virtual-drivers/modbus.py incorrectly opens .csv file in binary mode

[awoz]

Description of Issue

When running the virtual-drivers/modbus.py script with the catalyst371.csv device registry config file, parse_config() fails and reports:

_csv.Error: iterator should return strings, not bytes (did you open the file in text mode?)

Affected Version

8.1.3

Screenshots

~/volttron$ /home/volttron/volttron/env/bin/python scripts/scalability-testing/virtual-drivers/modbus.py examples/configurations/drivers/catalyst371.csv 127.0.0.2 --no-daemon --port 502 Traceback (most recent call last): File "scripts/scalability-testing/virtual-drivers/modbus.py", line 262, in abstraction = DeviceAbstraction(args.config) File "scripts/scalability-testing/virtual-drivers/modbus.py", line 140, in init self.parse_config(config_file) File "scripts/scalability-testing/virtual-drivers/modbus.py", line 178, in parse_config for regDef in configDict: File "/usr/lib/python3.8/csv.py", line 110, in next self.fieldnames File "/usr/lib/python3.8/csv.py", line 97, in fieldnames self._fieldnames = next(self.reader) _csv.Error: iterator should return strings, not bytes (did you open the file in text mode?)

Expected

parse_config() method at virtual-drivers/modbus.py should pass when it processes the .csv registry file.

Actual

parse_config() method at virtual-drivers/modbus.py fails and reports:

_csv.Error: iterator should return strings, not bytes (did you open the file in text mode?)

Steps to Reproduce

~/volttron$ source env/bin/activate ~/volttron$ ./start-volttron ~/volttron$ /home/volttron/volttron/env/bin/python scripts/scalability-testing/virtual-drivers/modbus.py examples/configurations/drivers/catalyst371.csv 127.0.0.2 --no-daemon --port 502

Additional Details

It was verified that specified .csv file is "text" and not binary:

~/volttron$ file examples/configurations/drivers/catalyst371.csv examples/configurations/drivers/catalyst371.csv: CSV text

Changing the open(config_file, 'rb') statement at line 173 of virtual-drivers/modbus.py to use 'r' text mode resolves the parser issue.