Tag: .NET

To generate a SonarQube token (required for authentication when running analyses from the command line or CI/CD pipelines), follow these steps:

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Steps to Generate a SonarQube Token

1. Log in to your SonarQube server (e.g., http://localhost:9000 for local setups).
2. Click your profile icon (top-right corner) → “My Account”.
3. Go to the “Security” tab.
4. Under “Tokens”, enter a name for your token (e.g., vs-console-token).
5. Click “Generate”.
6. Copy the token immediately (it won’t be shown again!).
   Example token format: sqp_1234567890abcdef

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How to Use the Token

• In dotnet-sonarscanner commands, pass the token via:shCopyDownloaddotnet sonarscanner begin /k:”your-project-key” /d:sonar.host.url=”http://localhost:9000″ /d:sonar.login=”sqp_1234567890abcdef”
• For security, never hardcode the token in scripts. Use:
  • Environment variables (e.g., SONAR_TOKEN).
  • Secret management tools (e.g., Azure Key Vault, GitHub Secrets).

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Important Notes

• 🔒 Treat tokens like passwords (they grant access to your SonarQube projects).
• 🔄 Regenerate tokens periodically or revoke old ones (under “Security”).
• 🚫 No token? You’ll get errors like Not authorized or Authentication failed.

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Example Workflow

# Set token as an environment variable (optional)
set SONAR_TOKEN=sqp_1234567890abcdef

# Run analysis (Windows CMD)
dotnet sonarscanner begin /k:"my-project" /d:sonar.host.url="http://localhost:9000" /d:sonar.login="%SONAR_TOKEN%"
dotnet build
dotnet sonarscanner end /d:sonar.login="%SONAR_TOKEN%"

Get the SonarQube Project URL

The project URL is the web address of your project in SonarQube. It typically follows this format:

http://<sonarqube-server-url>/dashboard?id=<project-key>

• <sonarqube-server-url>: The host where SonarQube is running (e.g., http://localhost:9000 if running locally).
• <project-key>: The unique key assigned to your project in SonarQube.

How to Find the Project Key?

1. Log in to your SonarQube server.
2. Navigate to your project.
3. Check the URL in the browser’s address bar (e.g., http://localhost:9000/dashboard?id=my-project-key).
4. Alternatively, go to Project Settings → General Settings → Key.

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2. Run SonarQube Analysis in Visual Studio Console

To analyze a .NET project in Visual Studio Developer Command Prompt (or terminal), use the SonarScanner for .NET (dotnet-sonarscanner).

Prerequisites

• Install Java (required for SonarQube scanner).
• Install SonarScanner for .NET:shCopyDownloaddotnet tool install –global dotnet-sonarscanner

Steps to Run Analysis

1. Start the SonarQube Analysis:shCopyDownloaddotnet sonarscanner begin /k:”” /d:sonar.host.url=”” /d:sonar.login=”“
   • Replace:
     • <project-key> with your SonarQube project key.
     • <sonarqube-server-url> with your SonarQube server URL (e.g., http://localhost:9000).
     • <token> with a SonarQube user token.
2. Build Your Project:shCopyDownloaddotnet build
3. Complete & Publish Results to SonarQube:shCopyDownloaddotnet sonarscanner end /d:sonar.login=”<token>”
4. Check Results:
   • Open the SonarQube project URL (e.g., http://localhost:9000/dashboard?id=my-project-key) in a browser.

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Example

# Start analysis
dotnet sonarscanner begin /k:"my-dotnet-app" /d:sonar.host.url="http://localhost:9000" /d:sonar.login="sqp_1234567890abcdef"

# Build the project
dotnet build

# End analysis & upload results
dotnet sonarscanner end /d:sonar.login="sqp_1234567890abcdef"

After running these commands, your analysis results will appear in the SonarQube dashboard.

Integrating Azure Application Insights in a Blazor WebAssembly (WASM) app is possible, though it requires special handling since Blazor WASM runs entirely in the browser, and you can’t use the full .NET SDK for Application Insights like you can in server-side apps.

Here’s how you can set it up using JavaScript SDK (since Blazor WASM ultimately runs in the browser):

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✅ Step-by-Step Guide

1. Create Application Insights Resource (if not done)

• Go to Azure Portal → Create a resource → Application Insights.
• Choose General → Application Insights, select region, etc.
• After creation, copy the Instrumentation Key or Connection String.

