Add NextDNS system health (#74368)

Add system_health

homeassistant/components/nextdns/strings.json

@@ -20,5 +20,10 @@
     "abort": {
       "already_configured": "This NextDNS profile is already configured."
     }
+  },
+  "system_health": {
+    "info": {
+      "can_reach_server": "Reach server"
+    }
   }
 }

homeassistant/components/nextdns/system_health.py

@@ -0,0 +1,25 @@
+"""Provide info to system health."""
+from __future__ import annotations
+
+from typing import Any
+
+from nextdns.const import API_ENDPOINT
+
+from homeassistant.components import system_health
+from homeassistant.core import HomeAssistant, callback
+
+
+@callback
+def async_register(  # pylint:disable=unused-argument
+    hass: HomeAssistant,
+    register: system_health.SystemHealthRegistration,
+) -> None:
+    """Register system health callbacks."""
+    register.async_register_info(system_health_info)
+
+
+async def system_health_info(hass: HomeAssistant) -> dict[str, Any]:
+    """Get info for the info page."""
+    return {
+        "can_reach_server": system_health.async_check_can_reach_url(hass, API_ENDPOINT)
+    }

tests/components/nextdns/test_system_health.py

@@ -0,0 +1,40 @@
+"""Test NextDNS system health."""
+import asyncio
+
+from aiohttp import ClientError
+from nextdns.const import API_ENDPOINT
+
+from homeassistant.components.nextdns.const import DOMAIN
+from homeassistant.setup import async_setup_component
+
+from tests.common import get_system_health_info
+
+
+async def test_nextdns_system_health(hass, aioclient_mock):
+    """Test NextDNS system health."""
+    aioclient_mock.get(API_ENDPOINT, text="")
+    hass.config.components.add(DOMAIN)
+    assert await async_setup_component(hass, "system_health", {})
+
+    info = await get_system_health_info(hass, DOMAIN)
+
+    for key, val in info.items():
+        if asyncio.iscoroutine(val):
+            info[key] = await val
+
+    assert info == {"can_reach_server": "ok"}
+
+
+async def test_nextdns_system_health_fail(hass, aioclient_mock):
+    """Test NextDNS system health."""
+    aioclient_mock.get(API_ENDPOINT, exc=ClientError)
+    hass.config.components.add(DOMAIN)
+    assert await async_setup_component(hass, "system_health", {})
+
+    info = await get_system_health_info(hass, DOMAIN)
+
+    for key, val in info.items():
+        if asyncio.iscoroutine(val):
+            info[key] = await val
+
+    assert info == {"can_reach_server": {"type": "failed", "error": "unreachable"}}