Refactored SensorBackend and derived classes and added BME280 sensor

plugin and backend
This commit is contained in:
Fabio Manganiello 2019-08-14 19:49:19 +02:00
parent d4800b5c55
commit 757e0ff9bf
8 changed files with 195 additions and 53 deletions

View file

@ -1,6 +1,7 @@
import time
from platypush.backend import Backend
from platypush.context import get_plugin
from platypush.message.event.sensor import SensorDataChangeEvent, \
SensorDataAboveThresholdEvent, SensorDataBelowThresholdEvent
@ -18,62 +19,145 @@ class SensorBackend(Backend):
gone below a configured threshold
"""
def __init__(self, thresholds=None, poll_seconds=None, **kwargs):
default_tolerance = 1e-7
def __init__(self, plugin=None, plugin_args=None, thresholds=None, tolerance=default_tolerance, poll_seconds=None,
enabled_sensors=None, **kwargs):
"""
:param plugin: If set, then this plugin instance, referenced by plugin id, will be polled
through ``get_plugin()``. Example: ``'gpio.sensor.bme280'`` or ``'gpio.sensor.envirophat'``.
:type plugin: str
:param plugin_args: If plugin is set and its ``get_measurement()`` method accepts optional arguments, then you
can pass those arguments through ``plugin_args``.
:type plugin_args: dict
:param thresholds: Thresholds can be either a scalar value or a dictionary (e.g. ``{"temperature": 20.0}``).
Sensor threshold events will be fired when measurements get above or below these values.
Set it as a scalar if your get_measurement() code returns a scalar, as a dictionary if it returns a
dictionary of values.
dictionary of values. For instance, if your sensor code returns both humidity and temperature in a format
like ``{'humidity':60.0, 'temperature': 25.0}``, you'll want to set up a threshold on temperature with a
syntax like ``{'temperature':20.0}`` to trigger events when the temperature goes above/below 20 degrees.
For instance, if your sensor code returns both humidity and
temperature in a format like ``{'humidity':60.0, 'temperature': 25.0}``,
you'll want to set up a threshold on temperature with a syntax like
``{'temperature':20.0}`` to trigger events when the temperature goes
above/below 20 degrees.
:param tolerance: If set, then the sensor change events will be triggered only if the difference between
the new value and the previous value is higher than the specified tolerance. Example::
{
"temperature": 0.01, # Tolerance on the 2nd decimal digit
"humidity": 0.1 # Tolerance on the 1st decimal digit
}
:type tolerance: dict or float
:param poll_seconds: If set, the thread will wait for the specified number of seconds between a read and the
next one.
:type poll_seconds: float
:param enabled_sensors: If ``get_measurement()`` returns data in dict form, then ``enabled_sensors`` selects
which keys should be taken into account when monitoring for new events (e.g. "temperature" or "humidity").
:type enabled_sensors: dict (in the form ``name -> [True/False]``), set or list
"""
super().__init__(**kwargs)
self.data = None
self.plugin = plugin
self.plugin_args = plugin_args or {}
self.thresholds = thresholds
self.tolerance = tolerance or {}
self.poll_seconds = poll_seconds
if isinstance(enabled_sensors, list):
enabled_sensors = set(enabled_sensors)
if isinstance(enabled_sensors, set):
enabled_sensors = {k: True for k in enabled_sensors}
self.enabled_sensors = enabled_sensors or {}
def get_measurement(self):
""" To be implemented by derived classes """
raise NotImplementedError('To be implemented in a derived class')
"""
Wrapper around ``plugin.get_measurement()`` that can filter events on specified enabled sensors data or on
specified tolerance values. It can be overridden by derived classes.
"""
if not self.plugin:
raise NotImplementedError('No plugin specified')
plugin = get_plugin(self.plugin)
data = plugin.get_data(**self.plugin_args).output
if self.enabled_sensors:
data = {
sensor: data[sensor]
for sensor, enabled in self.enabled_sensors.items()
if enabled and sensor in data
}
return data
def get_new_data(self, new_data):
if self.data is None or new_data is None:
return new_data
# noinspection PyBroadException
try:
# Scalar data case
new_data = float(new_data)
return new_data if abs(new_data - self.data) >= self.tolerance else None
except:
# If it's not a scalar then it should be a dict
assert isinstance(new_data, dict)
ret = {}
for k, v in new_data.items():
if (v is None and self.data.get(k) is not None) \
or k not in self.data \
or self.tolerance is None:
ret[k] = v
continue
if isinstance(self.tolerance, dict):
tolerance = self.tolerance.get(k, self.default_tolerance)
else:
try:
tolerance = float(self.tolerance)
except (TypeError, ValueError):
continue
if abs(v - self.data.get(k)) >= tolerance:
ret[k] = v
return ret
def run(self):
super().run()
self.logger.info('Initialized {} sensor backend'.format(self.__class__.__name__))
while not self.should_stop():
new_data = self.get_measurement()
if self.data is None or self.data != new_data:
data = self.get_measurement()
new_data = self.get_new_data(data)
if new_data:
self.bus.post(SensorDataChangeEvent(data=new_data))
data_below_threshold = {}
data_above_threshold = {}
if self.thresholds:
if isinstance(self.thresholds, dict) and isinstance(new_data, dict):
if isinstance(self.thresholds, dict) and isinstance(data, dict):
for (measure, thresholds) in self.thresholds.items():
if measure not in new_data:
if measure not in data:
continue
if not isinstance(thresholds, list):
thresholds = [thresholds]
for threshold in thresholds:
if new_data[measure] > threshold and (self.data is None or (
if data[measure] > threshold and (self.data is None or (
measure in self.data and self.data[measure] <= threshold)):
data_above_threshold[measure] = new_data[measure]
elif new_data[measure] < threshold and (self.data is None or (
data_above_threshold[measure] = data[measure]
elif data[measure] < threshold and (self.data is None or (
measure in self.data and self.data[measure] >= threshold)):
data_below_threshold[measure] = new_data[measure]
data_below_threshold[measure] = data[measure]
if data_below_threshold:
self.bus.post(SensorDataBelowThresholdEvent(data=data_below_threshold))

