generator – Uses Jinja2 to construct hosts and groups from patterns

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< Inventory PluginsAnsible/docs/2.7/plugins/inventory/generator


generator – Uses Jinja2 to construct hosts and groups from patterns

New in version 2.6.


Synopsis

  • Uses a YAML configuration file with a valid YAML or .config extension to define var expressions and group conditionals
  • Create a template pattern that describes each host, and then use independent configuration layers
  • Every element of every layer is combined to create a host for every layer combination
  • Parent groups can be defined with reference to hosts and other groups using the same template variables

Parameters

Parameter Choices/Defaults Configuration Comments

hosts

-

The name key is a template used to generate hostnames based on the layers option. Each variable in the name is expanded to create a cartesian product of all possible layer combinations.

The parents are a list of parent groups that the host belongs to. Each parent item contains a name key, again expanded from the template, and an optional parents key that lists its parents.

Parents can also contain vars, which is a dictionary of vars that is then always set for that variable. This can provide easy access to the group name. E.g set an application variable that is set to the value of the application layer name.

layers

-

A dictionary of layers, with the key being the layer name, used as a variable name in the host name and parents keys. Each layer value is a list of possible values for that layer.

plugin

- / required

  • generator

token that ensures this is a source file for the 'generator' plugin.



Examples

# inventory.config file in YAML format
plugin: generator
strict: False
hosts:
    name: "{{ operation }}-{{ application }}-{{ environment }}-runner"
    parents:
      - name: "{{ operation }}-{{ application }}-{{ environment }}"
        parents:
          - name: "{{ operation }}-{{ application }}"
            parents:
              - name: "{{ operation }}"
              - name: "{{ application }}"
          - name: "{{ application }}-{{ environment }}"
            parents:
              - name: "{{ application }}"
                vars:
                  application: "{{ application }}"
              - name: "{{ environment }}"
                vars:
                  environment: "{{ environment }}"
      - name: runner
layers:
    operation:
        - build
        - launch
    environment:
        - dev
        - test
        - prod
    application:
        - web
        - api

Status

Authors

  • UNKNOWN

Hint

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© 2012–2018 Michael DeHaan
© 2018–2019 Red Hat, Inc.
Licensed under the GNU General Public License version 3.
https://docs.ansible.com/ansible/2.7/plugins/inventory/generator.html