Fix(inventory_to_container): Add return guard if no children in inven…

[guillaumeVilar]

Change Summary

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Documentation content changes
• Other (please describe):

Related Issue(s)

Fixes #939

Component(s) name

arista.avd.eos_config_deploy_cvp

Proposed changes

Add a return guard in avd/plugins/modules/inventory_to_container.py in the get_devices() function in order to avoid the cast issue.

How to test

Playbook:

- hosts: cv_server
  tasks:
    - name: deploy configuration via CVP
      import_role:
         name: arista.avd.eos_config_deploy_cvp
      vars:
        container_root: 'DC1_FABRIC'
        configlets_prefix: 'DC1-AVD'
        device_filter: 'DC1'
        state: present
        execute_tasks: false

Inventory:

    # DC1_Fabric - EVPN Fabric running in home lab
    DC1:
      children:
        DC1_FABRIC:
          children:
            DC1_SPINES:
              hosts:
                DC1-SPINE1:
                  ansible_host: 10.0.0.1
                DC1-SPINE2:
                  ansible_host: 10.0.0.2
            DC1_L3LEAFS:
              children:
                DC1_LEAF1:
                  hosts:
                    DC1-LEAF1A:
                      ansible_host: 10.0.0.3
                    DC1-LEAF1B:
                      ansible_host: 10.0.0.4
            DC1_L2LEAFS:
              children:

Checklist:

• My code has been rebased from devel before I start
• I have read the CONTRIBUTING document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have updated molecule CI testing accordingly
• All new and existing tests passed (pre-commit, make linting and make sanity-lint).

[carlbuchmann]

LGTM, validated with AVD validation lab!

Current Devel:

TASK [arista.avd.eos_config_deploy_cvp : generate intented variables] ********************************************************************************************************************************************************************
Friday 14 May 2021  18:53:38 -0400 (0:00:00.099)       0:00:00.149 ************ 
Friday 14 May 2021  18:53:38 -0400 (0:00:00.099)       0:00:00.148 ************ 
An exception occurred during task execution. To see the full traceback, use -vvv. The error was: AttributeError: 'NoneType' object has no attribute 'items'
fatal: [CVP-1]: FAILED! => changed=false 

With PR #940, the play ran successfully.