mbus-network 0.6.0

Provides network transport layer functionalities for modbus-rs project
Documentation

mbus-network

mbus-network is a helper crate for modbus-rs.

It provides a standard Modbus TCP transport implementation that plugs into the shared transport abstractions from mbus-core.

If you want a single top-level API, use modbus-rs. If you need direct transport-level control, use mbus-network directly.

Helper Crate Role

mbus-network is transport-focused and intentionally small:

  • Implements Transport from mbus-core using std::net::TcpStream.
  • Handles connection setup, send, receive, and disconnect for Modbus TCP.
  • Maps I/O failures into TransportError.

This crate does not implement request orchestration or function-code services. That logic is provided by mbus-client.

What Is Included

  • StdTcpTransport: concrete transport implementation for Modbus TCP.
  • Timeout setup from ModbusTcpConfig.
  • Basic DNS resolution and connect flow.
  • Non-blocking receive pass that returns currently available bytes.

Public API Surface

The crate currently re-exports:

  • StdTcpTransport

from:

  • management::std_transport

Usage

1) Add dependencies

[dependencies]
modbus-rs = "0.6.0"

2) Create TCP config and connect transport

use modbus_rs::{MbusError, ModbusConfig, ModbusTcpConfig, StdTcpTransport, Transport};

fn connect_tcp() -> Result<(), MbusError> {
		let config = ModbusConfig::Tcp(ModbusTcpConfig::new("127.0.0.1", 502)?);

		let mut transport = StdTcpTransport::new();
		transport.connect(&config)?;

		// send/recv calls are typically driven by higher-level client logic

		transport.disconnect()?;
		Ok(())
}

Configuration Notes

  • Use ModbusConfig::Tcp(...) when calling connect. Passing a serial config returns a transport configuration error.
  • connection_timeout_ms and response_timeout_ms from ModbusTcpConfig are applied to the underlying stream.

Logging

mbus-network supports optional logging via the log facade.

  • Enable feature: logging
  • This only emits through the facade; your application provides a logger backend.

Example dependency setup:

[dependencies]
mbus-network = { version = "0.6.0", features = ["logging"] }
env_logger = "0.11"

Receive Behavior

  • recv() returns bytes currently available from the socket.
  • A full Modbus ADU may arrive in multiple chunks.
  • Higher-level logic should buffer and frame messages as needed.

Typical Integration Pattern

In most applications, mbus-network is used together with mbus-client:

  1. Build ModbusConfig::Tcp(...).
  2. Instantiate StdTcpTransport.
  3. Pass transport into ClientServices from mbus-client.
  4. Use client services to issue function-code operations.

License

Copyright (C) 2025 Raghava Challari

This project is currently licensed under GNU GPL v3.0. See LICENSE for details.

This crate is licensed under GPLv3. If you require a commercial license to use this crate in a proprietary project, please contact ch.raghava44@gmail.com to purchase a license.

Contact

For questions or support: