adds mqtt.sh sample script

sensors/mqtt.sh

@@ -0,0 +1,94 @@
+#!/bin/bash
+
+# MQTT configuration attributes
+# https://www.home-assistant.io/integrations/sensor.mqtt/
+# https://www.home-assistant.io/integrations/switch.mqtt/
+
+# Explanation
+# https://www.youtube.com/watch?v=VHiCtZqllU8
+# https://resinchemtech.blogspot.com/2023/12/mqtt-auto-discovery.html
+
+# Prerequesite
+#apt install mosquitto-clients
+
+MQTT_BROKER="hass.lan"
+MQTT_PORT=1883
+MQTT_USERNAME="pve"
+MQTT_PASSWORD="TeLEARDHemAS"
+
+
+NAME="Host $(hostname -s)"
+ID="host_$(hostname -s)"
+TOPIC="host/$(hostname -s)"
+
+DEVICE_CLASS="power"
+UNIT="W"
+ICON="mdi:lightning-bolt"
+MANUFACTURER="custom"
+MODEL="custom"
+EXPIRE_AFTER_S="90"
+
+MQTT_CONFIG_TOPIC="homeassistant/sensor/${ID}/config"
+MQTT_STATE_TOPIC="${TOPIC}/${DEVICE_CLASS}"
+
+function send {
+    TOPIC=$1
+    PAYLOAD=$2
+    echo "Sending payload to ${MQTT_BROKER}:${MQTT_PORT}/${TOPIC} ..."
+    echo "$1"
+    mosquitto_pub -h "${MQTT_BROKER}" -p "${MQTT_PORT}" -u "${MQTT_USERNAME}" -P "${MQTT_PASSWORD}" \
+        -t "$TOPIC" \
+        -m "$PAYLOAD"
+}
+
+function config {
+    send "${MQTT_CONFIG_TOPIC}" "$1"
+}
+
+function state {
+    send "${MQTT_STATE_TOPIC}" "$1"
+}
+
+function setupEntity {
+    config "{\
+\"name\": \"${DEVICE_CLASS}\",\
+\"unique_id\": \"${ID}_${DEVICE_CLASS}\",\
+\"device_class\": \"${DEVICE_CLASS}\",\
+\"unit_of_measurement\": \"${UNIT}\",\
+\"state_topic\": \"${MQTT_STATE_TOPIC}\",\
+\"expire_after\": \"${EXPIRE_AFTER_S}\",\
+\"icon\": \"${ICON}\",\
+\"device\": {\
+\"name\": \"${NAME}\",\
+\"identifiers\": \"${ID}\",\
+\"manufacturer\": \"${MANUFACTURER}\",\
+\"model\": \"${MODEL}\"\
+}}"
+
+#\"firendly_name\": \"${NAME} power\",\
+#    "hw_version":"1.02",
+#     "sw_version":"2.45",
+#     "configuration_url":"http://192.168.1.226"
+}
+
+function deleteEntity {
+    config ""
+}
+
+if [ "$1" == "r" ]; then
+    deleteEntity
+    exit 0 
+fi
+
+if [ -n "$1" ]; then
+    setupEntity
+    state "$1"
+    exit 0 
+fi
+
+if [ -z "$1" ]; then
+    setupEntity
+    exit 0
+fi
+
+exit 1