added more diagnostics

meshtastic_receiver/CHANGELOG.md

@@ -7,5 +7,6 @@
 - Decrypts channel packets (AES-CTR) using the channel PSK.
 - Exposes the latest text message as a sensor (with from/to/time attributes).
 - Parses `LABEL:VALUE` messages into individual temperature/humidity sensors.
+- Link diagnostics per node: Last Seen, RSSI, SNR, and Hops Away.
 - Auto-creates entities via MQTT Discovery; resolves the HA broker through the
   Supervisor (no manual credentials required).

meshtastic_receiver/DOCS.md

@@ -7,6 +7,8 @@ the results in Home Assistant via MQTT Discovery:
   `to`, and timestamp as attributes).
 - **Parsed sensors** — values pulled out of structured messages such as
   `🏠 T1:20.8°C T2:26.7°C H1:83.7%` become individual numeric sensors.
+- **Link diagnostics** — `Last Seen`, `RSSI`, `SNR`, and `Hops Away`, derived
+  from each packet's metadata (shown under the device's Diagnostic section).
 
 This is the receiving counterpart to the **Meshtastic Sensor Broadcaster** add-on.
 
@@ -44,11 +46,23 @@ ignored). For example:
 produces `T1=20.8`, `T2=26.7`, `T3=26.6`, `H1=83.7`, `H2=54.4`, `H3=55.5`,
 each published to the sensor configured with that `label`.
 
+## Link diagnostics
+
+These are created automatically (no config) from each received packet:
+
+| Sensor | Source | Notes |
+|--------|--------|-------|
+| `Last Seen` | packet `rx_time` | Updates on every packet on the channel. |
+| `RSSI` | packet `rx_rssi` (dBm) | Signal at the gateway. Omitted when the gateway originated the packet (value 0). |
+| `SNR` | packet `rx_snr` (dB) | Published alongside RSSI. |
+| `Hops Away` | `hop_start - hop_limit` | Number of hops the packet traveled. Requires firmware that reports `hop_start`. |
+
 ## Topics used
 
 - Discovery: `{discovery_prefix}/sensor/{device}/{label}/config`
 - State: `meshtastic_receiver/{device}/{label}`
 - Last message: `meshtastic_receiver/{device}/last_message` (+ `/attributes`)
+- Diagnostics: `meshtastic_receiver/{device}/{last_seen,rssi,snr,hops_away}`
 - Availability: `meshtastic_receiver/{device}/status`
 
 ## Privacy note

meshtastic_receiver/receiver.py

@@ -14,6 +14,7 @@ import os
 import re
 import sys
 import time
+from datetime import datetime, timezone
 
 import paho.mqtt.client as mqtt
 import requests
@@ -62,6 +63,36 @@ CHANNEL_KEY = expand_psk(CHANNEL_PSK)
 # Matches "T1:20.8", "H2:54.4", "P:1013" etc. (unit suffix is ignored here).
 PAIR_RE = re.compile(r"([A-Za-z][A-Za-z0-9_]*)\s*:\s*(-?\d+(?:\.\d+)?)")
 
+# Built-in per-node diagnostic sensors derived from packet metadata.
+DIAGNOSTICS = [
+    {
+        "key": "last_seen",
+        "name": "Last Seen",
+        "device_class": "timestamp",
+        "icon": "mdi:clock-outline",
+    },
+    {
+        "key": "rssi",
+        "name": "RSSI",
+        "device_class": "signal_strength",
+        "unit": "dBm",
+        "state_class": "measurement",
+    },
+    {
+        "key": "snr",
+        "name": "SNR",
+        "unit": "dB",
+        "state_class": "measurement",
+        "icon": "mdi:signal",
+    },
+    {
+        "key": "hops_away",
+        "name": "Hops Away",
+        "state_class": "measurement",
+        "icon": "mdi:transit-connection-variant",
+    },
+]
+
 # Set once the HA broker client is connected.
 ha_client = None
 
@@ -158,10 +189,62 @@ def publish_discovery():
             json.dumps(cfg),
             retain=True,
         )
-    log(f"[ha] published discovery for last_message + {len(SENSORS)} sensors")
+
+    for d in DIAGNOSTICS:
+        key = d["key"]
+        cfg = {
+            "name": d["name"],
+            "unique_id": f"{DEVICE_UID}_{key}",
+            "state_topic": f"{BASE_TOPIC}/{key}",
+            "availability_topic": AVAIL_TOPIC,
+            "entity_category": "diagnostic",
+            "device": device_block(),
+        }
+        if d.get("unit"):
+            cfg["unit_of_measurement"] = d["unit"]
+        if d.get("device_class"):
+            cfg["device_class"] = d["device_class"]
+        if d.get("state_class"):
+            cfg["state_class"] = d["state_class"]
+        if d.get("icon"):
+            cfg["icon"] = d["icon"]
+        ha_client.publish(
+            f"{DISCOVERY_PREFIX}/sensor/{DEVICE_UID}/{key}/config",
+            json.dumps(cfg),
+            retain=True,
+        )
+
+    log(
+        f"[ha] published discovery for last_message + {len(SENSORS)} sensors "
+        f"+ {len(DIAGNOSTICS)} diagnostics"
+    )
 
 
 # --- Message handling --------------------------------------------------------
+def publish_metadata(mp):
+    """Publish link-quality diagnostics from a received MeshPacket."""
+    # Last seen: prefer the gateway's rx_time, fall back to now.
+    ts = (
+        datetime.fromtimestamp(mp.rx_time, tz=timezone.utc)
+        if mp.rx_time
+        else datetime.now(timezone.utc)
+    )
+    ha_client.publish(f"{BASE_TOPIC}/last_seen", ts.isoformat(), retain=True)
+
+    # RSSI/SNR are 0 for packets the gateway originated itself — only publish
+    # genuine over-the-air measurements.
+    if mp.rx_rssi != 0:
+        ha_client.publish(f"{BASE_TOPIC}/rssi", mp.rx_rssi, retain=True)
+        ha_client.publish(f"{BASE_TOPIC}/snr", round(mp.rx_snr, 2), retain=True)
+
+    # hop_start is the original TTL; hops taken = hop_start - hop_limit.
+    # hop_start == 0 means older firmware that didn't report it.
+    if mp.hop_start:
+        ha_client.publish(
+            f"{BASE_TOPIC}/hops_away", mp.hop_start - mp.hop_limit, retain=True
+        )
+
+
 def handle_text(text, from_id, to_id):
     # HA sensor states are limited to 255 chars.
     ha_client.publish(f"{BASE_TOPIC}/last_message", text[:255], retain=True)
@@ -212,6 +295,9 @@ def on_src_message(client, userdata, msg):
     mp = env.packet
     from_id = getattr(mp, "from")
 
+    # Link diagnostics + last-seen update for every packet on the channel.
+    publish_metadata(mp)
+
     if mp.HasField("decoded"):
         data = mp.decoded
     elif mp.HasField("encrypted"):