doorbell: fake zigbee probe device + E2E validation (no real ring)

infra/doorbell-probe/fake-device.py

@@ -0,0 +1,63 @@
+#!/usr/bin/env python3
+# /// script
+# requires-python = ">=3.10"
+# dependencies = [
+#     "paho-mqtt>=2.0",
+# ]
+# ///
+"""Fake Zigbee device for doorbell E2E validation.
+
+Subscribes to a "set" topic and echoes a TOGGLE back to a "state" topic
+(retained), emulating a Zigbee smart plug at the MQTT layer. This lets the
+doorbell E2E probe confirm the full chain (ntfy.sh -> listener -> MQTT -> device)
+without toggling a real lamp.
+
+Env vars:
+    MQTT_HOST     default "mosquitto"
+    MQTT_PORT     default 1883
+    SET_TOPIC     default "zigbee2mqtt/DoorbellProbe/set"
+    STATE_TOPIC   default "zigbee2mqtt/DoorbellProbe"
+"""
+import json
+import os
+
+import paho.mqtt.client as mqtt
+
+MQTT_HOST = os.environ.get("MQTT_HOST", "mosquitto")
+MQTT_PORT = int(os.environ.get("MQTT_PORT", "1883"))
+SET_TOPIC = os.environ.get("SET_TOPIC", "zigbee2mqtt/DoorbellProbe/set")
+STATE_TOPIC = os.environ.get("STATE_TOPIC", "zigbee2mqtt/DoorbellProbe")
+
+
+def log(msg: str) -> None:
+    print(msg, flush=True)
+
+
+def on_connect(client, userdata, flags, reason_code, properties=None):
+    log(f"connected to {MQTT_HOST}:{MQTT_PORT} (rc={reason_code})")
+    client.subscribe(SET_TOPIC)
+
+
+def on_message(client, userdata, msg):
+    log(f"echo -> {STATE_TOPIC} (from {msg.topic})")
+    client.publish(STATE_TOPIC, json.dumps({"state": "TOGGLE", "echo": True}), retain=True)
+
+
+def main() -> None:
+    log(f"fake-device: {SET_TOPIC} -> {STATE_TOPIC}")
+    client = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2)
+    client.on_connect = on_connect
+    client.on_message = on_message
+    while True:
+        try:
+            client.connect(MQTT_HOST, MQTT_PORT, 60)
+            break
+        except Exception as e:
+            log(f"connect failed: {e}; retry in 5s")
+            import time
+            time.sleep(5)
+    client.loop_forever()
+
+
+if __name__ == "__main__":
+    main()