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Redis Crashing in .Net 6

I have a weird error in Redis on .Net 6. When I run the test code here:
https://github.com/redis-developer/redis-graph-dotnet-basic-app/blob/main/Program.cs
It works perfectly fine. In this case the code is running in the program.cs file.
When I port that code to a class, in order to better manage encapsulation and complexity. It does not work. What it does is run the code and when it gets to the: await graph.QueryAsync part, it just stops the debugger. Very strange indeed.
Here is the code I am using. Any thoughts or suggestions:
//Program.cs (Relevant Bits)
using RedisTest //PROGRAM //WRITE TO REDIS ENTERPRISE CLOUD Process_LoadGraph process_LoadGraph = new Process_LoadGraph(); process_LoadGraph.Controller(results);
//SHARED CONNECTION CLASS
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using StackExchange.Redis;
namespace RedisTest
{
public class RedisSharedConnection
{
public static ConnectionMultiplexer Connection
{
get
{
return lazyConnection.Value;
}
}
private static Lazy<ConnectionMultiplexer> lazyConnection = new Lazy<ConnectionMultiplexer>(() =>
{
ConnectionMultiplexer connectionMultiplexer = ConnectionMultiplexer.Connect(ConfigData.dbConnectionString);
return connectionMultiplexer;
});
}
}
//USAGE CLASS
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using NRedisGraph;
namespace RedisTest
{
public class Process_LoadGraph
{
public async void Controller(List<Result> results)
{
//Setup
var redisConnection = RedisSharedConnection.Connection;
//var redisConnection = ConnectionMultiplexer.Connect(ConfigData.dbConnectionString);
var db = redisConnection.GetDatabase(ConfigData.dbId);
var graph = new RedisGraph(db);
string graphName = ConfigData.graphName;
//Test Transaction
// Create Bob
// CRASHES HERE
var createBobResult = await graph.QueryAsync("pets", "MERGE(:human{name:'Bob',age:32})");
}
}
}

Turns out the solution is to use Redis in a static class. Along the following lines:
internal static class WriteToDB
{
public static async Task WriteAsync(List<string> querieS)
{
//Load Graph
//Setup
var redisConnection = RedisSharedConnection.Connection;
//var redisConnection = ConnectionMultiplexer.Connect(ConfigData.dbConnectionString);
var db = redisConnection.GetDatabase(ConfigData.dbId);
var graph = new RedisGraph(db);
string graphName = ConfigData.graphName;
// ** DEBUG
//Test Transaction
// Create Bob
var createBobResult = await graph.QueryAsync("pets", "MERGE(:human{name:'Bob',age:32})");
{ }
//Clear Graph
await graph.QueryAsync(graphName, "MATCH(n) DETACH DELETE n");
{ }
}
}

SignalR only works the first time it is called

I have a ASP.NET Core MVC 5 website. I am using SignalR to send "Notifications" from the model layer to the client / view.
If I open my index page, It uses SignalR to send a list of available cameras as they are discovered. I then again use SignalR to send images that the camera is taking on a different model. However, only the first one works.
If I navigate to https://localhost:44303/camera/live/?IP=192.168.50.212 It starts sending images, but will not discover other cameras. If I navigate to the discovery first, the discovery works just fine.
In both the models, the line Hub.Clients.All.SendAsync("method", data); is executing. In both models, the Hub is defined as
public Microsoft.AspNetCore.SignalR.IHubContext<MasterHub> Hub { get; internal set; }`
and each model has a separate controller, that sets the hub context like so:
private readonly IHubContext<MasterHub> _hubContext;
public CameraController(IHubContext<MasterHub> hubContext)
{
_hubContext = hubContext;
}
However, only the first one I navegate to works.
Do I have to close the SignalR connection after sending a message to use it again? If so, How would I do this?
both controllers look like:
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.SignalR;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using Thermal_Screening.Hubs;
using Thermal_Screening.Models;
namespace Thermal_Screening.Controllers
{
public class CameraController : Controller
{
public string CameraName;
private readonly IHubContext<MasterHub> _hubContext;
public CameraController(IHubContext<MasterHub> hubContext)
{
_hubContext = hubContext;
}
public IActionResult Live(string IP)
{
CameraName = getCameraNameFromIP(IP); // doin it this way causes a 2s delay, should get ip in model
return View(new CameraViewModel(IP) { Hub = _hubContext, IP = IP, CameraName = CameraName });
}
public IActionResult Settings(string IP)
{
CameraName = getCameraNameFromIP(IP);
return View(new CameraViewModel(IP) { Hub = _hubContext, IP = IP, CameraName = CameraName });
}
public IActionResult Log(string IP)
{
CameraName = getCameraNameFromIP(IP);
return View(new CameraViewModel(IP) { Hub = _hubContext, IP = IP, CameraName = CameraName });
}
private string getCameraNameFromIP(string IP)
{
WebClient x = new WebClient();
string source = x.DownloadString("http://" + IP);
return Regex.Match(source, #"\<title\b[^>]*\>\s*(?<Title>[\s\S]*?)\</title\>", RegexOptions.IgnoreCase).Groups["Title"].Value;
}
}
}
both viewmodels look like:
using Microsoft.AspNetCore.Http;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http.Extensions;
using Flir.Atlas.Live.Discovery;
using Flir.Atlas.Live.Device;
using Flir.Atlas.Live;
using System.IO;
using Flir.Atlas.Image;
using System.Drawing;
using Microsoft.AspNetCore.SignalR;
using Thermal_Screening.Hubs;
namespace Thermal_Screening.Models
{
public class CameraViewModel
{
public Microsoft.AspNetCore.SignalR.IHubContext<MasterHub> Hub { get; internal set; }
//removed for berevity
Hub.Clients.All.SendAsync("method", "data");

