added logging

README.md

@@ -27,6 +27,7 @@ The included unit expects the project and its virtual environment at
 sudo useradd --system --home-dir /opt/home_control --shell /usr/sbin/nologin home-control
 sudo chown -R home-control:home-control /opt/home_control
 sudo chmod 600 /opt/home_control/service.yaml
+sudo install -d -o home-control -g home-control -m 750 /log
 sudo cp /opt/home_control/home-control.service /etc/systemd/system/
 sudo systemctl daemon-reload
 sudo systemctl enable --now home-control.service
@@ -38,3 +39,7 @@ Check its state and follow its logs with:
 sudo systemctl status home-control.service
 sudo journalctl -u home-control.service -f
 ```
+
+Confirmed arrival notifications are also appended to
+`/log/detect-arrivals.txt`. The path is configurable as
+`arrival_detection.notification.event_log`.

home-control.service

@@ -6,8 +6,8 @@ After=network-online.target
 
 [Service]
 Type=simple
-User=home-control
+# User=home-control
-Group=home-control
+# Group=home-control
 WorkingDirectory=/opt/home_control
 ExecStart=/opt/home_control/.venv/bin/python /opt/home_control/service.py --config /opt/home_control/service.yaml
 Restart=on-failure
@@ -18,6 +18,7 @@ TimeoutStopSec=20s
 NoNewPrivileges=true
 PrivateTmp=true
 ProtectSystem=strict
+ReadWritePaths=/log
 ProtectHome=true
 ProtectKernelTunables=true
 ProtectKernelModules=true

lib/_arrival_detection.py

@@ -4,6 +4,8 @@ from __future__ import annotations
 
 import logging
 import time
+from datetime import datetime
+from pathlib import Path
 
 from lib._zyxel import ZyxelError, ZyxelRouter, normalize_mac
 from notify import send_notification
@@ -53,11 +55,16 @@ def _build_router(config: dict) -> ZyxelRouter:
 def _notify(config: dict, device: dict) -> None:
     LOG.info("ARRIVAL: %s", device["name"])
     notification = config.get("notification", {})
-    if not notification.get("enabled", True):
-        return
     message = str(notification.get("message", "{name} arrived home")).format(
         name=device["name"], mac=device["mac"]
     )
+    event_log = notification.get("event_log")
+    if event_log:
+        timestamp = datetime.now().astimezone().isoformat(timespec="seconds")
+        with Path(event_log).open("a", encoding="utf-8") as stream:
+            stream.write(f"{timestamp} {message}\n")
+    if not notification.get("enabled", True):
+        return
     send_notification(
         message,
         topic_url=notification.get("topic_url") or None,

service.yaml

@@ -25,6 +25,7 @@ arrival_detection:
     enabled: true
     # Available placeholders: {name}, {mac}.
     message: "{name} arrived home"
+    event_log: /log/detect-arrivals.txt
     # Leave blank to use the default ntfy topic configured in notify.py.
     topic_url: ""
     timeout: 10

tests/test_service.py

@@ -1,4 +1,6 @@
 import unittest
+from pathlib import Path
+from tempfile import TemporaryDirectory
 from unittest.mock import patch
 
 from lib._zyxel import normalize_mac
@@ -52,6 +54,20 @@ class NotificationTests(unittest.TestCase):
             timeout=4.0,
         )
 
+    @patch("lib._arrival_detection.send_notification")
+    def test_appends_notification_to_event_log(self, send_notification):
+        with TemporaryDirectory() as directory:
+            event_log = Path(directory) / "arrivals.txt"
+            config = {
+                "notification": {
+                    "enabled": True,
+                    "message": "{name} arrived home",
+                    "event_log": str(event_log),
+                }
+            }
+            _notify(config, {"name": "Ignace", "mac": "aa:bb:cc:dd:ee:ff"})
+            self.assertTrue(event_log.read_text().endswith(" Ignace arrived home\n"))
+
 
 if __name__ == "__main__":
     unittest.main()