We’ve got a web based front end in our CRM which triggers Ansible Playbooks for provisioning of customer services, this works really well, except I’d been facing a totally baffling issue of late.

Ansible Plays (Provisioning jobs) would have variables set that they inherited from other Ansible Plays, essentially if I set a variable in Play X and then ran Play Y, the variable would still be set.

I thought this was an issue with our database caching the play data showing the results from a previous play, that wasn’t the case.

Then I thought our API that triggers this might be passing extra variables in that it had cached, wasn’t the case.

In the end I ran the Ansible function call in it’s simplest possible form, with no API, no database, nothing but plain vanilla Ansible called from Python

    # Run the actual playbook
    r = ansible_runner.run(
        private_data_dir='/tmp/',
        playbook=playbook_path,
        extravars=extra_vars,
        inventory=inventory_path,
        event_handler=event_handler_obj.event_handler,
        quiet=False
    )

And I still I had the same issue of variables being inherited.

So what was the issue? Well the title gives it away, the private_data_dir parameter creates a folder in that directory, called env/extravars which a JSON file lives with all the vars from all the provisioning runs.

Removing the parameter from the Python function call resolved my issue, but did not give me back the half a day I spent debugging this…