subelements – traverse nested key from a list of dictionaries

• Synopsis
• Parameters
• Examples
• Return Values
• Status

Synopsis

• Subelements walks a list of hashes (aka dictionaries) and then traverses a list with a given (nested sub-)key inside of those records.

Parameters

Examples

- name: show var structure as it is needed for example to make sense
  hosts: all
  vars:
    users:
      - name: alice
        authorized:
          - /tmp/alice/onekey.pub
          - /tmp/alice/twokey.pub
        mysql:
            password: mysql-password
            hosts:
              - "%"
              - "127.0.0.1"
              - "::1"
              - "localhost"
            privs:
              - "*.*:SELECT"
              - "DB1.*:ALL"
        groups:
          - wheel
      - name: bob
        authorized:
          - /tmp/bob/id_rsa.pub
        mysql:
            password: other-mysql-password
            hosts:
              - "db1"
            privs:
              - "*.*:SELECT"
              - "DB2.*:ALL"
  tasks:
    - name: Set authorized ssh key, extracting just that data from 'users'
      authorized_key:
        user: "{{ item.0.name }}"
        key: "{{ lookup('file', item.1) }}"
      with_subelements:
         - "{{ users }}"
         - authorized

    - name: Setup MySQL users, given the mysql hosts and privs subkey lists
      mysql_user:
        name: "{{ item.0.name }}"
        password: "{{ item.0.mysql.password }}"
        host: "{{ item.1 }}"
        priv: "{{ item.0.mysql.privs | join('/') }}"
      with_subelements:
        - "{{ users }}"
        - mysql.hosts

    - name: list groups for users that have them, don't error if groups key is missing
      debug: var=item
      loop: "{{lookup('subelements', users, 'groups', {'skip_missing': True})}}"

Return Values

Common return values are documented here, the following are the fields unique to this lookup:

Status

• This lookup is not guaranteed to have a backwards compatible interface. [preview]
• This lookup is maintained by the Ansible Community. [community]

Authors

• Serge van Ginderachter <serge@vanginderachter.be>