Repl enhancements 2

[dhoomakethu]

• Fix --random in pymodbus.server to randomize values read for discrete inputs and input registers

Example invocation

pymodbus.server --verbose run  --modbus-server tcp --modbus-framer socket --modbus-port 5020 --unit-id 1 --unit-id 2 -u 4 -r 1 --timeout 2

The values for simulation can also be passed as a json file to --modbus-config param , for e.g to limit the max and min values a register should have. Refer data_block_settings in the below json file.

{
  "tcp": {
        "handler": "ModbusConnectedRequestHandler",
        "allow_reuse_address": true,
        "allow_reuse_port": true,
        "backlog": 20,
        "ignore_missing_slaves": false
    },
    "serial": {
        "handler": "ModbusSingleRequestHandler",
        "stopbits": 1,
        "bytesize": 8,
        "parity": "N",
        "baudrate": 9600,
        "timeout": 3,
        "auto_reconnect": false,
        "reconnect_delay": 2
    },
    "tls": {
        "handler": "ModbusConnectedRequestHandler",
        "certfile": null,
        "keyfile": null,
        "allow_reuse_address": true,
        "allow_reuse_port": true,
        "backlog": 20,
        "ignore_missing_slaves": false
    },
    "udp": {
        "handler": "ModbusDisonnectedRequestHandler",
        "ignore_missing_slaves": false
    },
    "data_block_settings": {
        "min_binary_value": 0,
        "max_binary_value": 1,
        "min_register_value": 0,
        "max_register_value": 100,
        "data_block": {
            "discrete_inputs": {
                "block_start": 0,
                "block_size": 100,
                "default": 0,
                "sparse": false
            },
            "coils": {
                "block_start": 0,
                "block_size": 100,
                "default": 0,
                "sparse": false
            },
            "holding_registers": {
                "block_start": 0,
                "block_size": 100,
                "default": 0,
                "sparse": false
            },
            "input_registers": {
                "block_start": 0,
                "block_size": 100,
                "default": 0,
                "sparse": false
            }

        }


    }
}

TODO

• Update unit tests
• Update documentation

[dhoomakethu]

Updated documentation https://github.com/riptideio/pymodbus/blob/repl-enhancements-2/pymodbus/repl/server/README.md

[janiversen]

I am hoping to make 3.0.1 around November 5, does that give you enough time to merge this ?

If not I will pospone the release a bit.

[janiversen]

The CI error might be mine, will look at it Monday.

[dhoomakethu]

Ok, I will poke around a bit tomorrow to see if I can fix it.

[janiversen]

Don’t’t worry as you can see it is a temporary error, restarting the job cures the problem.

[serroba]

thanks a lot for adding this example section. Super useful

[serroba]

should this functionality work for single bit object types? I was thinking about coils.
Not sure if is really much value, but for my own tests that would be nice, although the complexity of randomise booleans is much less.

Anyhow, just wondering about your thoughts about those objects.

[dhoomakethu]

Holding registers and coils can be overridden and hence they are excluded from simulation. Bit fields should be straight forward (0 or 1)

[serroba]

Right that makes sense

[dhoomakethu]

@janiversen I may not be able to finish writing the test cases for this PR by first week of November, Please feel free to drop this from the next release if you think having tests are a must. You can merge otherwise and I will add tests in future.

[janiversen]

Thanks for the heads up. I still have a couple of days work on the new datastore (adding tests), once done I will merge this one and make the release.

As you say test can come later.

[janiversen]

I will merge this now, because I am testing/pre-building doc and sources to see what more we need, please make the tests in a new PR.