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OPC UA Server ACAP

This repository contains the source code to build a small example ACAP version 4 (native) application that uses D-Bus to get

• temperature sensor data from com.axis.TemperatureController
• IO port states from com.axis.IOControl.State

and expose them as OPC UA with an open62541 server. It serves as an example of how easy it actually is to integrate any Axis device in an OPC UA system.

Note

Even if this application would fit right into your usecase, its purpose is above all to serve as an example and boilerplate rather than being ready for production.

Build

The build step creates eap (embedded application package) packages that can then be deployed on the target Axis device e.g. via the device's web UI.

For more information about the eap files, their content, and other ways to deploy, please see the documentation on how to Develop ACAP applications.

The build uses Docker and the containerized ACAP SDK. If you have make on your computer the Docker commands are nicely wrapped in the Makefile. All you need to do then is:

make dockerbuild

or perhaps build in parallel:

make -j dockerbuild

If you do have Docker but no make on your system:

# 32-bit ARM, e.g. ARTPEC-6- and ARTPEC-7-based devices
DOCKER_BUILDKIT=1 docker build --build-arg ARCH=armv7hf -o type=local,dest=. .
# 64-bit ARM, e.g. ARTPEC-8-based devices
DOCKER_BUILDKIT=1 docker build --build-arg ARCH=aarch64 -o type=local,dest=. .

Setup

Manual installation and configuration

Upload the ACAP application file (the file with the .eap extension for the camera's architecture) through the camera's web UI: Apps->Add app

The OPC UA Server port (default is 4840) can be set through the application's parameter settings, found in the three vertical dots menu:

Scripted installation and configuration

Use the camera's applications/upload.cgi to upload the ACAP application file (the file with the .eap extension for the camera's architecture):

curl -k --anyauth -u root:<password> \
    -F packfil=@OPC_UA_Server_<version>_<architecture>.eap \
    https://<camera hostname/ip>/axis-cgi/applications/upload.cgi

To start (or stop/restart/remove) the application, you can make a call like this:

curl -k --anyauth -u root:<password> \
    'https://<camera hostname/ip>/axis-cgi/applications/control.cgi?package=opcuaserver&action=start'

Use the camera's param.cgi to get or set the OPC UA server port number.

The call

curl -k --anyauth -u root:<password> \
    'https://<camera hostname/ip>/axis-cgi/param.cgi?action=list&group=opcuaserver'

will list the current setting:

root.Opcuaserver.port=4840

If you want to set the OPC UA server port to e.g. 4842:

curl -k --anyauth -u root:<password> \
    'https://<camera hostname/ip>/axis-cgi/param.cgi?action=update&opcuaserver.port=4842'

Usage

Attach an OPC UA client to the port set in the ACAP application. The client will then be able to read the values (and their timestamps) from the ACAP application's OPC UA server.

Note

The application will also log the values in the camera's syslog.

License

Apache 2.0