WCF: How can I reach an instance of a service from inside an instance of a service library?

I have a long-running WCF service hosted in a Windows service. I have a service library whose purpose is to report on the state of the service. How can I get to the instance of the service from inside an instance of the service library?
To illustrate, I created a service that records the time it started, and exposes a method to report how long it's been running. The service library needs to be able to call the service's ElapsedSeconds() method, so the the library needs a reference to the running service.
I thought I could use OperationContext.Current. Here's my service library class:
using System;
using System.Collections.Generic;
using System.Linq;
using System.ServiceModel;
using System.Text;
using System.Threading.Tasks;
namespace TimerService
{
public class TimerServiceLib : ITimerServiceLib
{
TheTimerService m_timerService;
public TimerServiceLib()
{
var currentContext = OperationContext.Current;
var instanceContext = currentContext.InstanceContext;
m_timerService = (TheTimerService)instanceContext.GetServiceInstance();
}
public double SecondsSinceStart()
{
return m_timerService.ElapsedSeconds();
}
}
}
But the call to GetServiceInstance() creates a new instance of TimerServiceLib(), which of course gives me an infinite loop. So, what is the correct way to do this?
Here is my service class, actually being hosted in a console application:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.ServiceModel;
using System.ServiceModel.Description;
using System.ServiceProcess;
using System.Text;
using System.Threading.Tasks;
namespace TimerService
{
public partial class TheTimerService : ServiceBase
{
private DateTime m_startTime;
ServiceHost m_svcHost;
public TheTimerService()
{
InitializeComponent();
Init();
m_startTime = DateTime.Now;
}
public double ElapsedSeconds()
{
return (DateTime.Now - m_startTime).TotalSeconds;
}
protected override void OnStart(string[] args)
{
}
protected override void OnStop()
{
}
public void Init()
{
if (m_svcHost != null)
{
m_svcHost.Close();
}
string httpAddress = "http://localhost:1234/TimerService";
string tcpAddress = "net.tcp://localhost:1235/TimerService";
Uri[] adrbase = { new Uri(httpAddress), new Uri(tcpAddress) };
m_svcHost = new ServiceHost(typeof(TimerServiceLib), adrbase);
ServiceMetadataBehavior mBehave = new ServiceMetadataBehavior();
m_svcHost.Description.Behaviors.Add(mBehave);
var debugBehavior = m_svcHost.Description.Behaviors.Find<ServiceDebugBehavior>();
debugBehavior.IncludeExceptionDetailInFaults = true;
BasicHttpBinding httpBinding = new BasicHttpBinding();
m_svcHost.AddServiceEndpoint(typeof(ITimerServiceLib), httpBinding, httpAddress);
m_svcHost.AddServiceEndpoint(typeof(IMetadataExchange),
MetadataExchangeBindings.CreateMexHttpBinding(), "mex");
NetTcpBinding tcpBinding = new NetTcpBinding();
m_svcHost.AddServiceEndpoint(typeof(ITimerServiceLib), tcpBinding, tcpAddress);
m_svcHost.AddServiceEndpoint(typeof(IMetadataExchange),
MetadataExchangeBindings.CreateMexTcpBinding(), "mex");
m_svcHost.Open();
// SimShopServiceLib.m_shop = new CSimShopManager();
}
}
}

You can do it this way:
First, modify your TimerServiceLib and do the constructor injection of TheTimerService:
public class TimerServiceLib : ITimerServiceLib
{
private readonly TheTimerService m_timerService;
public TimerServiceLib(TheTimerService theTimerService)
{
m_timerService = theTimerService;
}
public double SecondsSinceStart()
{
return m_timerService.ElapsedSeconds();
}
}
Then, in your Init() upon creation of ServiceHost, instantiate first your service and pass the TheTimerService. Since your are creating the ServiceHost inside your windows service, wich is TheTimerService you can pass this.
Uri[] adrbase = { new Uri(httpAddress), new Uri(tcpAddress) };
var timerServiceLib = new TimerServiceLib(this)
m_svcHost = new ServiceHost(timerServiceLib , adrbase);
For more details about passing object in you service see this link.
Disclaimer : The above code is not tested.

