167 lines
5.9 KiB
Python

import queue
import datetime
import threading
class AbstractModbusDatapoint(object):
def __init__(self, label, unit, address, count, scanRate):
self.label = label
self.unit = unit
self.address = address
self.count = count
self.scanRate = scanRate
self.type = 'abstract data point'
self.enqueued = False
if self.scanRate:
self.priority = 1
else:
self.priority = 0
def __lt__(self, other): return self.priority < other.priority
def __le__(self, other): return self.priority <= other.priority
def __eq__(self, other): return self.priority == other.priority
def __ne__(self, other): return self.priority != other.priority
def __gt__(self, other): return self.priority > other.priority
def __ge__(self, other): return self.priority >= other.priority
def __str__(self):
return "{0}, {1}: {2} {3} {4}".format(self.type, self.label, self.unit, self.address, self.count)
class HoldingRegisterDatapoint(AbstractModbusDatapoint):
def __init__(self, label, unit, address, count, scanRate, publishTopic, subscribeTopic, feedbackTopic):
super(HoldingRegisterDatapoint, self).__init__(label, unit, address, count, scanRate)
self.publishTopic = publishTopic
self.subscribeTopic = subscribeTopic
self.feedbackTopic = feedbackTopic
self.writeRequestValue = None
self.lastContact = None
self.type = 'read holding register'
def process(self):
successFull = False
giveUp = False
if self.writeRequestValue:
# perform write operation
if successFull:
# give feedback
self.writeRequestValue = None
else:
# retries handling
if giveUp:
# give negative feedback
self.writeRequestValue = None
else:
# perform read operation
if successFull:
self.lastContact = datetime.datetime.now()
# publish value
else:
# retries handling
if giveUp:
# backoff and availability handling
# give negative feedback
pass
def onMessage(self, value):
self.writeRequestValue = value
class MqttProcessor(threading.Thread):
def __init__(self, registers, queue):
super(MqttProcessor, self).__init__()
self.registers = registers
self.queue = queue
def run(self):
pass
# set mqtt callbacks
# mqtt connect
# mqtt loop forever
def onConnect(self):
pass
# subscribe to all subscribe topics from registers
def onMessage(self, topic, payload):
pass
# call onMessage method of register with related subscribe topic
# put register yourself in high prio queue
# self.put(r)
class ScanRateConsideringQueueFeeder(threading.Thread):
def __init__(self, registers, queue):
super(ScanRateConsideringQueueFeeder, self).__init__()
self.registers = registers
self.queue = queue
def run(self):
while True:
registersToBeHandled = [
r for r in self.registers if ((not r.enqueued) and
(r.scanRate) and
((not r.lastContact) or
(r.lastContact + r.scanRate < datetime.datetime.now())))
]
registersToBeHandled.sort(key=lambda x : x.scanRate)
for r in registersToBeHandled:
self.queue.put(r)
r.enqueued = True
class CommunicationProcessor(threading.Thread):
def __init__(self, queue):
super(CommunicationProcessor, self).__init__()
self.queue = queue
def run(self):
while True:
r = self.queue.get()
# r.process()
r.lastContact = datetime.datetime.now()
print("Dequeued: {0!s}".format(r))
r.enqueued = False
# ModbusRequestDefinition(4, 0x2000, 2, 'F', '(ERR) Unavailable device'),
# ModbusRequestDefinition(1, 0x2000, 4, 'F', '(ERR) Wrong register size'),
# ModbusRequestDefinition(1, 0x2000, 2, 'F', 'Voltage'),
# ModbusRequestDefinition(1, 0x2020, 2, 'F', 'Frequency'),
# ModbusRequestDefinition(1, 0x2060, 2, 'F', 'Current'),
# ModbusRequestDefinition(3, 0x0004, 2, 'RF', 'Resistance Channel 1'),
# ModbusRequestDefinition(3, 0x000C, 2, 'RF', 'Temperature Channel 1'),
# ModbusRequestDefinition(3, 0x0014, 2, 'RF', 'Resistance Channel 2'),
# ModbusRequestDefinition(3, 0x001C, 2, 'RF', 'Temperature Channel 2'),
datapoints = [
HoldingRegisterDatapoint('Voltage', 1, 0x2000, 2, datetime.timedelta(seconds=10), 'Pub/Voltage', None, None),
HoldingRegisterDatapoint('Frequency', 1, 0x2020, 2, datetime.timedelta(seconds=10), 'Pub/Frequency', None, None),
HoldingRegisterDatapoint('Current', 1, 0x2060, 2, datetime.timedelta(seconds=10), 'Pub/Current', None, None),
HoldingRegisterDatapoint('Resistance Channel 1', 2, 0x0004, 2, datetime.timedelta(seconds=1), 'Pub/ResistanceChannel1', None, None),
HoldingRegisterDatapoint('Temperature Channel 1', 2, 0x000c, 2, datetime.timedelta(seconds=1), 'Pub/TemperatureChannel1', None, None),
HoldingRegisterDatapoint('Resistance Channel 2', 2, 0x0014, 2, datetime.timedelta(seconds=1), 'Pub/ResistanceChannel2', None, None),
HoldingRegisterDatapoint('Temperature Channel 2', 2, 0x001c, 2, datetime.timedelta(seconds=1), 'Pub/TemperatureChannel2', None, None),
HoldingRegisterDatapoint('Relay1', 5, 0x0001, 1, None, None, 'Sub/Relay1', 'Feedback/Relay1')
]
queue = queue.PriorityQueue()
if __name__ == "__main__":
cp = CommunicationProcessor(queue)
cp.start()
qf = ScanRateConsideringQueueFeeder(datapoints, queue)
qf.start()