Initial commit: LAN Checker

Network health monitoring script with MQTT reporting for Home Assistant.
- Ping, HTTP, and SNMP checkers
- MQTT Discovery for automatic entity creation
- Configurable check intervals

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

checkers/ping.py

@@ -0,0 +1,53 @@
+import subprocess
+import time
+import platform
+
+from .base import BaseChecker, CheckResult
+
+
+class PingChecker(BaseChecker):
+    def check(self) -> CheckResult:
+        host = self.config["host"]
+        count = self.config.get("count", 1)
+        timeout = self.config.get("timeout", 5)
+
+        # Adapt ping command for OS
+        if platform.system().lower() == "windows":
+            cmd = ["ping", "-n", str(count), "-w", str(timeout * 1000), host]
+        else:
+            cmd = ["ping", "-c", str(count), "-W", str(timeout), host]
+
+        start = time.time()
+        try:
+            result = subprocess.run(
+                cmd,
+                capture_output=True,
+                text=True,
+                timeout=timeout + 5
+            )
+            response_time = (time.time() - start) * 1000  # ms
+
+            if result.returncode == 0:
+                return CheckResult(
+                    success=True,
+                    message="Host is reachable",
+                    response_time=response_time
+                )
+            else:
+                return CheckResult(
+                    success=False,
+                    message="Host is unreachable",
+                    response_time=None
+                )
+        except subprocess.TimeoutExpired:
+            return CheckResult(
+                success=False,
+                message="Ping timeout",
+                response_time=None
+            )
+        except Exception as e:
+            return CheckResult(
+                success=False,
+                message=f"Ping error: {e}",
+                response_time=None
+            )