Add timezone display for snapshot time, change history default to unlimited

Snapshot time hint now shows the server timezone and warns if the
browser timezone differs. History days default changed from 7 to 0
(keep all snapshots) so users don't lose data unexpectedly. All
docker-compose examples include a commented TZ environment variable.

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

Author: itsDNNS

INSTALL.md

@@ -97,6 +97,8 @@ services:
       - "8765:8765"
     volumes:
       - docsight_data:/data
+    # environment:
+    #   - TZ=Europe/Berlin  # set container timezone for snapshot scheduling
 
 volumes:
   docsight_data:
@@ -146,6 +148,8 @@ services:
       - "8765:8765"
     volumes:
       - docsight_data:/data
+    # environment:
+    #   - TZ=Europe/Berlin  # set container timezone for snapshot scheduling
 
 volumes:
   docsight_data:
@@ -187,6 +191,8 @@ services:
       - "8765:8765"
     volumes:
       - docsight_data:/data
+    # environment:
+    #   - TZ=Europe/Berlin  # set container timezone for snapshot scheduling
 
 volumes:
   docsight_data:
@@ -244,8 +250,8 @@ Click **Test Connection** to verify DOCSight can reach your router. If successfu
 |---|---|---|
 | **ISP** | Your internet provider name (for reports) | - |
 | **Poll Interval** | How often to read channel data (seconds) | `300` (5 min) |
-| **History Days** | How many days of snapshots to keep | `7` |
-| **Snapshot Time** | When to save the daily snapshot | `03:00` |
+| **History Days** | How many days of snapshots to keep (0 = unlimited) | `0` (keep all) |
+| **Snapshot Time** | When to save the daily snapshot (server timezone, set `TZ` env var to change) | `06:00` |
 
 ### Advanced: MQTT for Home Assistant (optional)
 

README.md

@@ -83,7 +83,7 @@ Copy `.env.example` to `.env` and edit:
 | `MQTT_TOPIC_PREFIX` | `docsight` | MQTT topic prefix |
 | `POLL_INTERVAL` | `300` | Polling interval in seconds |
 | `WEB_PORT` | `8765` | Web UI port |
-| `HISTORY_DAYS` | `7` | Snapshot retention in days |
+| `HISTORY_DAYS` | `0` | Snapshot retention in days (0 = unlimited) |
 | `ADMIN_PASSWORD` | - | Web UI password (optional) |
 
 </details>

app/config.py

@@ -28,7 +28,7 @@
     "mqtt_topic_prefix": "docsight",
     "poll_interval": 300,
     "web_port": 8765,
-    "history_days": 7,
+    "history_days": 0,
     "snapshot_time": "06:00",
     "theme": "dark",
     "language": "en",

app/i18n.py

@@ -112,9 +112,10 @@
     "poll_interval": "Poll Interval",
     "interval_sec": "Interval (seconds)",
     "history_days": "History (days)",
-    "history_hint": "How long snapshots are stored",
+    "history_hint": "0 = keep all snapshots",
     "snapshot_time": "Daily Snapshot (time)",
     "snapshot_hint": "Reference time for daily comparisons and trends",
+    "snapshot_browser_tz": "Your timezone",
     "advanced_mqtt": "Advanced: MQTT / Home Assistant",
     "optional": "Optional",
     "mqtt_broker": "MQTT Broker",
@@ -273,9 +274,10 @@
     "poll_interval": "Abfrageintervall",
     "interval_sec": "Intervall (Sekunden)",
     "history_days": "Historie (Tage)",
-    "history_hint": "Wie lange Snapshots gespeichert werden",
+    "history_hint": "0 = alle Snapshots behalten",
     "snapshot_time": "Tages-Snapshot (Uhrzeit)",
     "snapshot_hint": "Referenz-Zeitpunkt fuer Tagesvergleiche und Trends",
+    "snapshot_browser_tz": "Deine Zeitzone",
     "advanced_mqtt": "Erweitert: MQTT / Home Assistant",
     "optional": "Optional",
     "mqtt_broker": "MQTT Broker",

app/storage.py

@@ -141,7 +141,9 @@ def get_intraday_data(self, date):
         return results
 
     def _cleanup(self):
-        """Delete snapshots older than max_days."""
+        """Delete snapshots older than max_days. 0 = keep all."""
+        if self.max_days <= 0:
+            return
         cutoff = (datetime.now() - timedelta(days=self.max_days)).strftime(
             "%Y-%m-%dT%H:%M:%S"
         )