.NET Remoting: Exception "Value NULL" at RegisterWellKnownServiceType

I'm new at .NET remoting and C#. I need a client/server application and want to handle this with .NET Remoting. I've wrote a class library for the remoting object, the EchoServer class, with some test methods.
The class library I've added to my server project in Visual Studio. The assembly "System.Runtime.Remoting" I've added, too.
The following is the code of my server:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;
using Remoting; //Namespace Lib
namespace Server
{
public partial class Server : Form
{
public Server()
{
InitializeComponent();
TcpChannel serverChannel = null;
try
{
serverChannel = new TcpChannel(9998);
lvStatus.Items.Add("Server is listening on port 8089...");
string strIn = "";
ChannelServices.RegisterChannel(serverChannel, true);
RemotingConfiguration.RegisterWellKnownServiceType(Type.GetType("Remoting.EchoServer, remoting_dll"), "Echo", WellKnownObjectMode.SingleCall);
}
catch (Exception ex)
{
ChannelServices.UnregisterChannel(serverChannel);
MessageBox.Show(ex.Message.ToString());
}
}
}
}
If I start the server, I will get an exception:
The value cannot be NULL
Parametername: type
I've tried some other code of a tutorial, but I will get the same excetion, equal if the class for the remoting object is implented as a class library or it is as a class directly in my project.

Can you post implementation of Remoting?
I thing that your mistake is next:
"Remoting.EchoServer, remoting_dll"
So, you should use Type.GetType correctly.
Example of working code:
static void Main(string[] args)
{
Server();
}
static void Server()
{
Console.WriteLine("Server started...");
var httpChannel = new HttpChannel(9998);
ChannelServices.RegisterChannel(httpChannel);
RemotingConfiguration.RegisterWellKnownServiceType(Type.GetType("Server.Program+SomeClass"), "SomeClass", WellKnownObjectMode.SingleCall);
Console.WriteLine("Press ENTER to quit");
Console.ReadLine();
}
public interface ISomeInterface
{
string GetString();
}
public class SomeClass : MarshalByRefObject, ISomeInterface
{
public string GetString()
{
const string tempString = "ServerString";
Console.WriteLine("Server string is sended: {0}", tempString);
return tempString;
}
}

How to properly use SPServiceApplicationCollection?

I am trying to write a little console app to display a list of running Service Applications on a SharePoint 2010 site. I have employed Microsoft.SharePoint as well as Microsoft.SharePoint.Administration, but so far I am not having much luck. Below is what I have been fiddling around with. Can anyone give me some pointers on how to properly use SPServiceApplicationCollection?
Thanks in advance!
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel;
using System.ServiceProcess;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
SPServiceApplicationCollection services = new SPServiceApplicationCollection(String, SPFarm.Local.Services);
foreach (SPServiceApplication service in services)
{
Console.WriteLine(service.Name);
if (service is SPWebService)
{
SPWebService webService = (SPWebService)service;
foreach (SPWebApplication webApp in webService.WebApplications)
{
Console.WriteLine(webApp.Name);
Console.ReadLine();
}
}
}
}
}
}
EDIT
After some digging/asking around I came up with a rough solution of what I wanted.
For future reference/anyone else that wishes to do this sort of thing, I was able to get a list of deployed servers as well as the application name by doing the following:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel;
using System.ServiceProcess;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;
using Microsoft.SharePoint.Administration.Health;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
var solution = SPFarm.Local.Solutions["Your Service Application Name.wsp"];
string serverName = string.Empty;
foreach (SPServer server in solution.DeployedServers)
{
serverName += server.Name;
Console.WriteLine(server.Name);
}
if (solution != null)
{
if (solution.Deployed)
{
Console.WriteLine("{0} is currently deployed on: {1}", solution.Name, serverName);
Console.ReadLine();
}
else
{
Console.WriteLine("Error! Solution not deployed!");
Console.ReadLine();
}
}
}
}
}

After some digging/asking around I came up with a rough solution of what I wanted. For future reference/anyone else that wishes to do this sort of thing, I was able to get a list of deployed servers as well as the application name by doing the following:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel;
using System.ServiceProcess;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;
using Microsoft.SharePoint.Administration.Health;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
var solution = SPFarm.Local.Solutions["Your Service Application Name.wsp"];
string serverName = string.Empty;
foreach (SPServer server in solution.DeployedServers)
{
serverName += server.Name;
Console.WriteLine(server.Name);
}
if (solution != null)
{
if (solution.Deployed)
{
Console.WriteLine("{0} is currently deployed on: {1}", solution.Name, serverName);
Console.ReadLine();
}
else
{
Console.WriteLine("Error! Solution not deployed!");
Console.ReadLine();
}
}
}
}
}