subelements – traverse nested key from a list of dictionaries

New in version 1.4.

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

Parameter	Choices/Defaults	Configuration	Comments
_terms - / required			tuple of list of dictionaries and dictionary key to extract
skip_missing -	Default: "no"		If set to True, the lookup plugin will skip the lists items that do not contain the given subkey. If False, the plugin will yield an error and complain about the missing subkey.

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:

Key	Returned	Description
_list -		list of subelements extracted

Status

Authors

• Serge van Ginderachter <serge@vanginderachter.be>

Hint

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