Can anyone help me out to implement the OPC UA client implementation using the OPC Foundation ANSI C Stack. I believe that only the server implementation is available in the repository, so far.
I have the OPC UA server working using the OPC Foundation ANSI C stack and i'm using the GUI client to communicate to the server.
It would be great if anyone helps me out to implement a simple client using the OPC Foundation ANSI C stack to connect to the server and do a data access (single variable) from the server's address space.
Why do you want to complicate your life using the stack directly? use a SDK.
Here is an open source option that offers client and server options https://open62541.org/. It comes with examples and good documentation.
Related
I am starting with websockets.
I've come across a bit of a puzzle in my head and I hope someone will be able to answer this question for me
Can I use the socket.io library on the client side and a completely different websocket library on the server side?
I am trying to work with client.py , server.cpp and a make file. I am not understanding how to run the files and work on grpc with these files. Is it possible for anyone to help me understand this concept and work with the client, server and protobuf?
The whole idea of gRPC is to enable protocol based communication between cross platform services. Means your CPP server can communicate with python client. Ref: Official gRPC Documentation
First step is to write a .proto file which is an agreement between server and client on what attributes should a request / response for a particular RPC method should contain.
Now one can implement server, client in any language of their choice. As long as server & client agree on single proto file, underlying process is abstracted by gRPC framework and it just works!!!
For fastest hands-on, Refer to quick start guides of gRPC for c++, python to implement cross platform server, client.
I have a tests for mqtt in jmeter. i want to use jmeter for sending opc ua requests using jmeter.
is it possible to use Jmeter for testing OPC ua?
can we send opc client requests via jmeter?
Out of the box JMeter doesn't support OPC UA protocol, also there are no JMeter Plugins offering such functionality (at least I'm not aware of any) so you will either have to find a client library like Java Based OPC UA Client SDK or OPC UA Java Stack and program the requests you need to send using JSR223 Samplers and Groovy language (valid Java code in the majority of cases will be valid Groovy code, or if you prefer "pure" Java you can consider developing your own JMeter Plugin) or do some reverse engineering of OPC UA protocol if above SDKs are not fulfilling your requirements.
I am still thinking what is the most proper WebSockets framework to learn, which gives me all what I want.
I am C#.Net Core programmer (it is the language I want to use to write my server with). I wanted to start learning SignalR, but I didn't start yet because I am still confused about the ability of using my SignalR server from a Microcontroller client.
Is it some how possible to use transfer data between SignalR C#.Net Core server and an ARM Cortex M4 microcontroller programmed in C (without any operating system on it)?
In case that is not possible with SignalR, which WebSockets framework may be useful for my case (C# Server <-> C client)?
Any further ideas and suggesions about that? I am still very new to WebSockets and I don't understand exactly if it is possible to use SignalR (or any WebSockets framework) server from a client uses another framework (or maybe pure websockets).
If you are using SignalR for ASP.NET Core you can actually use bare websocket to connect to the server. I showed a demo where I have 3 different clients connecting to the SignalR server. The interesting part is that one of the clients was a NodeMCU based board running lua. You can find all the details in my post including code and instructions on setting things up.
Is that possible to force the ServerXMLHTTP to connect to internet through an existing windows socket?
For some reasons, I'm using VB6 winsock control and the winsock connected to a certain PC. I want to communicate with that PC in SSL protocol, but I need to implement too much thing to make winsock work properly like ServerXMLHTTP.
So, yes or no, can I force the ServerXMLHTTP (or event WinInet) to work using existing windows socket?
Here are a few options for implementing the SSL protocol with access through VB6/COM interfaces.
Expose COM interfaces around .NET Framework custom code and libraries for encryption and then call your .NET created COM interfaces from your VB6 application.
Utilize an off-the-shelf component that already has the SSL protocol implemented for you.
Implement the full SSL specification in VB6
After clarification about the need to use an "existing windows socket" I'll update the answer with more details.