skolo/ansible/switchboard/prepare-mac-for-ansible.yml

# Install Python 3 so we can do more than issue 'raw' commands.
#
# You don't need to run this by hand; mac.yml will run it as necessary.
- hosts: all_mac
  gather_facts: false

  pre_tasks:
    - name: See if our version of Python is already installed.
      raw: /usr/local/bin/python3 --version
      register: local_python_version
      failed_when: false  # Tolerate the binary not being there.
      changed_when: false

    - name: Install Python 3 and prerequisites.
      when: local_python_version.stdout_lines[0] != "Python 3.9.6"
      block:
        - name: Check for Rosetta.
          raw: test -e /Library/Apple/usr/libexec/oah/libRosettaRuntime
          register: rosetta_present
          failed_when: false
          changed_when: false

        - name: Check architecture.
          raw: arch
          register: cpu_arch
          changed_when: false

        - name: Install Rosetta on ARM machines if it's absent.
          # The Python installer package isn't marked as being ARM-native, so it
          # refuses to run unless Rosetta 2 is around. This is true up to and
          # including the 3.10.1 universal2 installer.
          become: true
          when: rosetta_present.rc != 0 and cpu_arch.stdout_lines[0] == "arm64"
          raw: softwareupdate --install-rosetta --agree-to-license

        - name: Install Python 3.
          vars:
            # Contains universal binaries. Happily runs on macOS 10.9+, despite
            # name.
            python_pkg: python-3.9.6-macos11.pkg
          block:
            - name: Download Python installer.
              # Works even if the file is already there:
              raw: curl -O 'https://www.python.org/ftp/python/3.9.6/{{ python_pkg }}' --output-dir ~{{ skolo_account }}/Downloads

            - name: Run installer.
              become: true
              raw: /usr/sbin/installer -verboseR -package ~{{ skolo_account }}/Downloads/{{ python_pkg }} -target /