muench-develops.FeatureToggler is a lightweight, extensible library for managing feature flags in .NET applications. It supports multiple providers (in-memory, JSON, environment variables, configuration) and integrates seamlessly with ASP.NET Core.

• Multiple Providers: In-Memory, JSON, Environment Variables, Configuration.
• ASP.NET Core Integration: Middleware and Dependency Injection support.
• Thread-Safe: Concurrent updates handled efficiently.
• Testable: Clean design for easy unit testing.
• Extensible: Add custom providers effortlessly.

Install FeatureToggler via NuGet:

dotnet add package muench-develops.FeatureToggler

Add providers in your Program.cs or Startup.cs:

builder.Services.AddFeatureFlags(
    new InMemoryFeatureFlagProvider(
        new[]
        {
            new FeatureFlag("EnableNewUI", true, "Enables the new UI"),
            new FeatureFlag("BetaFeature", false, "Beta feature toggle")
        })
);

Execute actions based on feature flag states:

app.UseFeatureFlag("EnableNewUI",
    onEnabled: () => Console.WriteLine("New UI is enabled!"),
    onDisabled: () => Console.WriteLine("New UI is disabled!"));

app.MapGet("/", (FeatureFlagManager manager) => manager.IsEnabled("EnableNewUI")
        ? Results.Ok("Welcome to the new UI!")
        : Results.Ok("Welcome to the old UI!"));

Check or update feature flags dynamically:

var manager = app.Services.GetRequiredService<FeatureFlagManager>();

if (manager.IsEnabled("EnableNewUI"))
{
    Console.WriteLine("New UI is enabled!");
}

• In-Memory: Simple and fast for development.
• JSON: Load feature flags from a JSON file.
• Environment Variables: Configure flags via environment variables.

We welcome contributions! Please fork the repository and submit a pull request with your changes. For major updates, open an issue first to discuss your ideas.

This project is licensed under the Apache License. See the LICENSE file for details.