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2. Add the Application Insights JavaScript SDK

In your Blazor WebAssembly project:

Modify wwwroot/index.html (for standalone Blazor WASM)

htmlCopyEdit<!-- Application Insights JavaScript SDK -->
<script type="text/javascript">
  var appInsights = window.appInsights || function (config) {
    function r(config) {
      t[config] = function () {
        var i = arguments;
        t.queue.push(function () { t[config].apply(t, i); })
      }
    }
    var t = { config: config }, u = document, e = window, o = "script", s = u.createElement(o), i, f;
    for (s.src = config.url || "https://az416426.vo.msecnd.net/scripts/a/ai.0.js", u.getElementsByTagName(o)[0].parentNode.appendChild(s), t.cookie = u.cookie, t.queue = [], i = ["Event", "Exception", "Metric", "PageView", "Trace", "Dependency"]; i.length;)
      r("track" + i.pop());
    return r("setAuthenticatedUserContext"), r("clearAuthenticatedUserContext"), r("flush"), config.disableExceptionTracking || (i = "onerror", r("_" + i), f = e[i], e[i] = function (config, r, u, e, o) {
      var s = f && f(config, r, u, e, o);
      return s !== !0 && t["_" + i](config, r, u, e, o), s
    }), t
  }({
    instrumentationKey: "YOUR_INSTRUMENTATION_KEY"
  });

  window.appInsights = appInsights;
  appInsights.trackPageView();
</script>

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3. Call App Insights from C# Code

You can invoke JavaScript from your Blazor C# code like this:

Create a service to interact with JS (e.g., AppInsightsService.cs):

csharpCopyEditusing Microsoft.JSInterop;
using System.Threading.Tasks;

public class AppInsightsService
{
    private readonly IJSRuntime _jsRuntime;

    public AppInsightsService(IJSRuntime jsRuntime)
    {
        _jsRuntime = jsRuntime;
    }

    public async Task TrackEventAsync(string eventName)
    {
        await _jsRuntime.InvokeVoidAsync("appInsights.trackEvent", new { name = eventName });
    }

    public async Task TrackExceptionAsync(string errorMessage)
    {
        await _jsRuntime.InvokeVoidAsync("appInsights.trackException", new
        {
            exception = new { message = errorMessage }
        });
    }

    public async Task TrackPageViewAsync(string pageName)
    {
        await _jsRuntime.InvokeVoidAsync("appInsights.trackPageView", new { name = pageName });
    }
}

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4. Register the Service

In Program.cs:

csharpCopyEditbuilder.Services.AddScoped<AppInsightsService>();

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5. Use in Your Components

razorCopyEdit@inject AppInsightsService AppInsights

<button @onclick="TrackEvent">Track Event</button>

@code {
    private async Task TrackEvent()
    {
        await AppInsights.TrackEventAsync("ButtonClicked");
    }
}

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🧠 Notes

• Only client-side telemetry will be captured (JS-side) — no automatic dependency tracking, for example.
• If you need full telemetry, consider combining it with Blazor WASM hosted model and using Application Insights server SDK in the backend.

ConfigureAwait(false) is a C# feature used with async and await to control how the continuation of an async method is scheduled after an awaited operation completes.

Here’s a breakdown of when and why you might need to call ConfigureAwait(false):

Understanding Synchronization Context

• What it is: A synchronization context (System.Threading.SynchronizationContext) represents a way to queue work (continuations) to a specific thread or threads.
  • UI Applications (WinForms, WPF, Xamarin, old ASP.NET on .NET Framework): These have a UI thread. Operations that update the UI must run on this specific UI thread. The synchronization context ensures that continuations after an await (if it wasn’t configured otherwise) are posted back to this UI thread.
  • ASP.NET Core: By default, ASP.NET Core does not have a synchronization context that behaves like the UI one. It uses a more efficient internal mechanism for managing requests.
  • Console Apps / Library Code (typically): Often have no special synchronization context, or they use the default thread pool context.
• How await uses it: When you await a Task, by default (without ConfigureAwait(false)), the runtime captures the current SynchronizationContext (if one exists) and the current TaskScheduler. When the awaited task completes, it attempts to post the remainder of the async method (the continuation) back to that captured context or scheduler.