app/templates/settings.html

@@ -233,12 +233,13 @@ <h2>{{ t.general }}</h2>
             </div>
             <div class="form-row">
                 <label for="history_days">{{ t.history_days }}</label>
-                <input type="number" id="history_days" name="history_days" value="{{ config.history_days }}" min="1">
+                <input type="number" id="history_days" name="history_days" value="{{ config.history_days }}" min="0">
+                <span class="hint">{{ t.history_hint }}</span>
             </div>
             <div class="form-row">
                 <label for="snapshot_time">{{ t.snapshot_time }}</label>
                 <input type="time" id="snapshot_time" name="snapshot_time" value="{{ config.snapshot_time }}">
-                <span class="hint">{{ t.snapshot_hint }}</span>
+                <span class="hint" id="snapshot-tz-hint">{{ t.snapshot_hint }} ({{ server_tz }})</span>
             </div>
             <div class="form-row">
                 <label for="language">{{ t.language }}</label>
@@ -398,6 +399,15 @@ <h2>{{ t.general }}</h2>
         errEl.style.display = 'block';
     });
 });
+
+(function() {
+    var serverTz = '{{ server_tz }}';
+    var browserTz = Intl.DateTimeFormat().resolvedOptions().timeZone;
+    if (browserTz && browserTz !== serverTz) {
+        var el = document.getElementById('snapshot-tz-hint');
+        el.textContent = el.textContent + ' — ' + T.snapshot_browser_tz + ': ' + browserTz;
+    }
+})();
 </script>
 
 </body>

app/templates/setup.html

@@ -246,13 +246,13 @@ <h2><span class="step-num">2</span>{{ t.general }}</h2>
             </div>
             <div class="form-row">
                 <label for="history_days">{{ t.history_days }}</label>
-                <input type="number" id="history_days" name="history_days" value="{{ config.history_days }}" min="1" max="90">
+                <input type="number" id="history_days" name="history_days" value="{{ config.history_days }}" min="0" max="3650">
                 <span class="hint">{{ t.history_hint }}</span>
             </div>
             <div class="form-row">
                 <label for="snapshot_time">{{ t.snapshot_time }}</label>
                 <input type="time" id="snapshot_time" name="snapshot_time" value="{{ config.snapshot_time }}">
-                <span class="hint">{{ t.snapshot_hint }}</span>
+                <span class="hint" id="snapshot-tz-hint">{{ t.snapshot_hint }} ({{ server_tz }})</span>
             </div>
         </div>
     </div>
@@ -428,6 +428,15 @@ <h2>{{ t.mqtt_broker }}</h2>
         errEl.style.display = 'block';
     });
 });
+
+(function() {
+    var serverTz = '{{ server_tz }}';
+    var browserTz = Intl.DateTimeFormat().resolvedOptions().timeZone;
+    if (browserTz && browserTz !== serverTz) {
+        var el = document.getElementById('snapshot-tz-hint');
+        el.textContent = el.textContent + ' — ' + T.snapshot_browser_tz + ': ' + browserTz;
+    }
+})();
 </script>
 
 </body>

app/web.py

@@ -14,6 +14,10 @@
 from .config import POLL_MIN, POLL_MAX, PASSWORD_MASK, SECRET_KEYS
 from .i18n import get_translations, LANGUAGES
 
+def _server_timezone():
+    """Return the server's current timezone abbreviation (e.g. 'UTC', 'CET')."""
+    return datetime.now().astimezone().strftime("%Z") or time.tzname[0] or "UTC"
+
 log = logging.getLogger("docsis.web")
 
 app = Flask(__name__, template_folder="templates")
@@ -216,7 +220,7 @@ def setup():
     config = _config_manager.get_all(mask_secrets=True) if _config_manager else {}
     lang = _get_lang()
     t = get_translations(lang)
-    return render_template("setup.html", config=config, poll_min=POLL_MIN, poll_max=POLL_MAX, t=t, lang=lang, languages=LANGUAGES)
+    return render_template("setup.html", config=config, poll_min=POLL_MIN, poll_max=POLL_MAX, t=t, lang=lang, languages=LANGUAGES, server_tz=_server_timezone())
 
 
 @app.route("/settings")
@@ -226,7 +230,7 @@ def settings():
     theme = _config_manager.get_theme() if _config_manager else "dark"
     lang = _get_lang()
     t = get_translations(lang)
-    return render_template("settings.html", config=config, theme=theme, poll_min=POLL_MIN, poll_max=POLL_MAX, t=t, lang=lang, languages=LANGUAGES)
+    return render_template("settings.html", config=config, theme=theme, poll_min=POLL_MIN, poll_max=POLL_MAX, t=t, lang=lang, languages=LANGUAGES, server_tz=_server_timezone())
 
 
 @app.route("/api/config", methods=["POST"])

docker-compose.yml

@@ -7,6 +7,8 @@ services:
       - "8765:8765"
     volumes:
       - docsight_data:/data
+    # environment:
+    #   - TZ=Europe/Berlin  # set container timezone for snapshot scheduling
     # env_file: .env  # uncomment if using environment variables
 
 volumes:

tests/test_storage.py

@@ -56,3 +56,11 @@ def test_intraday_data(self, storage, sample_analysis):
     def test_empty_storage(self, storage):
         assert storage.get_snapshot_list() == []
         assert storage.get_dates_with_data() == []
+
+    def test_unlimited_retention(self, tmp_path, sample_analysis):
+        """max_days=0 should keep all snapshots (no cleanup)."""
+        db_path = str(tmp_path / "unlimited.db")
+        s = SnapshotStorage(db_path, max_days=0)
+        s.save_snapshot(sample_analysis)
+        s.save_snapshot(sample_analysis)
+        assert len(s.get_snapshot_list()) == 2