Use facts gathered by ansible programmatically

Question

I'd like to write a Python program that uses the facts that Ansible gives me with ansible HOST -m setup.

When I call this, I get a response which makes it only almost pure JSON:

$ ansible localhost -m setup
localhost | success >> {
    // actual data
}

Is there some way to get this JSON response directly without parsing the shell output (which might not be too stable)? Could I even use Ansible directly in a Python 3 program?

Answer 1

version stable-2.2, stable-2.3, and 2.4+

The latest ansible releases for 2.2, 2.3, and 2.4 all support ANSIBLE_STDOUT_CALLBACK variable. To use it, you need to add an ansible.cfg file that looks like:

[defaults]
bin_ansible_callbacks = True
callback_plugins = ~/.ansible/callback_plugins

You can place it wherever you're using ansible. Then, you need to create the callback_plugins directory, if you haven't already. Finally, you need to add a custom json parser to the directory. I copied the json parser that is bundled with ansible to the callback_plugins directory, then edited a single line in it to make it work.

I found the json.py file by first executing ansible --version

$ ansible --version
ansible 2.4.0.0
    config file = /Users/artburkart/Code/ansible.cfg
    configured module search path = [u'/Users/artburkart/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
    ansible python module location = /usr/local/lib/python2.7/site-packages/ansible
    executable location = /usr/local/bin/ansible
    python version = 2.7.13 (default, Jul 18 2017, 09:17:00) [GCC 4.2.1 Compatible Apple LLVM 8.1.0 (clang-802.0.42)]

Then using the "ansible python module location" to find the json.py.

cp /usr/local/lib/python2.7/site-packages/ansible/plugins/callback/json.py ~/.ansible/callback_plugins/

Finally I edited the v2_runner_on_ok function in the json.py file to look like this (courtesy of armab on GitHub):

def v2_runner_on_ok(self, result, **kwargs):
    host = result._host
    self.results[-1]['tasks'][-1]['hosts'][host.name] = result._result
    print(json.dumps({host.name: result._result}, indent=4))

Once that was all set up, the command is very simple:

ANSIBLE_STDOUT_CALLBACK=json ansible all -i localhost, -c local -m setup | jq

If you always want to parse JSON output, you can add the following line to the end of the ansible.cfg file I described above.

stdout_callback = json

That way, you don't need to include the environment variable anymore.

versions <= latest 2.2 stable

When querying against instances, I use the following command:

ansible all --inventory 127.0.0.1, --connection local --module-name setup | sed '1 s/^.*|.*=>.*$/{/g'

If you pipe the output into jq, as leucos suggested, it happily parses the semi-valid JSON. For example:

ansible all -i hosts -m setup | sed '1 s/^.*|.*=>.*$/{/g' | jq -r '.ansible_facts.ansible_distribution'
CentOS
Ubuntu