feat: web dashboard for live device data

Small companion service that receives SNEK callbacks, decodes Sens'it Discovery payloads for all 6 modes (Standby, Temperature, Light, Door, Vibration, Magnet), stores in SQLite, and serves a responsive dashboard. Backend (Python Flask): - POST /webhook: receive SNEK callback - GET /api/devices, /api/messages, /api/decode - GET /events: Server-Sent Events for live push - SQLite persistence at /data/messages.db Frontend: - Tailwind CSS via CDN, Chart.js for temp/humidity graph - Live updates via SSE - Device cards with icons per mode - Message log with human-readable summaries Deploy: - Separate deployment (snek-dashboard) with own PVC - LoadBalancer on 192.168.1.213:80 - SNEK callback URL: http://snek-dashboard.snek.svc.cluster.local/webhook Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-07-03 17:43:11 +02:00
parent c7ab02cc59
commit a77776d6d8
6 changed files with 570 additions and 0 deletions
@@ -0,0 +1,86 @@
+"""Sens'it Discovery payload decoder — all 6 modes."""
+
+MODES = {
+    0: "Standby / Button",
+    1: "Temperature",
+    2: "Light",
+    3: "Door",
+    4: "Vibration",
+    5: "Magnet",
+}
+
+
+def decode(payload_hex: str) -> dict:
+    """
+    Decode a 4-byte Sens'it Discovery payload.
+
+    Format (per Sens'it Discovery v3.1.0+ spec):
+        Byte 0: bits 7-3 = battery level, bits 2-0 = reserved (0b110)
+        Byte 1: bits 7-3 = mode, bits 2-1 = mode-specific / spare, bit 0 = button flag
+        Byte 2-3: mode-specific data
+
+    Battery formula: V = (raw × 0.05) + 2.7
+    """
+    payload_hex = payload_hex.strip().lower().replace("0x", "").replace(" ", "")
+    if len(payload_hex) != 8:
+        return {"error": f"payload must be 4 bytes (8 hex chars), got '{payload_hex}'"}
+
+    try:
+        b0, b1, b2, b3 = (int(payload_hex[i : i + 2], 16) for i in range(0, 8, 2))
+    except ValueError as e:
+        return {"error": str(e)}
+
+    # Common fields
+    battery_raw = (b0 >> 3) & 0x1F
+    battery_volts = round(battery_raw * 0.05 + 2.7, 2)
+    reserved = b0 & 0x07
+    mode = (b1 >> 3) & 0x1F
+    button_alert = bool(b1 & 0x01)
+
+    result = {
+        "raw": payload_hex,
+        "battery": battery_volts,
+        "battery_raw": battery_raw,
+        "reserved_ok": reserved == 0b110,
+        "mode": MODES.get(mode, f"Unknown ({mode})"),
+        "mode_id": mode,
+        "button_alert": button_alert,
+    }
+
+    # Mode-specific decoding
+    if mode == 1:  # Temperature
+        temp_msb = (b1 >> 2) & 0x01
+        temp_raw = (temp_msb << 8) | b2
+        result["temperature_c"] = round((temp_raw - 200) / 8, 2)
+        result["humidity_pct"] = round(b3 / 2, 1)
+
+    elif mode == 2:  # Light
+        brightness_msb = (b1 >> 2) & 0x01
+        brightness_raw = (brightness_msb << 8) | b2
+        result["brightness_lux"] = round(brightness_raw / 96, 2)
+
+    elif mode == 3:  # Door
+        door_status_bits = (b1 >> 1) & 0x03
+        door_map = {0: "closed", 1: "opened", 2: "opening_alert", 3: "closing_alert"}
+        result["door_status"] = door_map.get(door_status_bits, "unknown")
+        result["event_count"] = (b2 << 8) | b3
+
+    elif mode == 4:  # Vibration
+        vib_status_bits = (b1 >> 1) & 0x03
+        vib_map = {0: "no_vibration", 1: "vibration_detected"}
+        result["vibration_status"] = vib_map.get(vib_status_bits, "unknown")
+        result["event_count"] = (b2 << 8) | b3
+
+    elif mode == 5:  # Magnet
+        mag_status_bits = (b1 >> 1) & 0x03
+        mag_map = {0: "no_magnet", 1: "magnet_detected"}
+        result["magnet_status"] = mag_map.get(mag_status_bits, "unknown")
+        result["event_count"] = (b2 << 8) | b3
+
+    return result
+
+
+if __name__ == "__main__":
+    # Sanity checks with the payloads we captured
+    for h in ("b60dc86e", "a60dc271", "b6043081"):
+        print(h, "→", decode(h))