From 0f973457a414b4541bc8f6a5175b1be399c3e06b Mon Sep 17 00:00:00 2001
From: Mika <kontakt@donau2space.de>
Date: Sun, 26 Apr 2026 02:07:50 +0000
Subject: [PATCH] Add data_logging/src/data_logging/core.py

---
 data_logging/src/data_logging/core.py | 81 +++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 data_logging/src/data_logging/core.py

diff --git a/data_logging/src/data_logging/core.py b/data_logging/src/data_logging/core.py
new file mode 100644
index 0000000..fe00440
--- /dev/null
+++ b/data_logging/src/data_logging/core.py
@@ -0,0 +1,81 @@
+import json
+from dataclasses import dataclass, asdict
+from pathlib import Path
+from typing import Any
+from datetime import datetime
+import logging
+
+
+__all__ = ["LogEntry", "log_wifi_data"]
+
+
+logging.basicConfig(
+    level=logging.INFO,
+    format="%(asctime)s [%(levelname)s] %(message)s",
+)
+
+
+@dataclass
+class LogEntry:
+    """Repräsentiert einen WLAN-Messdatensatz für Logging-Zwecke."""
+    timestamp: str
+    frequency: float
+    signal_strength: float
+
+    def validate(self) -> None:
+        """Validiert die Felder des LogEntries."""
+        try:
+            datetime.fromisoformat(self.timestamp)
+        except ValueError as e:
+            raise ValueError(f"Ungültiger Zeitstempel: {self.timestamp}") from e
+
+        if not isinstance(self.frequency, (float, int)):
+            raise TypeError("frequency muss float oder int sein")
+        if not isinstance(self.signal_strength, (float, int)):
+            raise TypeError("signal_strength muss float oder int sein")
+
+
+def log_wifi_data(timestamp: str, frequency: float, signal_strength: float, output_path: str = "output/wifi_log.json") -> None:
+    """Protokolliert einzelne WLAN-Signalmessdaten in einer JSON-Datei.
+
+    Args:
+        timestamp: Zeitstempel im ISO 8601-Format.
+        frequency: Frequenz in GHz.
+        signal_strength: Signalstärke in dBm.
+        output_path: Pfad zur Logdatei.
+    """
+
+    logging.debug("Initialisiere Logeintrag für WLAN-Daten.")
+
+    entry = LogEntry(timestamp=timestamp, frequency=frequency, signal_strength=signal_strength)
+    entry.validate()
+
+    path = Path(output_path)
+    path.parent.mkdir(parents=True, exist_ok=True)
+
+    # Bestehende Daten laden, falls vorhanden
+    if path.exists():
+        try:
+            with path.open("r", encoding="utf-8") as f:
+                data = json.load(f)
+                if not isinstance(data, list):
+                    logging.warning("Unerwartetes Format in Logdatei, erstelle neue Liste.")
+                    data = []
+        except (json.JSONDecodeError, OSError) as e:
+            logging.error(f"Fehler beim Lesen der Logdatei: {e}")
+            data = []
+    else:
+        data = []
+
+    data.append(asdict(entry))
+
+    # Validierung der Ausgabe
+    assert all(set(LogEntry.__annotations__.keys()) <= set(d.keys()) for d in data), "Logdatei enthält ungültige Felder"
+
+    try:
+        with path.open("w", encoding="utf-8") as f:
+            json.dump(data, f, indent=2, ensure_ascii=False)
+        logging.info(f"Eintrag erfolgreich protokolliert: {path}")
+    except OSError as e:
+        logging.error(f"Fehler beim Schreiben in die Datei: {e}")
+        raise
\ No newline at end of file