When You SHOULD GENERALLY Use ConfigureAwait(false)

1. Library Code (Most Common and Important Case):
   • If you are writing a general-purpose library (e.g., a NuGet package, a shared business logic layer, a data access layer) that is not specific to any UI framework or ASP.NET Core.Reason: Your library code doesn’t know what kind of application will call it. If it’s called from an application with a restrictive synchronization context (like a UI app), and your library’s async methods always try to resume on that captured context, it can lead to:
     • Performance Issues: Unnecessary context switching back to the UI thread for non-UI work.Deadlocks: Especially if the calling code is blocking on the async method (e.g., using .Result or .Wait(), which is an anti-pattern but can happen). The UI thread might be blocked waiting for your library method to complete, while your library method is waiting to get back onto the UI thread to complete. This is a classic deadlock.
     Solution: Use ConfigureAwait(false) on all (or almost all) await calls within your library. This tells the runtime, “I don’t need to resume on the original context; any available thread pool thread is fine.”

// In a library
public async Task<string> GetDataAsync()
{
    // _httpClient is an HttpClient instance
    var response = await _httpClient.GetStringAsync("some_api_endpoint")
                                  .ConfigureAwait(false); // Don't need original context

    // Process the response (doesn't need original context)
    var processedData = Process(response); 

    await Task.Delay(100).ConfigureAwait(false); // Another example

    return processedData;
}
}

When You MIGHT NOT NEED ConfigureAwait(false) (or when ConfigureAwait(true) is implied/desired)

1. Application-Level Code in UI Applications (e.g., event handlers, view models directly interacting with UI):
   • If the code after an await needs to interact directly with UI elements (e.g., update a label, change a button’s state).Reason: You want the continuation to run on the UI thread’s synchronization context. This is the default behavior, so explicitly using ConfigureAwait(true) is redundant but not harmful. Omitting ConfigureAwait achieves the same.

// In a UI event handler (e.g., WPF, WinForms)
private async void Button_Click(object sender, RoutedEventArgs e)
{
    MyButton.IsEnabled = false; // UI update
    var data = await _myService.FetchDataAsync(); // This service call might use ConfigureAwait(false) internally
    // The continuation here will be back on the UI thread by default
    MyLabel.Text = data; // UI update
    MyButton.IsEnabled = true; // UI update
}

1. Application-Level Code in ASP.NET Core (e.g., Controllers, Razor Pages, Middleware):
   • Generally, not strictly needed: ASP.NET Core doesn’t have a SynchronizationContext that causes the same deadlock problems as UI frameworks or older ASP.NET. HttpContext and related services are accessible without needing to be on a specific “request thread” in the same way UI elements need the UI thread.
   • However, some developers still apply ConfigureAwait(false) out of habit or for consistency if their codebase also includes library projects where it is critical. It typically doesn’t hurt in ASP.NET Core and might offer a micro-optimization by avoiding an unnecessary check for a context.
   • If you do rely on HttpContext (e.g., HttpContext.User) after an await, ensure your understanding of its flow. In ASP.NET Core, HttpContext is generally available to continuations regardless of ConfigureAwait, but being explicit about context requirements is never a bad idea.
2. Console Applications:
   • Usually, console applications don’t have a restrictive SynchronizationContext (they use the thread pool context). So, ConfigureAwait(false) is often not strictly necessary for preventing deadlocks.
   • However, if the console app uses libraries that might install a custom SynchronizationContext, or if you are writing code that might be reused in other contexts, using ConfigureAwait(false) can still be a good defensive measure.

Summary Table:

Context	Recommendation for ConfigureAwait(false)	Reason
General-Purpose Library Code	Strongly Recommended (Use it)	Prevent deadlocks, improve performance when called from context-sensitive environments (e.g., UI).
UI Application Code (Event Handlers, VMs)	Generally Not Needed (Default is fine)	You often need to return to the UI thread for UI updates.
ASP.NET Core Application Code	Optional / Good Practice	No UI-like SynchronizationContext causing deadlocks. Can be a micro-optimization or for consistency.
Console Application Code	Optional / Good Practice	Usually no restrictive context, but good for reusability or if custom contexts are involved.

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Key Takeaway:

The most critical place to use ConfigureAwait(false) is in library code to make it robust and performant regardless of the calling application’s environment. In application-level code, the necessity depends on whether you need to return to a specific context (like the UI thread).

As of current date (May 16, 2025), this guidance remains standard practice in the .NET ecosystem.