is not guaranteed to always work and is unsupported.

[ansibot]

cc @dharmabumstead
click here for bot help

[sivel]

Closing per above.

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