Add timestamp (with ntptime and RTC)

code/main.py

@@ -44,6 +44,15 @@ bme.set_measurement_settings({
 # Start the sensor automatically sensing
 bme.set_power_mode(bme280_i2c.BME280_NORMAL_MODE)
 
+# RTC setup
+rtc=machine.RTC()
+settime()
+
+
+def now():
+    """Return a string representing date/time now"""
+    return "{0:04d}/{1:02d}/{2:02d}_{4:02d}:{5:02d}:{6:02d}".format(*rtc.datetime())
+
 
 def MqttPublish(client, topic, message, retain=False, qos=0, sleep=10):
     """MQTT publish helper"""
@@ -61,6 +70,7 @@ client = MQTTClient(client_id=config.CLIENT_ID,
                     port=config.MQTT_PORT)
 client.connect()
 
+MqttPublish(client, "last_boot", now())
 MqttPublish(client, "location", config.LOCATION, retain=True, qos=1)
 MqttPublish(client, "humidity/unit", "%", retain=True)
 MqttPublish(client, "humidity/desc", "Capteur Bosch BME280", retain=True, qos=0)
@@ -86,7 +96,8 @@ topics = {"humidity" : ["humidity/value", "{:.0f}", 1, 1],
 
 while 1:
     bme_data = bme.get_measurement()
-    print(bme_data)
+    meas_time = now()
+    print(meas_time, ":", bme_data)
 
     for nature, param in topics.items():
         MqttPublish(client,
@@ -96,5 +107,6 @@ while 1:
                     sleep=50)
 
     MqttPublish(client, "wifi/rssi", "{:.0f}".format(wlan.status('rssi')))
+    MqttPublish(client, "time/last_values", meas_time, retain=True)
 
     time.sleep_ms(1000)