[BUG] Firewall system not working on VyOS 1.5 and 1.4

[pcfriek1987]

As discussed creating a separate bug for the Firewall part on Vyos 1.5

[Jarnster]

Dev Console error about failing to cache the firewall system configuration. But, It's offcourse a backend related bug.

API Response: When firewall is empty under the path:

1684-e6f5208653b89c81.js:1 ❌ Failed to cache important data: config:firewall Error: API error (500): {"success":false,"error":"Error communicating with VyOS router: Unexpected error: HTTP Error 400: Configuration under specified path is empty\n","data":null,"traceback":"Traceback (most recent call last):\n File "/app/client.py", line 501, in execute_request\n result = await make_api_request(\n ^^^^^^^^^^^^^^^^^^^^^^^\n ...<3 lines>...\n )\n ^\n File "/app/utils.py", line 166, in make_api_request\n raise VyOSAPIError(\n ...<3 lines>...\n )\nutils.VyOSAPIError: HTTP Error 400: Configuration under specified path is empty\n\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n File "/app/main.py", line 370, in api_config\n result = await method()\n ^^^^^^^^^^^^^^\n File "/app/client.py", line 70, in call\n return await self.client.execute_request(self.endpoint, self.op, self.path, **kwargs)\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n File "/app/client.py", line 524, in execute_request\n raise VyOSAPIError(f"Unexpected error: {str(e)}")\nclient.VyOSAPIError: Unexpected error: HTTP Error 400: Configuration under specified path is empty\n\n"}
at a (8045-ec8fe9e242da0d88.js:1:4662)
at async 8045-ec8fe9e242da0d88.js:1:1739
at async Promise.all (:3000/index 1)
at async 8045-ec8fe9e242da0d88.js:1:1952

**When actually setting a value in the firewall configuration section, don't forget to empty out the cache (backend and frontend) at "http://VYMANAGER_INSTANCE_IP:3000/dashboard/cache"

API response: When setting up the firewall configuration section

{"success":true,"data":{"bridge":{"name":{"a":{"rule":{"10":{}}}}}},"error":null}

Creating new rules in the firewall system fails
For simple rules, they also don't show up in the overview.