Esphome (#50)

* feat: add ESPHome support

Author: kpetremann

README.md

@@ -71,13 +71,25 @@ mqtt_zigbee_availability{topic="zigbee2mqtt_garage"} 1.0
 mqtt_temperature{topic="zigbee2mqtt_garage"} 1.0
 ```
 
-Note: the metric name mqtt_state is not kept to reduce collision risks as it is too common.
+Note: the metric name mqtt_state is not kept reducing collision risks as it is too common.
 
 ### Zwavejs2Mqtt
 
 This exporter also supports Zwavejs2Mqtt metrics, preferably using "named topics" (see [official documentation](https://zwave-js.github.io/zwavejs2mqtt/#/usage/setup?id=gateway)).
 
-To setup this, you need to specify the topic prefix used by Zwavejs2Mqtt in `ZWAVE_TOPIC_PREFIX` the environment variable (default being "zwave/").
+To set up this, you need to specify the topic prefix used by Zwavejs2Mqtt in `ZWAVE_TOPIC_PREFIX` the environment variable (default being "zwave/").
+
+### ESPHome
+
+ESPHome is supported only when using the default `state_topic`: "<TOPIC_PREFIX>/<COMPONENT_TYPE>/<COMPONENT_NAME>/state". (see [official documentation](https://esphome.io/components/mqtt.html#mqtt-component-base-configuration)).
+
+To set up this, you need to specify the topic prefix list used by ESPHome in `ESPHOME_TOPIC_PREFIXES` the environment variable (default being "", so disabled).
+
+This is a list so you can simply set one or more topic prefixes, the separator being a comma.
+
+Example: `ESPHOME_TOPIC_PREFIXES="esphome-weather-indoor,esphome-weather-outdoor"`
+
+If all of your ESPHome topics share a same prefix, you can simply put the common part. In the above example, `"esphome"` will match all topic starting by "esphome".
 
 ### Configuration
 
@@ -102,6 +114,7 @@ The list of parameters are:
   * `TOPIC_LABEL`: Define the Prometheus label for the topic, example temperature{topic="device1"} (default: topic)
   * `ZIGBEE2MQTT_AVAILABILITY`: Normalize sensor name for device availability metric added by Zigbee2MQTT (default: False)
   * `ZWAVE_TOPIC_PREFIX`: MQTT topic used for Zwavejs2Mqtt messages (default: zwave/)
+  * `ESPHOME_TOPIC_PREFIXES`: MQTT topic used for Zwavejs2Mqtt messages (default: "")
 
 ### Deployment
 

mqtt_exporter/main.py

@@ -209,6 +209,30 @@ def _normalize_zwave2mqtt_format(topic, payload):
     return topic, payload_dict
 
 
+def _normalize_esphome_format(topic, payload):
+    """Normalize esphome format.
+
+    Example:
+    esphome/sensor/temperature/state
+
+    Only supports default state_topic:
+    <topic_prefix>/<component_type>/<component_name>/state
+    """
+    info = topic.split("/")
+
+    topic = f"{info[0].lower()}/{info[1].lower()}"
+    payload_dict = {info[-2]: payload}
+    return topic, payload_dict
+
+
+def _is_esphome_topic(topic):
+    for prefix in settings.ESPHOME_TOPIC_PREFIXES:
+        if prefix and topic.startswith(prefix):
+            return True
+
+    return False
+
+
 def _parse_message(raw_topic, raw_payload):
     """Parse topic and payload to have exposable information."""
     # parse MQTT payload
@@ -223,6 +247,8 @@ def _parse_message(raw_topic, raw_payload):
 
     if raw_topic.startswith(settings.ZWAVE_TOPIC_PREFIX):
         topic, payload = _normalize_zwave2mqtt_format(raw_topic, payload)
+    elif _is_esphome_topic(raw_topic):
+        topic, payload = _normalize_esphome_format(raw_topic, payload)
     elif not isinstance(payload, dict):
         topic, payload = _normalize_name_in_topic_msg(raw_topic, payload)
     else:

mqtt_exporter/settings.py

@@ -6,6 +6,7 @@
 TOPIC = os.getenv("MQTT_TOPIC", "#")
 IGNORED_TOPICS = os.getenv("MQTT_IGNORED_TOPICS", "").split(",")
 ZWAVE_TOPIC_PREFIX = os.getenv("ZWAVE_TOPIC_PREFIX", "zwave/")
+ESPHOME_TOPIC_PREFIXES = os.getenv("ESPHOME_TOPIC_PREFIXES", "").split(",")
 
 ZIGBEE2MQTT_AVAILABILITY = os.getenv("ZIGBEE2MQTT_AVAILABILITY", "False") == "True"
 LOG_LEVEL = os.getenv("LOG_LEVEL", "INFO")

tests/functional/test_parse_message.py

@@ -140,3 +140,26 @@ def test_parse_message__zwave_js__payload_not_dict():
     parsed_topic, parsed_payload = _parse_message(topic, payload)
     assert parsed_topic == "zwave_BackRoom_Multisensor_sensor_multilevel_endpoint_0_Air_temperature"
     assert parsed_payload == {}
+
+
+def test__parse_message__esphome_style():
+    """Test message parsing with espthome style.
+
+    Same format for SONOFF sensors.
+    """
+    settings.ESPHOME_TOPIC_PREFIXES = ["esp", "ESP"]
+    topic = "esphome/outdoor/sensor/temperature/state"
+    payload = "20.0"
+
+    parsed_topic, parsed_payload = _parse_message(topic, payload)
+
+    assert parsed_topic == "esphome_outdoor"
+    assert parsed_payload == {"temperature": 20.0}
+
+    topic = "ESPHOME/indoor/sensor/temperature/state"
+    payload = "22.0"
+
+    parsed_topic, parsed_payload = _parse_message(topic, payload)
+
+    assert parsed_topic == "esphome_indoor"
+    assert parsed_payload == {"temperature": 22.0}