Ansible - Bootstrap python

When you’re starting hosts from scratch, you can avoid preinstalling python in your image or startup scripts by issuing a raw command in ansible in a pre_tasks section. This doesn’t require python to be available on the remote host, effectively bootstrapping it to continue with the playbook.

Here’s an example for debian-based hosts:

- hosts: my_host
  remote_user: my_user
  become: yes
  gather_facts: false

  pre_tasks:
  - name: Bootsrap Python2 for Ansible
    raw: bash -c "test -e /usr/bin/python || (apt -qqy update && apt install -qqy python-minimal)"
    register: output
    changed_when: output.stdout != ""
  - name: Gathering Facts
    setup: # Also known as gather_facts

Note: gather_facts is set to false since some advanced facts require running python code on the remote host, hence we disable it in the beginning and then re-run it using setup:

 
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