unable to specify allowed address pairs without mac

Summary

When creating port with network action when allowed_address_pairs is specified, action fails,

Steps to reproduce

Execute this playbook:

---
- hosts: localhost
  gather_facts: no
  vars:
    openstack_cloud: "YOUR_CLOUD_PROJECT"

    openstack_project_ports:
      - name: "test-port"
        network: "test-net"
        addresses:
          - subnetwork_name: "test-subnet"
        allowed_address_pairs:
          - ip_address: "192.168.1.100"
        security_groups:
          - "default"

    openstack_project_networks:
      - name: "test-net"
        subnet_name: "test-subnet"
        subnet_cidr: "192.168.1.0/24"
  tasks:
    - include_role: { name: "openstack", tasks_from: "network" }

Expected behavior

Everything should work fine.

Actual behavior

Creating port fails.

Relevant logs and/or screenshots

...
 _________________________________
< TASK [openstack : create ports] >
 ---------------------------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

included: /home/bdaca/Praca/ansible-playbooks/ansible-roles/openstack/tasks/network_ports_create.yml for localhost
 _____________________________________________
< TASK [openstack : geting openstack subnets] >
 ---------------------------------------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

ok: [localhost -> localhost]
 ___________________________________________
< TASK [openstack : geting openstack ports] >
 -------------------------------------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

ok: [localhost -> localhost]
 _____________________________________________________________
< TASK [openstack : check if subnetworks used in ports exist] >
 -------------------------------------------------------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

 ____________________________________________________
< TASK [openstack : check if subnetworks are unique] >
 ----------------------------------------------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

skipping: [localhost] => (item=test-subnet) 
 _________________________________
< TASK [openstack : create ports] >
 ---------------------------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

fatal: [localhost]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'unicode object' has no attribute 'mac_address'\n\nThe error appears to have been in '/home/bdaca/Praca/ansible-playbooks/ansible-roles/openstack/tasks/network_ports_create.yml': line 30, column 3, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n# related issue: https://github.com/ansible/ansible/issues/47182\n- name: \"create ports\"\n  ^ here\n"}

Possible fixes

The problem is with this variable definition:

_openstack_port_in_openstack_ports: |
  {{
    openstack_ports
    | selectattr('name', 'equalto', port.name)
    | first
    | default()
  }}

When port does not exist, this variable has "\n" value instead of being empty. Just add - behind |.