def get_last_measurement(self):
"""
Retrieve the latest sensor measurement from InfluxDB
:rtype: None
"""
self.last_measurement_success = False
# Get latest measurement (from within the past minute) from influxdb
try:
self.last_measurement = read_last_influxdb(
INFLUXDB_HOST,
INFLUXDB_PORT,
INFLUXDB_USER,
INFLUXDB_PASSWORD,
INFLUXDB_DATABASE,
self.sensor_id,
self.measure_type)
if self.last_measurement:
measurement_list = list(self.last_measurement.get_points(
measurement=self.measure_type))
self.last_time = measurement_list[0]['time']
self.last_measurement = measurement_list[0]['value']
utc_dt = datetime.strptime(self.last_time.split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
local_timestamp = str(datetime.fromtimestamp(utc_timestamp))
self.logger.debug("[PID {}] Latest {}: {} @ {}".format(
self.pid_id, self.measure_type,
self.last_measurement, local_timestamp))
self.last_measurement_success = True
else:
self.logger.warning("[PID {}] No data returned "
"from influxdb".format(self.pid_id))
except Exception as except_msg:
self.logger.exception("[PID {}] Failed to read "
"measurement from the influxdb "
"database: {}".format(self.pid_id,
except_msg))
def getLastMeasurement(self, measurement_type):
"""
Retrieve the latest sensor measurement
:return: The latest sensor value or None if no data available
:rtype: float or None
:param measurement_type: Environmental condition of a sensor (e.g.
temperature, humidity, pressure, etc.)
:type measurement_type: str
"""
last_measurement = read_last_influxdb(INFLUXDB_HOST,
INFLUXDB_PORT,
INFLUXDB_USER,
INFLUXDB_PASSWORD,
INFLUXDB_DATABASE,
self.sensor_id,
measurement_type).raw
if last_measurement:
number = len(last_measurement['series'][0]['values'])
last_value = last_measurement['series'][0]['values'][number-1][1]
return last_value
else:
return None
def get_lcd_strings(self):
"""
Retrieve measurements and/or timestamps and create strings for LCDs
If no data is retrieveable, create string "NO DATA RETURNED".
"""
# loop to acquire all measurements required to be displayed on the LCD
for i in range(1, self.lcd_y_lines+1):
if self.lcd_line[i]['id']:
# Get latest measurement (from within the past minute) from influxdb
# FROM '/.*/' returns any measurement (for grabbing time of last measurement)
last_measurement_success = False
try:
if self.lcd_line[i]['measurement'] == 'relay_state':
self.lcd_line[i]['measurement_value'] = self.relay_state(self.lcd_line[i]['id'])
last_measurement_success = True
else:
if self.lcd_line[i]['measurement'] == 'time':
last_measurement = read_last_influxdb(
INFLUXDB_HOST,
INFLUXDB_PORT,
INFLUXDB_USER,
INFLUXDB_PASSWORD,
INFLUXDB_DATABASE,
self.lcd_line[i]['id'],
'/.*/',
duration_min=5).raw
else:
last_measurement = read_last_influxdb(
INFLUXDB_HOST,
INFLUXDB_PORT,
INFLUXDB_USER,
INFLUXDB_PASSWORD,
INFLUXDB_DATABASE,
self.lcd_line[i]['id'],
self.lcd_line[i]['measurement'],
duration_min=5).raw
if last_measurement:
number = len(last_measurement['series'][0]['values'])
self.lcd_line[i]['time'] = last_measurement['series'][0]['values'][number-1][0]
self.lcd_line[i]['measurement_value'] = last_measurement['series'][0]['values'][number-1][1]
utc_dt = datetime.datetime.strptime(self.lcd_line[i]['time'].split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
local_timestamp = str(datetime.datetime.fromtimestamp(utc_timestamp))
self.logger.debug("[LCD {}] Latest {}: {} @ {}".format(
self.lcd_id, self.lcd_line[i]['measurement'],
self.lcd_line[i]['measurement_value'], local_timestamp))
last_measurement_success = True
else:
self.lcd_line[i]['time'] = None
self.lcd_line[i]['measurement_value'] = None
self.logger.debug("[LCD {}] No data returned "
"from influxdb".format(self.lcd_id))
except Exception as except_msg:
self.logger.debug("[LCD {}] Failed to read "
"measurement from the influxdb database: "
"{}".format(self.lcd_id, except_msg))
try:
if last_measurement_success:
# Determine if the LCD output will have a value unit
measurement = ''
if self.lcd_line[i]['measurement'] == 'setpoint':
with session_scope(MYCODO_DB_PATH) as new_session:
pid = new_session.query(PID).filter(
PID.id == self.lcd_line[i]['id']).first()
new_session.expunge_all()
new_session.close()
measurement = pid.measure_type
elif self.lcd_line[i]['measurement'] in ['temperature',
'temperature_die',
'temperature_object',
'humidity',
'co2',
'lux',
'pressure',
'altitude']:
measurement = self.lcd_line[i]['measurement']
elif self.lcd_line[i]['measurement'] == 'duration_sec':
measurement = 'duration_sec'
# Produce the line that will be displayed on the LCD
number_characters = self.lcd_x_characters
if self.lcd_line[i]['measurement'] == 'time':
# Convert UTC timestamp to local timezone
utc_dt = datetime.datetime.strptime(self.lcd_line[i]['time'].split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
self.lcd_string_line[i] = str(datetime.datetime.fromtimestamp(utc_timestamp))
elif measurement:
value_length = len(str(self.lcd_line[i]['measurement_value']))
unit_length = len(self.measurement_unit['metric'][measurement])
name_length = number_characters - value_length - unit_length - 2
name_cropped = self.lcd_line[i]['name'].ljust(name_length)[:name_length]
self.lcd_string_line[i] = '{} {} {}'.format(
name_cropped,
self.lcd_line[i]['measurement_value'],
self.measurement_unit['metric'][measurement])
else:
value_length = len(str(self.lcd_line[i]['measurement_value']))
name_length = number_characters - value_length - 1
name_cropped = self.lcd_line[i]['name'][:name_length]
self.lcd_string_line[i] = '{} {}'.format(
name_cropped,
self.lcd_line[i]['measurement_value'])
else:
self.lcd_string_line[i] = 'NO DATA < 5 MIN'
except Exception as except_msg:
self.logger.exception("[LCD {}] Error ({}): {}".format(
self.lcd_id, except_msg))
else:
self.lcd_string_line[i] = ''