.Net Application Database Connection Failure

[sgussy]

Hello,

I just developed a .Net Application that queried the GeoSCADA database via an Advanced Connection and published to a remote MySQL Database and it was successful.

I am replicating that project, except it will publish to a database via an API call.  The only difference is the first app was GeoSCADA 2020 and this project is ClearSCADA 2017 R3. 

I have confirmed that 127.0.0.1 connects to the server on the local machine and that the port is 5481 so i don't think the ServerNode object is the issue.  

The only glaring difference I see is that in the first project the line:

AdvConnection = node.Connect("Utility"); was AdvConnection = node.Connect("Utility", false);

For some reason in this project, it will only allow me to provide the clientName.  Trying to add the False gives an error.

So the program is not erroring, but is instead not connecting the Database. ie, the Try...Catch... Code at the bottom.

PROJECT CODE BELOW: (Only to the Catch that is throwing the "Cannot Connect...."

using System;
using System.IO;
using System.Data;
using System.Threading.Tasks;
using ClearScada.Client;
using ClearScada.Client.Advanced;

namespace SCADA_API_Console_App
{
	static class Program
	{
		// Global node and Geo SCADA server connection -- using ClearScada.Client.Advanced;
		private static ServerNode node;
		private static IServer AdvConnection;

		/// <summary>
		/// Program to query and publish data from the GeoSCADA database via API Call
		/// </summary>
		/// <param name="args"></param>
		/// <returns></returns>

		async static Task Main(string[] args)
		{
			//Create
			StreamWriter LogFiler = new StreamWriter(@"C:\SCADA_VS_Apps\SCADA_API_Console_Logfile.txt", append: true);
			LogFiler.WriteLine(DateTime.Now + ": Logger Initiated.");

			// Geo SCADA Connection
			node = new ServerNode(ClearScada.Client.ConnectionType.Standard, "127.0.0.1", 5481);
			try
			{
				AdvConnection = node.Connect("Utility");
			}
			catch
			{
				LogFiler.WriteLine(DateTime.Now + ": Cannot connect to Geo SCADA - Advanced Connection Failure");
				LogFiler.WriteLine("!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");
				LogFiler.WriteLine(" ");
				LogFiler.Close();
				Console.WriteLine("Cannot connect to Geo SCADA");
				return;
			}

[sgussy]

I should also note that it appears, i am using .Net 5.0 on the new project where the old project used .Net 4.7.2. 

These are two different servers/clients.

@sbeadle I see you're quite active on here and have used your github for reference in the past, maybe you have seen this before.  I am very confused why the node won't allow the false when every example contains it.

[BevanWeiss]

There's going to be a few things in play.

1. Client<->Server compatibility.  https://community.se.com/t5/Geo-SCADA-Knowledge-Base/Geo-SCADA-and-ClearSCADA-Version-Compatibility-...
   From this it seems that Geo SCADA Expert 2020 client should be compatible back to ClearSCADA 2017R3.
2. Client DLL version vs your application ABI
   The best option here is to ship the client DLLs alongside your application.  In this way whilst you're always using a fixed client version, it is one that you have validated with your application.  If you don't do this, and allow for the Windows DLL resolution stuff.. you'll want to make sure that the client has a matching version of the DLL that will work with the expected ABI of your application (i.e. the same call signatures.. which sounds like is not the case for your situation).
3. .NET... I'm unaware of .NET 5 being at all backward compatible with .NET FRAMEWORK 4.x  This is important to note that there are numerous forms of .NET, and they are generally all incompatible.  i.e. .NET Framework 1.5 and .NET Framework 3.5 are entirely different.. I'm pretty sure once into the .NET Framework 4.x series there is backwards compatibility, but .NET Core is entirely different again (with .NET Core 1 and .NET Core 2 being incompatible).. .NET 5.0 is supposed to be where they are unifying the various versions... so .NET Framework concepts are being brought into .NET Core.. but I suspect this is going to result in another incompatible ABI where .NET 5 will not be compatible with any .NET Core, or any .NET Framework.
   Since Geo SCADA Expert 2020 is built against .NET 4.7.1 (I think) you should be able to go with any later release in the .NET Framework 4.x.x family (i.e. .NET Framework 4.8.2 etc)

[sbeadle]

Firstly - what Bevan wrote.

Plus:

* Very occasionally the API changes, which explains the change of arguments to Connect

* Your code did not print the exception message which can be useful to understand the problem. (catch (exception e) ... writeline( e.message ...

Steve