From e1750e53875a44eca010caed93646b4e046e1e9c Mon Sep 17 00:00:00 2001
From: Wolfgang Hottgenroth <w.hottgenroth@krohne.com>
Date: Mon, 8 Jul 2019 16:25:13 +0200
Subject: [PATCH] updateonly handling

---
 src/CmdServer.py           | 28 ++++++++++++++++++++++------
 src/RegisterDatapoint.py   | 19 +++++++++++++------
 src/initialRegisterFile.py |  6 +++---
 3 files changed, 38 insertions(+), 15 deletions(-)

diff --git a/src/CmdServer.py b/src/CmdServer.py
index 1177e06..9f4b2b1 100644
--- a/src/CmdServer.py
+++ b/src/CmdServer.py
@@ -115,30 +115,37 @@ class CmdInterpreter(cmd.Cmd):
 
     def do_add_ir(self, arg):
         try:
-            (label, unit, address, count, scanrate, readTopic) = self.splitterRe.split(arg)
+            (label, unit, address, count, scanrate, updateOnly, readTopic) = self.splitterRe.split(arg)
             self.__println("Label:         {0}".format(label))
             self.__println("Unit:          {0}".format(unit))
             self.__println("Address:       {0}".format(address))
             self.__println("Count:         {0}".format(count))
             self.__println("ScanRate:      {0}".format(scanrate))
+            self.__println("UpdateOnly:    {0}".format(updateOnly))
             self.__println("ReadTopic:     {0}".format(readTopic))
 
             if readTopic == 'None':
                 readTopic = None
+            if updateOnly in ['true', 'True', 'yes', 'Yes']:
+                updateOnly = True
+            elif updateOnly in ['false', 'False', 'no', 'No']:
+                updateOnly = False
+            else:
+                raise CmdInterpreterException('updateOnly must be true or false, yes or no')
             unit = parseIntArbitraryBase(unit)
             address = parseIntArbitraryBase(address)
             count = parseIntArbitraryBase(count)
             scanrate = float(scanrate)
             if scanrate == 0.0:
                 raise CmdInterpreterException('scanRate must not be zero')
-            r = RegisterDatapoint.InputRegisterDatapoint(label, unit, address, count, datetime.timedelta(seconds=scanrate), readTopic)
+            r = RegisterDatapoint.InputRegisterDatapoint(label, unit, address, count, datetime.timedelta(seconds=scanrate), updateOnly, readTopic)
             self.registers.append(r)
         except ValueError as e:
             self.__println("ERROR: {0!s}, {1!s}".format(e.__class__.__name__, e))
 
     def help_add_ir(self):
         self.__println("Usage: add <Label> <Unit> <Address> <Count> <ScanRate>")
-        self.__println("           <ReadTopic>")
+        self.__println("           <UpdateOnly> <ReadTopic>")
         self.__println("Adds an input register")
         self.__println("DO NOT FORGET TO SAVE AFTERWARDS!")
         self.__println("---------------------------------------------------------------------")
@@ -147,34 +154,42 @@ class CmdInterpreter(cmd.Cmd):
         self.__println("<Address>                    Register address within the device")
         self.__println("<Count>                      Count of registers to be read in words")
         self.__println("<ScanRate>                   Scanrate in seconds (float)")
+        self.__println("<UpdateOnly>                 Publish only when value has changed")
         self.__println("<ReadTopic>                  Topic to publish read data")
 
     def do_add_di(self, arg):
         try:
-            (label, unit, address, count, scanrate, readTopic) = self.splitterRe.split(arg)
+            (label, unit, address, count, scanrate, updateOnly, readTopic) = self.splitterRe.split(arg)
             self.__println("Label:         {0}".format(label))
             self.__println("Unit:          {0}".format(unit))
             self.__println("Address:       {0}".format(address))
             self.__println("Count:         {0}".format(count))
             self.__println("ScanRate:      {0}".format(scanrate))
+            self.__println("UpdateOnly:    {0}".format(updateOnly))
             self.__println("ReadTopic:     {0}".format(readTopic))
 
             if readTopic == 'None':
                 readTopic = None
+            if updateOnly in ['true', 'True', 'yes', 'Yes']:
+                updateOnly = True
+            elif updateOnly in ['false', 'False', 'no', 'No']:
+                updateOnly = False
+            else:
+                raise CmdInterpreterException('updateOnly must be true or false, yes or no')
             unit = parseIntArbitraryBase(unit)
             address = parseIntArbitraryBase(address)
             count = parseIntArbitraryBase(count)
             scanrate = float(scanrate)
             if scanrate == 0.0:
                 raise CmdInterpreterException('scanRate must not be zero')
-            r = RegisterDatapoint.DiscreteInputDatapoint(label, unit, address, count, datetime.timedelta(seconds=scanrate), readTopic)
+            r = RegisterDatapoint.DiscreteInputDatapoint(label, unit, address, count, datetime.timedelta(seconds=scanrate), updateOnly, readTopic)
             self.registers.append(r)
         except ValueError as e:
             self.__println("ERROR: {0!s}, {1!s}".format(e.__class__.__name__, e))
 
     def help_add_di(self):
         self.__println("Usage: add <Label> <Unit> <Address> <Count> <ScanRate>")
-        self.__println("           <ReadTopic>")
+        self.__println("           <UpdateOnly> <ReadTopic>")
         self.__println("Adds a discrete input")
         self.__println("DO NOT FORGET TO SAVE AFTERWARDS!")
         self.__println("---------------------------------------------------------------------")
@@ -183,6 +198,7 @@ class CmdInterpreter(cmd.Cmd):
         self.__println("<Address>                    Register address within the device")
         self.__println("<Count>                      Count of registers to be read in words")
         self.__println("<ScanRate>                   Scanrate in seconds (float)")
+        self.__println("<UpdateOnly>                 Publish only when value has changed")
         self.__println("<ReadTopic>                  Topic to publish read data")
 
     def do_list(self, arg):
diff --git a/src/RegisterDatapoint.py b/src/RegisterDatapoint.py
index 295708f..0423419 100644
--- a/src/RegisterDatapoint.py
+++ b/src/RegisterDatapoint.py
@@ -86,8 +86,10 @@ class HoldingRegisterDatapoint(AbstractModbusDatapoint):
 
 
 class InputRegisterDatapoint(AbstractModbusDatapoint):
-    def __init__(self, label, unit, address, count, scanRate, publishTopic):
+    def __init__(self, label, unit, address, count, scanRate, updateOnly, publishTopic):
         super().__init__(label, unit, address, count, scanRate)
+        self.updateOnly = updateOnly
+        self.lastValue = None
         self.publishTopic = publishTopic
         self.lastContact = None
         self.type = 'input register'
@@ -105,8 +107,10 @@ class InputRegisterDatapoint(AbstractModbusDatapoint):
                                              unit=self.unit)
         if type(result) in [ExceptionResponse, ModbusIOException]:
             raise DatapointException(result)
-        # print("{0}: {1!s}".format(self.label, result.registers))        
-        pubQueue.put(MqttProcessor.PublishItem(self.publishTopic, str(result.registers)))
+        if not self.updateOnly or (result.registers != self.lastValue):
+            self.lastValue = result.registers
+            # print("{0}: {1!s}".format(self.label, result.registers))        
+            pubQueue.put(MqttProcessor.PublishItem(self.publishTopic, str(result.registers)))
 
         if successFull:
             self.lastContact = datetime.datetime.now()
@@ -120,8 +124,10 @@ class InputRegisterDatapoint(AbstractModbusDatapoint):
 
 
 class DiscreteInputDatapoint(AbstractModbusDatapoint):
-    def __init__(self, label, unit, address, count, scanRate, publishTopic):
+    def __init__(self, label, unit, address, count, scanRate, updateOnly, publishTopic):
         super().__init__(label, unit, address, count, scanRate)
+        self.updateOnly = updateOnly
+        self.lastValue = None
         self.publishTopic = publishTopic
         self.lastContact = None
         self.type = 'discrete input'
@@ -139,8 +145,9 @@ class DiscreteInputDatapoint(AbstractModbusDatapoint):
                                              unit=self.unit)
         if type(result) in [ExceptionResponse, ModbusIOException]:
             raise DatapointException(result)
-        # print("{0}: {1!s}".format(self.label, result.bits))        
-        pubQueue.put(MqttProcessor.PublishItem(self.publishTopic, str(result.bits)))
+        if not self.updateOnly or (result.registers != self.lastValue):
+            # print("{0}: {1!s}".format(self.label, result.bits))        
+            pubQueue.put(MqttProcessor.PublishItem(self.publishTopic, str(result.bits)))
 
         if successFull:
             self.lastContact = datetime.datetime.now()
diff --git a/src/initialRegisterFile.py b/src/initialRegisterFile.py
index 95631e8..df236ea 100644
--- a/src/initialRegisterFile.py
+++ b/src/initialRegisterFile.py
@@ -4,9 +4,9 @@ import pickle
 
 
 datapoints = [
-    RegisterDatapoint.InputRegisterDatapoint('Temperature', 5, 0x0001, 1, datetime.timedelta(seconds=1.0), 'Pub/Temperature'),
-    RegisterDatapoint.InputRegisterDatapoint('Humidity', 5, 0x0002, 1, datetime.timedelta(seconds=1.0), 'Pub/Humidity'),
-    RegisterDatapoint.DiscreteInputDatapoint('Switches', 4, 0x0000, 1, datetime.timedelta(seconds=1.0), 'Pub/Switches'),
+    RegisterDatapoint.InputRegisterDatapoint('Temperature', 5, 0x0001, 1, datetime.timedelta(seconds=1.0), True, 'Pub/Temperature'),
+    RegisterDatapoint.InputRegisterDatapoint('Humidity', 5, 0x0002, 1, datetime.timedelta(seconds=1.0), True, 'Pub/Humidity'),
+    RegisterDatapoint.DiscreteInputDatapoint('Switches', 4, 0x0000, 1, datetime.timedelta(seconds=1.0), True, 'Pub/Switches'),
 ]