Open Source C++ OPC-UA Server and Client Library

LGPL OPC-UA server and client library written in C++ and with a lot of code auto-generated from xml specification using python.

Python bindings can be found in the python directory.

code: https://github.com/FreeOpcUa/freeopcua
website: http://freeopcua.github.io/
mailing list: https://groups.google.com/forum/#!forum/freeopcua

Currently supported:

• read, write, browse
• translateBrowsePathToNodeId
• DataChange Events
• Events
• Subscriptions
• complete opc-ua address space generated from xml specification
• Method call from client
• Linux and Windows(VS13) support

Work in progress

• StatusChange Events
• Filtering
• Documentation
• Automatic generation of binary protocol from OPC schema files
• • Methods on server side

Not implemented yet (patches are welcome)

• History
• Security: Authentication, Certificates handling, ..

Usage

Documentation is sparse but several examples are availables:

C++ examples in https://github.com/FreeOpcUa/freeopcua/tree/master/src/examples
Python examples in https://github.com/FreeOpcUa/freeopcua/tree/master/python/src
https://github.com/FreeOpcUa/freeopcua/blob/master/python/tests/test_highlevel.py can also be a usefull source of information

Example minimal client in python

  client = opcua.Client(False)
  client.connect("opc.tcp://10.10.10.4:4841/OPCUA/AnyServer/")

  objects = client.get_objects_node()
  print("Children of objects are: ", objects.get_children())

  var = objects.get_child(["3:AnObject", "AVariable"])
  print("Value of variable is: ", var.get_value())
  
  client.disconnect()

Tested clients and servers with default settings

• uaexperts client application
• node-opcua (client and server tested)
• ignition server
• Beckhoff PLC (seems to be some issues, but mostly working)
• ignition open-source sdk (server tested)
• quickopc client sdk
• prosysopc demo client
• prosysopc demo server
• unified automation sdk (client and server tested)

Installation

An environment supporting c++11 is necessary: gcc-4.8+, clang 3.4 or VS2013

Ubuntu (Debians)

There is a script debian.soft in the root for installing all required soft to build all repositories.

Using GNU autotools

autoreconf -f -i
./configure --prefix=/path/to/server
make 
make check
make install
cd /path/to/server
LD_LIBRARY_PATH=./lib ./bin/opcuaserver

Using cmake

Linux

mkdir build
cd build
cmake ..
make
make test

Windows

Boost and libxml2 are necessary

rem compiling
mkdir build
cd build
cmake .. -DBOOST_ROOT=c:\boost_1_56
cmake --build
ctest -C Debug
cd bin\Debug
example_server.exe

Docker

docker build .

Developement

C++ style

• 2 spaces not tab
• CamelCase
• Local variables start with small letter
• Global/member variables starts with capital letters
• Use provided automatic formatter (Artistic Style) by invoking ./restyle

python code and API should follows PEP8 (many places should be fixed)

Address space and most protocol code are auto-generated and should not be modified directly. Every auto-generated file starts with a mention that it should not be edited. There's a lot of old hand written protocol code left that should use the auto-generated code. This is done by uncommenting struct names in schemas/generate_protocol.py and removing old code and files in src/protocol and include/opc/ua/protocol/