3.5.0

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 3.5.0
• Microsoft.FeatureManagement.AspNetCore 3.5.0

Microsoft.FeatureManagement

• No changes in this release.

Microsoft.FeatureManagement.AspNetCore

• Updated Microsoft.FeatureManagement reference to 3.5.0.

Enhancements

• Introduced an overloaded extension method WithTargeting() for ASP.NET Core applications. It registers a default ITargetingContextAccessor that constructs user context based on the authenticated user of a request. #466

4.0.0-preview4

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 4.0.0-preview4
• Microsoft.FeatureManagement.AspNetCore 4.0.0-preview4
• Microsoft.FeatureManagement.Telemetry.ApplicationInsights 4.0.0-preview4

Microsoft.FeatureManagement

Enhancements

• The feature flag telemetry pipeline is now integrated with .NET Acitivity instrumentation. Feature manager now has an AcitvitySource called "Microsoft.FeatureManagement". If telemetry is enabled for a feature flag, whenever the feature flag is evaluated, feature manager will start an Activity and add an ActivityEvent with tags containing feature evaluation information. #455

Breaking Changes

• If you were using earlier preview versions of this package and configuration files to define variant feature flags, they are no longer supported in the .NET Feature Management schema. Instead, please use the Microsoft Feature Management schema to define variant feature flags. #421.

• AddTelemetryPublisher API and ITelemetryPublisher interface were removed. The feature flag telemetry pipeline is now integrated with .NET Acitivity instrumentation. #455

Microsoft.FeatureManagement.AspNetCore

• Updated Microsoft.FeatureManagement reference to 4.0.0-preview4.

Microsoft.FeatureManagement.Telemetry.ApplicationInsights

• Updated Microsoft.FeatureManagement reference to 4.0.0-preview4.

Enhancements

• Introduced a new API AddApplicationInsightsTelemetryPublisher to register a feature flag telemetry publisher for Application Insights. #455

  builder.Services.AddFeatureManagement()
                  .WithTargeting()
                  .AddApplicationInsightsTelemetryPublisher();

Breaking Changes

• The TargetingTelemetryInitializer type has been moved to this package from the now-deprecated Microsoft.FeatureManagement.Telemetry.ApplicationInsights.AspNetCore package. This change simplifies the utilization of feature flag telemetry.

• The type ApplicationInsightsTelemetryPublisher has been removed as its functionality has been replaced with the new API AddApplicationInsightsTelemetryPublisher for publishing feature flag telemetry to Application Insights. #455

3.4.0

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 3.4.0
• Microsoft.FeatureManagement.AspNetCore 3.4.0

Microsoft.FeatureManagement

Enhancements

• All public classes no longer use init-only setters, ensuring compatibility with application using C# 7 or earlier. #450

Microsoft.FeatureManagement.AspNetCore

• Updated Microsoft.FeatureManagement reference to 3.4.0.

3.3.1

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 3.3.1
• Microsoft.FeatureManagement.AspNetCore 3.3.1

Microsoft.FeatureManagement

Bug fixes

• Fixed a bug that TimeWindowFilter would be registered repeatedly when calling AddFeatureFilter<TimeWindowFilter> after the call of AddFeatureManagement(). #447

Microsoft.FeatureManagement.AspNetCore

• Updated Microsoft.FeatureManagement reference to 3.3.1.

3.3.0

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 3.3.0
• Microsoft.FeatureManagement.AspNetCore 3.3.0

Microsoft.FeatureManagement

Enhancements

• Added a Recurrence option to the TimeWindow filter to support recurring time window. This enables scenarios where a feature flag is activated based on a recurrence pattern, such as every day after 5 PM or every Friday. See more details here. (#266)
• A LoggerFactory is no longer required when constructing built-in filters. (#386)

Bug fixes

• Fixed a possible null-reference exception when enumerating GetFeatureNamesAsync. (#438)

Microsoft.FeatureManagement.AspNetCore

• Updated Microsoft.FeatureManagement reference to 3.3.0.

4.0.0-preview3

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 4.0.0-preview3
• Microsoft.FeatureManagement.AspNetCore 4.0.0-preview3
• Microsoft.FeatureManagement.Telemetry.ApplicationInsights 4.0.0-preview3
• Microsoft.FeatureManagement.Telemetry.ApplicationInsights.AspNetCore 4.0.0-preview3

Microsoft.FeatureManagement

Enhancements

• Added support for variant feature flags defined using Microsoft Feature Management schema. Variants and telemetry can be declared using Microsoft Feature Flag schema v2. The Microsoft Feature Management schema is designed to be language agnostic, enabling you to apply a consistent feature management configuration across Microsoft feature management libraries of different programming languages.

Microsoft.FeatureManagement.AspNetCore

• Updated Microsoft.FeatureManagement reference to 4.0.0-preview3.

Microsoft.FeatureManagement.Telemetry.ApplicationInsights

Breaking Changes

• Updated the namespace for ApplicationInsightsTelemetryPublisher to Microsoft.FeatureManagement.Telemetry. In the future, developers using any of our offered telemetry publishers will no longer need to specify the service specific namespaces like using Microsoft.FeatureManagement.Telemetry.ApplicationInsights.

