- hosts: webservers
  remote_user: jack

  tasks:
    - name: fetch all public keys
      shell: cat ~/.ssh/id_rsa.pub
      register: ssh_keys
      tags:
        - ssh

    - name: check ssh public keys
      debug: msg="{{ ssh_keys.stdout }}"
      tags:
        - ssh

    - name: deploy ssh keys
      shell: echo {{ ssh_keys.stdout }} >> ~/.ssh/authorized_keys
      delegate_to: "{{ item }}"
      with_items:
        - "{{groups['webservers']}}"
      tags:
        - ssh