View file

@ -1,5 +1,4 @@
from platypush.backend.sensor import SensorBackend
from platypush.context import get_plugin
class SensorAccelerometerBackend(SensorBackend):
@ -12,11 +11,8 @@ class SensorAccelerometerBackend(SensorBackend):
* The :mod:`platypush.plugins.gpio.sensor.accelerometer` plugin configured
"""
def get_measurement(self):
""" get_measurement implementation """
plugin = get_plugin('gpio.sensor.accelerometer')
return plugin.get_data().output
def __init__(self, **kwargs):
super().__init__(plugin='gpio.sensor.accelerometer', **kwargs)
# vim:sw=4:ts=4:et:

View file

@ -0,0 +1,30 @@
from platypush.backend.sensor import SensorBackend
class SensorBme280Backend(SensorBackend):
"""
Backend to poll analog sensor values from a `BME280 <https://shop.pimoroni.com/products/bme280-breakout>`_
environment sensor
Requires:
* ``pimoroni-bme280`` (``pip install pimoroni-bme280``)
"""
def __init__(self, temperature=True, pressure=True, humidity=True, **kwargs):
"""
:param temperature: Enable temperature sensor polling
:param pressure: Enable pressure sensor polling
:param humidity: Enable humidity sensor polling
"""
enabled_sensors = {
'temperature': temperature,
'pressure': pressure,
'humidity': humidity,
}
super().__init__(plugin='gpio.sensor.bme280', enabled_sensors=enabled_sensors, **kwargs)
# vim:sw=4:ts=4:et:

View file

@ -1,11 +1,10 @@
from platypush.backend.sensor import SensorBackend
from platypush.context import get_plugin
class SensorEnvirophatBackend(SensorBackend):
"""
Backend to poll analog sensor values from an MCP3008 chipset
(https://learn.adafruit.com/raspberry-pi-analog-to-digital-converters/mcp3008)
Backend to poll analog sensor values from an enviroPHAT sensor pHAT
(https://shop.pimoroni.com/products/enviro-phat)
Requires:
@ -24,11 +23,8 @@ class SensorEnvirophatBackend(SensorBackend):
:param magnetometer: Enable magnetometer polling
:param qnh: Base reference for your sea level pressure (for altitude sensor)
"""
super().__init__(self, **kwargs)
self.qnh = qnh
self._last_read = {}
self.enabled_sensors = {
enabled_sensors = {
'temperature': temperature,
'pressure': pressure,
'altitude': altitude,
@ -38,17 +34,9 @@ class SensorEnvirophatBackend(SensorBackend):
'magnetometer': magnetometer,
}
def get_measurement(self):
plugin = get_plugin('gpio.sensor.envirophat')
sensors = plugin.get_data(qnh=self.qnh).output
ret = {
sensor: sensors[sensor]
for sensor, enabled in self.enabled_sensors.items()
if enabled and sensor in sensors and sensors[sensor] != self._last_read.get(sensor)
}
self._last_read = sensors
return ret
super().__init__(plugin='gpio.sensor.envirophat',
plugin_args={'qnh': qnh},
enabled_sensors=enabled_sensors, **kwargs)
# vim:sw=4:ts=4:et:

View file

@ -1,5 +1,4 @@
from platypush.backend.sensor import SensorBackend
from platypush.context import get_plugin
class SensorMcp3008Backend(SensorBackend):
@ -13,10 +12,8 @@ class SensorMcp3008Backend(SensorBackend):
* The :mod:`platypush.plugins.gpio.sensor.mcp3008` plugin configured
"""
def get_measurement(self):
""" get_measurement implementation """
plugin = get_plugin('gpio.sensor.mcp3008')
return plugin.get_data().output
def __init__(self, **kwargs):
super().__init__(plugin='gpio.sensor.mcp3008', **kwargs)
# vim:sw=4:ts=4:et:

View file

@ -1,5 +1,4 @@
from platypush.backend.sensor import SensorBackend
from platypush.context import get_plugin
class SensorSerialBackend(SensorBackend):
@ -12,10 +11,8 @@ class SensorSerialBackend(SensorBackend):
* The :mod:`platypush.plugins.serial` plugin configured
"""
def get_measurement(self):
""" Implementation of ``get_measurement`` """
plugin = get_plugin('serial')
return plugin.get_data().output
def __init__(self, **kwargs):
super().__init__(plugin='gpio.sensor.serial', **kwargs)
# vim:sw=4:ts=4:et:

View file

@ -7,8 +7,8 @@ class GpioSensorPlugin(Plugin):
should implement this class (and the get_measurement() method)
"""
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
def __init__(self, **kwargs):
super().__init__(**kwargs)
@action
def get_measurement(self, *args, **kwargs):

View file

@ -0,0 +1,50 @@
from platypush.plugins import action
from platypush.plugins.gpio.sensor import GpioSensorPlugin
class GpioSensorBme280Plugin(GpioSensorPlugin):
"""
Plugin to interact with a `BME280 <https://shop.pimoroni.com/products/bme280-breakout>`_ environment sensor for
temperature, humidity and pressure measurements over I2C interface
Requires:
* ``pimoroni-bme280`` (``pip install pimoroni-bme280``)
"""
def __init__(self, port=1, **kwargs):
"""
:param port: I2C port. 0 = /dev/i2c-0 (port I2C0), 1 = /dev/i2c-1 (port I2C1)
"""
super().__init__(**kwargs)
self.port = port
# noinspection PyPackageRequirements
# noinspection PyUnresolvedReferences
@action
def get_measurement(self):
"""
:returns: dict. Example::
output = {
"temperature": 21.0, # Celsius
"pressure": 101555.08, # Pascals
"humidity": 23.543, # percentage
}
"""
from smbus import SMBus
from bme280 import BME280
bus = SMBus(self.port)
device = BME280(i2c_dev=bus)
return {
'temperature': device.get_temperature(),
'pressure': device.get_pressure()*100,
'humidity': device.get_humidity(),
}
# vim:sw=4:ts=4:et: