Introduction

This is an OPC UA server / client API implementation for Rust.

OPC-UA is an industry standard for information modeling and communication. It is used for control systems, IoT, etc.

The OPC-UA standard is very large and complex, and implementations are often flawed. The strictness of Rust makes it a good choice for implementing OPC-UA, and the performance characteristics are useful when creating OPC-UA tooling that will run in constrained environments.

Read the compatibility page for how the implementation conforms with the OPC UA spec.

Read the change log for changes per version as well as aspirational / upcoming work.

This is a fork

This is a fork of opcua with a broader goal of a generic OPC-UA implementation and a number of different design decisions. See fork.md for details on this decision and the differences between this library and the original.

MSRV Policy

We target the latest stable rust compiler and make no promises of support for older rust versions. We have use for several recent and upcoming rust features so this is unlikely to change.

License

The code is licenced under MPL-2.0. Like all open source code, you use this code at your own risk.

Setup

Read the setup for instructions on building OPCUA for Rust.

Read cross compilation for hints for cross compiling OPC UA for Rust to other platforms.

Migration notes

If you're using an earlier version of OPC UA for Rust, read the migration notes.

Design

Read the design for more in-depth description of implementation.

Tutorial

Tutorials / user guides are still work in progress.

• Client Tutorial
• Server Tutorial

Further Documentation

The API documentation is generated from the latest published crates. This may be some way behind current development.

Samples

If you want to get stuck in, there are a number of samples in the samples/ folder. The simple-client and the simple-server projects are minimal client and server programs respectively.

# In one bash
cd opcua/samples/simple-server
cargo run
# In another bash
cd opcua/samples/simple-client
cargo run

The full list of samples:

1. simple-server - an OPC UA server that adds 4 variables v1, v2, v3 and v4 and updates them from a timer via push and pull mechanisms.
2. simple-client - an OPC UA client that connects to a server and subscribes to the values of v1, v2, v3 and v4.
3. discovery-client - an OPC UA client that connects to a discovery server and lists the servers registered on it.
4. chess-server - an OPC UA server that connects to a chess engine as its back end and updates variables representing the state of the game.
5. demo-server - an OPC UA server that is more complex than the simple server and can be used for compliance testing.
6. mqtt-client - an OPC UA client that subscribes to some values and publishes them to an MQTT broker.
7. event-client - an OPC UA client that will connect to a server and subscribe to alarms / events.