feat: SNMP support — get_snmp_config(), fix_snmp action

get_snmp_config() calls GET /api/netsnmp/general/get with 5s timeout (plugin
may not be installed). fix_snmp installs os-net-snmp package, configures via
POST /api/netsnmp/general/set with community 'public', restarts service.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

napalm_opnsense/opnsense.py

@@ -1305,7 +1305,11 @@ class OPNsenseDriver(FirewallDriver):
                 status = self._get("/api/core/firmware/status")
                 state = status.get("status", "none")
                 if state in ("update", "upgrade"):
-                    updates = status.get("updates") or []
+                    updates = (
+                        status.get("upgrade_packages")
+                        or status.get("updates")
+                        or []
+                    )
                     return [
                         {
                             "name": u.get("name", ""),
@@ -1320,6 +1324,36 @@ class OPNsenseDriver(FirewallDriver):
                 pass
         return []
 
+    def get_device_warnings(self) -> List[Dict[str, Any]]:
+        """Return a list of warning dicts for issues detected on this device.
+
+        Reads the cached ``GET /api/core/firmware/status`` (no network
+        update trigger) to detect available package/firmware updates.
+        """
+        warnings: List[Dict[str, Any]] = []
+        try:
+            status = self._get("/api/core/firmware/status")
+            state = status.get("status", "none")
+            if state in ("update", "upgrade"):
+                upgrades = (
+                    status.get("upgrade_packages")
+                    or status.get("updates")
+                    or []
+                )
+                if upgrades:
+                    warnings.append({
+                        "code": "updates_available",
+                        "severity": "info",
+                        "action": None,
+                        "meta": {
+                            "count": len(upgrades),
+                            "packages": [u.get("name", "") for u in upgrades[:10]],
+                        },
+                    })
+        except Exception:
+            pass
+        return warnings
+
     def apply_updates(self, packages: List[str]) -> Dict[str, Any]:
         """Trigger a full firmware upgrade on OPNsense.
 
@@ -1388,3 +1422,102 @@ class OPNsenseDriver(FirewallDriver):
             return {"success": True, "output": str(result)}
         except Exception as exc:
             return {"success": False, "output": str(exc)}
+
+    # ── SNMP / Health ──────────────────────────────────────────────────────────
+
+    def get_snmp_config(self):
+        """Return SNMP config if the os-net-snmp plugin is installed and enabled.
+
+        Uses GET /api/netsnmp/general/get (os-net-snmp plugin API).
+        Returns None if the plugin is not installed or SNMP is disabled.
+        """
+        try:
+            from napalm_device_types.models import SNMPConfigDict
+        except ImportError:
+            return None
+
+        try:
+            # Short timeout — endpoint may not exist if os-net-snmp plugin is not installed
+            url = self.base_url.rstrip("/") + "/api/netsnmp/general/get"
+            response = self.session.get(url, timeout=5)
+            if response.status_code != 200:
+                return None
+            data = response.json()
+        except Exception:
+            return None
+
+        if not data:
+            return None
+
+        general = data.get("general", data)
+        enabled = str(general.get("enabled", "0")) == "1"
+        if not enabled:
+            return None
+
+        community = general.get("community", "public") or "public"
+        return SNMPConfigDict(running=True, community=community, port=161, version="2c")
+
+    def run_device_action(self, action: str) -> Dict[str, Any]:
+        """Execute a named action on the firewall."""
+        if action == "fix_snmp":
+            return self._action_fix_snmp()
+        raise NotImplementedError(f"Unknown action: {action!r}")
+
+    def _action_fix_snmp(self) -> Dict[str, Any]:
+        """Install os-net-snmp plugin, configure community 'public', start service.
+
+        Steps:
+        1. Install os-net-snmp via firmware API (idempotent — no-op if installed)
+        2. Configure via POST /api/netsnmp/general/set
+        3. Start/restart via POST /api/netsnmp/service/start
+        """
+        lines: list = []
+
+        # 1. Install os-net-snmp plugin (POST /api/core/firmware/install/os-net-snmp)
+        try:
+            result = self._post("/api/core/firmware/install/os-net-snmp")
+            lines.append(f"[install] {result}")
+        except Exception as exc:
+            lines.append(f"[install] skipped or already installed: {exc}")
+
+        # 2. Configure SNMP: enable + set community 'public'
+        try:
+            self._post("/api/netsnmp/general/set", {
+                "general": {
+                    "enabled": "1",
+                    "community": "public",
+                    "contact": "netork@localhost",
+                    "location": "Managed by netOrk",
+                    "sysobjid": "",
+                    "bindip": "",
+                }
+            })
+            lines.append("[config] SNMP enabled with community 'public'.")
+        except Exception as exc:
+            lines.append(f"[config] error: {exc}")
+
+        # 3. Start / restart the SNMP service
+        try:
+            self._post("/api/netsnmp/service/restart")
+            lines.append("[service] net-snmp restarted.")
+        except Exception:
+            try:
+                self._post("/api/netsnmp/service/start")
+                lines.append("[service] net-snmp started.")
+            except Exception as exc:
+                lines.append(f"[service] start failed: {exc}")
+
+        # 4. Verify
+        try:
+            cfg = self._get("/api/netsnmp/general/get")
+            general = cfg.get("general", cfg)
+            success = str(general.get("enabled", "0")) == "1" and bool(general.get("community"))
+        except Exception:
+            success = False
+
+        if success:
+            lines.append("[ok] SNMP is active with community 'public'.")
+        else:
+            lines.append("[warn] Could not verify SNMP state via API.")
+
+        return {"success": success, "output": "\n".join(lines)}