ansible-module-check-structure is a handy custom Ansible module allowing you assert the type of Ansible facts, and validate the structure (or schema) of dictionaries and lists.

This is done by crafting an Ansible fact in which each hierarcherical element is a string representing one of python's built-in types, apply this structure to a fact you want to check.

You may for instance want to check that each element of a list is a dictionary in which the foo key defined, and paired to a string value...

struct:
  - foo: str

... or check that each element of a list is an integer:

struct:
  - int

Possibilities are endless!

• Clone this repository to your Ansible role_path, or install via ansible-galaxy;

  ansible-galaxy install alexisfacques.ansible_module_check_structure

• Import the role in your playbooks before running any role or task that require the check_structure module:

  - hosts: all
    roles:
      - alexisfacques.ansible_module_check_structure
    tasks:
      - name: Ensure variable is a string
        check_structure:
          struct:
            - str
          var:
            -"{{ is_this_a_str }}"

Alternatively, if importing a role is too much of a hassle, you can store this module in the library directory defined in your ansible.cfg file (Default is a sub-directory called library in the directory that contains your playbooks):

[defaults]
library = /path/to/your/library

Examples of use can be found here.

This project is licensed under the MIT License - see the LICENSE file for details.