feat: add network scanner module with nmap discovery, config merge, and ping

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

backend/tests/test_network_scanner.py

@@ -0,0 +1,70 @@
+import pytest
+from unittest.mock import AsyncMock, MagicMock, patch
+from modules.network_scanner import NetworkScanner
+
+
+@pytest.fixture
+def scanner():
+    return NetworkScanner(subnet="192.168.1.0/24")
+
+
+def test_parse_scan_results(scanner):
+    mock_scan_result = {
+        "scan": {
+            "192.168.1.1": {
+                "status": {"state": "up"},
+                "hostnames": [{"name": "router.local", "type": "PTR"}],
+                "vendor": {"AA:BB:CC:DD:EE:FF": "Cisco"},
+            },
+            "192.168.1.10": {
+                "status": {"state": "up"},
+                "hostnames": [{"name": "", "type": ""}],
+                "vendor": {},
+            },
+        }
+    }
+
+    nodes = scanner.parse_scan_results(mock_scan_result)
+    assert len(nodes) == 2
+    assert nodes[0]["ip"] == "192.168.1.1"
+    assert nodes[0]["hostname"] == "router.local"
+    assert nodes[0]["status"] == "up"
+    assert nodes[1]["ip"] == "192.168.1.10"
+
+
+def test_merge_with_config(scanner):
+    discovered = [
+        {"ip": "192.168.1.1", "hostname": "router.local", "status": "up", "vendor": "Cisco"},
+        {"ip": "192.168.1.50", "hostname": "", "status": "up", "vendor": ""},
+    ]
+    configured = [
+        {
+            "name": "Router Principal",
+            "ip": "192.168.1.1",
+            "username": "admin",
+            "password": "pass",
+            "icon": "router",
+            "connections": [],
+        },
+    ]
+
+    merged = scanner.merge_with_config(discovered, configured)
+    # Router should have config data merged in
+    router = next(n for n in merged if n["ip"] == "192.168.1.1")
+    assert router["name"] == "Router Principal"
+    assert router["username"] == "admin"
+    assert router["status"] == "up"
+    # Unknown device keeps discovered data
+    unknown = next(n for n in merged if n["ip"] == "192.168.1.50")
+    assert unknown["name"] == "192.168.1.50"
+    assert unknown.get("username") is None
+
+
+@pytest.mark.asyncio
+async def test_ping_host(scanner):
+    with patch("asyncio.create_subprocess_exec", new_callable=AsyncMock) as mock_exec:
+        mock_proc = MagicMock()
+        mock_proc.wait = AsyncMock(return_value=0)
+        mock_exec.return_value = mock_proc
+        result = await scanner.ping_host("192.168.1.1")
+        assert result is True