Ansible ND 4.X | WIP | ND Manage Policies Module + Pydantic Models + Smart Endpoints

[nikhilsrikrishna]

This PR adds the nd_policy module for switch policy management in the cisco.nd collection, including the core resource handler, endpoint wrappers, and Pydantic models.

What's Included

• Policy resource handler — nd_policy_resources.py supports gathered, merged, and deleted states. Uses bulk create, bulk delete with 207 response handling, the mark-delete → push-config → remove pipeline, and deploy through switch actions.

• Endpoint definitions — Three endpoint classes: manage_fabrics_policies.py, manage_fabrics_policy_actions.py, manage_fabrics_switch_actions.py.

• Pydantic model layer — Model classes: config_models.py, gathered_models.py, policy_actions.py, policy_base.py, policy_crud.py. These cover input validation, API response parsing, and gathered output formatting.

• Input aliasing — switch_id is aliased as switch_ip in the argument spec, allowing users to specify either name interchangeably. Pydantic validators normalize both to the field expected by the API.

• Template inputs validation — User-provided template_inputs are validated at runtime against the template's parameter schema fetched from the controller, checking for unknown keys, missing required parameters, and basic type correctness. System-injected keys are stripped from gathered output so only user-defined variables are returned.

• Unit tests — Endpoint-level tests covering all three endpoint classes.

Notes

• Delete workflow — Delete follows a 3-step flow: markDelete → pushConfig → remove. PYTHON content-type templates (e.g., switch_freeform, Ext_VRF_Lite_SVI) fail on markDelete with "Content type is PYTHON, cannot mark for deletion". Instead of maintaining a hardcoded list of these template names, the module inspects the 207 response — any policy that fails with this specific message is automatically retried via direct DELETE /policies/{policyId}, then deployed via switchActions/deploy to push the config removal to the switch.

• Gathered state and policy_id — The gathered output includes a policy_id field (e.g., POLICY-28440) alongside the template name. When this output is fed back into state=merged, the policy_id can be directly used to identify the exact policy.

Work In Progress

• ND output format structure
• Integration tests