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Opex62541 is an Elixir wrapper for the open62541 library; open62541 is an open-source implementation of OPC UA (OPC Unified Architecture) aka IEC 62541 licensed under Mozilla Public License v2.0.

Content

• Features
• Installation
  • Compatibility
  • Nerves
  • Customized build
• Documentation
• Contributing
• License
• TODO

Features

This library implements the following features from open62541:

• Communication Stack
  • OPC UA binary protocol
  • Secure communication with encrypted messages
• Server
  • Support for all OPC UA node types
  • Access control for individual nodes
  • Support for adding and removing nodes and references also at runtime.
  • Support for inheritance and instantiation of object and variable-types.
  • Support for subscriptions/monitored items.
• Client
  • All OPC UA services supported
  • Support for subscriptions/monitored items.

Installation

To install this package, add opex62541 to your list of dependencies in mix.exs:

def deps do
  [
    {:opex62541, git: "https://github.com/valiot/opex62541"}
  ]
end

Breaking Changes (v1.4.x Migration)

Important: This library now uses open62541 v1.4.12 with OpenSSL as the encryption backend instead of mbedTLS.

System Dependencies Required:

• Ubuntu/Debian:

  sudo apt-get install git build-essential gcc pkg-config cmake python libssl-dev

• Arch Linux:

  sudo pacman -S git base-devel gcc pkg-config cmake python openssl

• Nerves: OpenSSL is already included in the Nerves system. No additional configuration needed.

Backward Compatibility:

If you need to use the legacy v1.0 with mbedTLS for existing projects, set the environment variable:

export OPEN62541_DOWNLOAD_VERSION=v1.0

Note: v1.0 requires mbedTLS instead of OpenSSL. Install with:

sudo apt-get install libmbedtls-dev  # Ubuntu/Debian

Compatibility

Opex62541 is now based on open62541 v1.4.14 with Elixir 1.10.0+. It was tested on:

• Ubuntu 18.04, 20.04, 22.04
• Raspbian OS (Raspberry Pi 3B+)
• Nerves (Raspberry Pi 3B+)

Nerves

Nerves is a complete IoT platform and infrastructure to build and deploy maintainable embedded systems to boards such as Raspberry Pi or Beaglebone.

Good news: OpenSSL is already included in standard Nerves systems. No additional configuration or custom system is required for opex62541 to work with encryption enabled.

Customized builds

By default, Opex62541 downloads and compiles the v1.4.14 release of open62541 with OpenSSL encryption. If you want to compile it manually or change the default version, use the following example commands to set the desired env variables:

export MANUAL_BUILD=true

export OPEN62541_DOWNLOAD_VERSION=v1.4.14

The open62541 project uses CMake to manage the build options for code generation and to generate build projects for the different systems and IDEs. To overwrite the default options, use OPEN62541_BUILD_ARGS as follows:

export OPEN62541_BUILD_ARGS='-DCMAKE_BUILD_TYPE=Release -DUA_NAMESPACE_ZERO=MINIMAL'

Default values for OPEN62541_BUILD_ARGS are -DBUILD_SHARED_LIBS=ON -DCMAKE_BUILD_TYPE=RelWithDebInfo -DUA_NAMESPACE_ZERO=FULL -DUA_LOGLEVEL=601 -DUA_ENABLE_DISCOVERY_MULTICAST=ON -DUA_ENABLE_AMALGAMATION=ON -DUA_ENABLE_ENCRYPTION=OPENSSL.

Docker Container

To build the container locally use:

git clone https://github.com/valiot/opex62541
cd opex62541
docker build -t <name:tag> .

You can use this container to test this application.

Documentation

For detailed documentation and tutorials refer to hexdocs.pm.

Contributing

• Fork our repository on Github.
• Fix or add what is needed.
• Commit to your repository
• Issue a Github Pull Request.
• Fill the pull request template.

If you wish to clone this repository, use:

git clone https://github.com/valiot/opex62541.git

License

See LICENSE.

TODO

• Methods
• OPC UA PubSub
• Better C code handling for the Client and Server common code