Add proxmox_nic module (#2449)

* Add proxmox_nic module

Add proxmox_nic module to manage NIC's on Qemu(KVM) VM's in a Proxmox VE
cluster.
Update proxmox integration tests and add tests for proxmox_nic module.

This partially solves https://github.com/ansible-collections/community.general/issues/1964#issuecomment-790499397
and allows for adding/updating/deleting network interface cards after
creating/cloning a VM.

The proxmox_nic module will keep MAC-addresses the same when updating a
NIC. It only changes when explicitly setting a MAC-address.

* Apply suggestions from code review

Co-authored-by: Felix Fontein <felix@fontein.de>

* Add check_mode and implement review comments

- check_mode added
- some documentation updates
- when MTU is set, check if the model is virtio, else fail
- trunks can now be provided as list of ints instead of vlanid[;vlanid...]

* Make returns on update_nic and delete_nic more readable

Co-authored-by: Felix Fontein <felix@fontein.de>

* Increase readability on update_nic and delete_nic

* Implement check in get_vmid

- get_vmid will now fail when multiple vmid's are returned as proxmox
  doesn't guarantee uniqueness
- remove an unused import
- fix a typo in an error message

* Add some error checking to get_vmid

- get_vmid will now return the error message when proxmoxer fails
- get_vmid will return the vmid directly instead of a list of one
- Some minor documentation updates

* Warn instead of fail when setting mtu on unsupported nic

- When setting the MTU on an unsupported NIC model (virtio is the only
  supported model) this module will now print a warning instead of
  failing.
- Some minor documentation updates.

* Take advantage of proxmox_auth_argument_spec

Make use of proxmox_auth_argument_spec from plugins/module_utils/proxmox.py
This provides some extra environment fallbacks.

* Add blank line to conform with pep8

Co-authored-by: Felix Fontein <felix@fontein.de>

tests/integration/targets/proxmox/tasks/main.yml

@@ -48,7 +48,7 @@
     api_token_secret: "{{ api_token_secret | default(omit) }}"
     validate_certs: "{{ validate_certs }}"
   register: results
-  
+
 - assert:
     that:
     - results is not changed
@@ -226,6 +226,92 @@
         - results_action_current.vmid == {{ vmid }}
         - results_action_current.msg == "VM test-instance with vmid = {{ vmid }} is running"
 
+- name: VM add/change/delete NIC
+  tags: [ 'nic' ]
+  block:
+    - name: Add NIC to test VM
+      proxmox_nic:
+        api_host: "{{ api_host }}"
+        api_user: "{{ user }}@{{ domain }}"
+        api_password: "{{ api_password | default(omit) }}"
+        api_token_id: "{{ api_token_id | default(omit) }}"
+        api_token_secret: "{{ api_token_secret | default(omit) }}"
+        validate_certs: "{{ validate_certs }}"
+        vmid: "{{ vmid }}"
+        state: present
+        interface: net5
+        bridge: vmbr0
+        tag: 42
+      register: results
+
+    - assert:
+        that:
+        - results is changed
+        - results.vmid == {{ vmid }}
+        - results.msg == "Nic net5 updated on VM with vmid {{ vmid }}"
+
+    - name: Update NIC no changes
+      proxmox_nic:
+        api_host: "{{ api_host }}"
+        api_user: "{{ user }}@{{ domain }}"
+        api_password: "{{ api_password | default(omit) }}"
+        api_token_id: "{{ api_token_id | default(omit) }}"
+        api_token_secret: "{{ api_token_secret | default(omit) }}"
+        validate_certs: "{{ validate_certs }}"
+        vmid: "{{ vmid }}"
+        state: present
+        interface: net5
+        bridge: vmbr0
+        tag: 42
+      register: results
+
+    - assert:
+        that:
+        - results is not changed
+        - results.vmid == {{ vmid }}
+        - results.msg == "Nic net5 unchanged on VM with vmid {{ vmid }}"
+
+    - name: Update NIC with changes
+      proxmox_nic:
+        api_host: "{{ api_host }}"
+        api_user: "{{ user }}@{{ domain }}"
+        api_password: "{{ api_password | default(omit) }}"
+        api_token_id: "{{ api_token_id | default(omit) }}"
+        api_token_secret: "{{ api_token_secret | default(omit) }}"
+        validate_certs: "{{ validate_certs }}"
+        vmid: "{{ vmid }}"
+        state: present
+        interface: net5
+        bridge: vmbr0
+        tag: 24
+        firewall: True
+      register: results
+
+    - assert:
+        that:
+        - results is changed
+        - results.vmid == {{ vmid }}
+        - results.msg == "Nic net5 updated on VM with vmid {{ vmid }}"
+
+    - name: Delete NIC
+      proxmox_nic:
+        api_host: "{{ api_host }}"
+        api_user: "{{ user }}@{{ domain }}"
+        api_password: "{{ api_password | default(omit) }}"
+        api_token_id: "{{ api_token_id | default(omit) }}"
+        api_token_secret: "{{ api_token_secret | default(omit) }}"
+        validate_certs: "{{ validate_certs }}"
+        vmid: "{{ vmid }}"
+        state: absent
+        interface: net5
+      register: results
+
+    - assert:
+        that:
+        - results is changed
+        - results.vmid == {{ vmid }}
+        - results.msg == "Nic net5 deleted on VM with vmid {{ vmid }}"
+
 - name: VM stop
   tags: [ 'stop' ]
   block: