Fix/Workaround for #612, #614 , avoid disconnects on succesful reads

Author: dhoomakethu

CHANGELOG.rst

@@ -3,6 +3,7 @@ version 2.5.1
 * Bug fix TCP Repl server.
 * Support multiple UID's with REPL server.
 * Support serial for URL (sync serial client)
+* Bug fix/enhancements, close socket connections only on empty or invalid response
 
 version 2.5.0
 ----------------------------------------------------------

pymodbus/transaction.py

@@ -217,19 +217,21 @@ def execute(self, request):
                                 "/Unable to decode response")
                             response = ModbusIOException(last_exception,
                                                          request.function_code)
+                        self.client.close()
                     if hasattr(self.client, "state"):
                         _logger.debug("Changing transaction state from "
                                       "'PROCESSING REPLY' to "
                                       "'TRANSACTION_COMPLETE'")
                         self.client.state = (
                             ModbusTransactionState.TRANSACTION_COMPLETE)
-                self.client.close()
+
                 return response
             except ModbusIOException as ex:
                 # Handle decode errors in processIncomingPacket method
                 _logger.exception(ex)
                 self.client.close()
                 self.client.state = ModbusTransactionState.TRANSACTION_COMPLETE
+                self.client.close()
                 return ex
 
     def _retry_transaction(self, retries, reason,

pymodbus/version.py

@@ -41,7 +41,7 @@ def __str__(self):
         return '[%s, version %s]' % (self.package, self.short())
 
 
-version = Version('pymodbus', 2, 5, 1)
+version = Version('pymodbus', 2, 5, 1, "rc1")
 
 version.__name__ = 'pymodbus'  # fix epydoc error