Lookups

Lookup plugins retrieve data from outside sources such as files, databases, key/value stores, APIs, and other services. Like all templating, lookups execute and are evaluated on the Ansible control machine. Ansible makes the data returned by a lookup plugin available using the standard templating system. Before Ansible 2.5, lookups were mostly used indirectly in with_<lookup> constructs for looping. Starting with Ansible 2.5, lookups are used more explicitly as part of Jinja2 expressions fed into the loop keyword.

Using lookups in variables

You can populate variables using lookups. Ansible evaluates the value each time it is executed in a task (or template).

vars:
  motd_value: "{{ lookup('file', '/etc/motd') }}"
tasks:
  - debug:
      msg: "motd value is {{ motd_value }}"

For more details and a list of lookup plugins in ansible-core, see Working with plugins. You may also find lookup plugins in collections. You can review a list of lookup plugins installed on your control machine with the command ansible-doc -l -t lookup.