add time remaining calculation

README.md

@@ -35,6 +35,7 @@ services:
     - INTERVAL=60
     - MONITORED_CONDITIONS=status,capacity
     - BATTERY_HEALTH=1
+    - TIME_REMAINING=1
     volumes:
     - /sys/class/power_supply:/sys/class/power_supply:ro
     restart: unless-stopped
@@ -59,8 +60,10 @@ You can specify only those conditions that you'd like to track. The default is t
 ```
 alarm,capacity,capacity_level,present,status,voltage_now
 ```
-# Battery health calculation
-The default is to also provide a battery health percentage calculation by dividing `energy_full` by `energy_full_design`. This can be disabled by setting `BATTERY_HEALTH` to `0` in your `docker-compose.yaml`.
+
+# Battery health and time remaining calculations
+The default is to also provide a battery health percentage calculation by dividing `energy_full` by `energy_full_design`. This can be disabled by setting `BATTERY_HEALTH` to `0` in your `docker-compose.yaml`. 
+Similiarly, an estimate of time remaining on battery (in hours) is calculated by dividing `energy_now` by `power_now`. This can be disabled by setting `TIME_REMAINING` to `0` in your `docker-compose.yaml`.
 
 # Example Home Assistant configuration
 ```yaml

battery2mqtt.py

@@ -12,6 +12,7 @@ MQTT_TOPIC = os.getenv('MQTT_TOPIC', 'server')
 INTERVAL = int(os.getenv('INTERVAL', 60))
 MONITORED_CONDITIONS = os.environ.get('MONITORED_CONDITIONS','alarm,capacity,capacity_level,present,status,voltage_now')
 BATTERY_HEALTH = os.getenv('BATTERY_HEALTH', 1)
+TIME_REMAINING = os.getenv('TIME_REMAINING', 1)
 
 client = mqtt.Client("battery2mqtt")
 client.username_pw_set(MQTT_USER, MQTT_PASSWORD)
@@ -24,6 +25,7 @@ dirs = os.listdir(path)
 
 payload = {}
 health_calc = {}
+time_remaining = {}
 
 while True:
     for dir in dirs:
@@ -44,10 +46,18 @@ while True:
                 for name in ['energy_full_design', 'energy_full']:
                     with open(path + dir + '/' + name, 'r') as file:
                         health_calc[name] = int(file.read().replace('\n',''))
-                json.dumps(health_calc)
                 payload['battery_health'] = round((health_calc['energy_full'] / health_calc['energy_full_design']) * 100,2)
             except:
                 pass
+        
+        if TIME_REMAINING == '1':
+            try:
+                for name in ['energy_now', 'power_now']:
+                    with open(path + dir + '/' + name, 'r') as file:
+                        time_remaining[name] = int(file.read().replace('\n',''))
+                payload['time_remaining'] = round((time_remaining['energy_now'] / time_remaining['power_now']),2)
+            except:
+                pass
 
     client.connect(MQTT_HOST)
     client.publish("battery2mqtt/" + MQTT_TOPIC + '/' + dir, json.dumps(payload), qos=MQTT_QOS, retain=False)