ssh_keys.yml

# This playbook synchronizes SSH keys in
# ~/.ssh/authorized_keys with the public
# keys of the user's GitHub profile
---
- name: SSH keys
  hosts: all
  pre_tasks:

    - name: Find GitHub username from git config
      shell: git config github.user
      register: __default_github_user
      when: (github_username is undefined) or (github_username is none) or (github_username | trim == '')

    - name: Set GitHub username from git config
      set_fact: github_username="{{ __default_github_user.stdout }}"
      when: ((github_username is undefined) or (github_username is none) or (github_username | trim == '')) and ((__default_github_user|succeeded) and (__default_github_user.stdout | trim != ''))

    - name: Validate GitHub username presence
      fail: msg="github_username variable is not set and 'git config github.user' is not helpful"
      when: (github_username is undefined) or (github_username is none) or (github_username | trim == '')

    - name: Adding some verbosity
      debug: msg="Adding SSH keys from https://github.com/{{ github_username }}.keys to {{ ansible_user }}"

    - name: Fetching GitHub keys
      authorized_key: key="https://github.com/{{ github_username }}.keys" user="{{ ansible_user }}"