• Updated the namespace for TrackEvent extension method of TelemetryClient to Microsoft.ApplicationInsights. The previous directive using Microsoft.FeatureManagement.Telemetry.ApplicationInsights is no longer required when calling the TrackEvent method.

Microsoft.FeatureManagement.Telemetry.ApplicationInsights.AspNetCore

• Updated Microsoft.FeatureManagement reference to 4.0.0-preview3.

4.0.0-preview2

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 4.0.0-preview2
• Microsoft.FeatureManagement.AspNetCore 4.0.0-preview2
• Microsoft.FeatureManagement.Telemetry.ApplicationInsights 4.0.0-preview2
• Microsoft.FeatureManagement.Telemetry.ApplicationInsights.AspNetCore 4.0.0-preview2

Microsoft.FeatureManagement

Enhancements

• Added support for variant feature flag-based service provider in dependency injection. It allows different service implementations to be injected automatically for different targeted audiences based on their variant assignment. (#39). See more details here.
• Added a TargetingContext property to the EvaluationEvent. This allows feature evaluation events to accurately represent what the targeting context was at the time of feature evaluation. (#409)

Microsoft.FeatureManagement.AspNetCore

Enhancements

• Introduced a new ASP.NET Core middleware called TargetingHttpContextMiddleware. It makes targeting information available from HttpContext on each request. (#409)
• Added support for .NET 8 target framework. (#364)

Microsoft.FeatureManagement.Telemetry.ApplicationInsights

Enhancements

• Added a TargetingId property to the feature evaluation events sent to Application Insights. The TargetingId is the identifier of a targeted user during feature evaluation. This new property allows you to correlate feature evaluation events with other telemetry data your application sends to Application Insights, as long as they share the same TargetingId. (#409)

Microsoft.FeatureManagement.Telemetry.ApplicationInsights.AspNetCore

Enhancements

• Introduced a telemetry initializer named TargetingTelemetryInitializer. It automatically adds targeting information to telemetry data your application sends to Application Insights. This can be used to correlate your telemetry data with feature evaluation events based on the targeting information during your telemetry analysis. (#409)

3.2.0

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 3.2.0
• Microsoft.FeatureManagement.AspNetCore 3.2.0

Enhancements

• Added support for feature flags defined using Microsoft Feature Management schema

4.0.0-preview

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 4.0.0-preview
• Microsoft.FeatureManagement.AspNetCore 4.0.0-preview
• Microsoft.FeatureManagement.Telemetry.ApplicationInsights 4.0.0-preview

Variants

Variants are a tool that can be used to surface different variations of a feature to different segments of an audience. Previously, this library only worked with flags. The flags were limited to boolean values, as they are either enabled or disabled. Variants have dynamic values. They can be string, int, a complex object, or a reference to a ConfigurationSection.

//
// Modify view based off multiple possible variants
Variant variant = await featureManager.GetVariantAsync(MyFeatureFlags.BackgroundUrl);

model.BackgroundUrl = variant.Configuration.Value;

return View(model);

Variants are defined within a Feature, under a new section named "Variants". Variants are assigned by allocation, defined in a new section named "Allocation".

"BackgroundUrl": {
    "Variants": [
        {
            "Name": "GetStarted",
            "ConfigurationValue": "https://learn.microsoft.com/en-us/media/illustrations/biztalk-get-started-get-started.svg"
        },
        {
            "Name": "InstallConfigure",
            "ConfigurationValue": "https://learn.microsoft.com/en-us/media/illustrations/biztalk-host-integration-install-configure.svg"
        }
    ],
    "Allocation": { 
        // Defines Users, Groups, or Percentiles for variant assignment
    }
    // Filters and other Feature fields
}

For more details on Variants, see here.

Telemetry

The feature management library now offers the ability to emit events containing information about a feature evaluation. This can be used to ensure a flag is running as expected, or to see which users were given which features and why they were given the feature. To enable this functionality, two things need to be done:

The flag needs to explicitly enable telemetry in its definition.

"MyFlag": {
    "Telemetry": {
        "Enabled": true
    }
}

And a telemetry publisher needs to be registered. Custom publishers can be defined, but for Application Insights one is already available in the Microsoft.FeatureManagement.Telemetry.ApplicationInsights package. Publishers can be added with a single line.

builder.services
    .AddFeatureManagement()
    .AddTelemetryPublisher<ApplicationInsightsTelemetryPublisher>();

An example is available to demonstrate how to use the new Telemetry in an ASP.NET application. See the example in the examples folder.

For more details on Telemetry, see here.

Additional Changes

IVariantFeatureManager

IVariantFeatureManager has been added as the successor of the existing IFeatureManager. It continues to offer the functions of IFeatureManager, but offers the new GetVariantAsync methods as well.

Cancellation Tokens

IVariantFeatureManager incorporates cancellation tokens into the methods of IFeatureManager. For existing apps to take advantage of cancellation tokens, use the IVariantFeatureManager interface instead and adjust calls to IsEnabledAsync or GetFeatureNamesAsync to include a CancellationToken.

Status field

Status is a new optional field on a Feature that controls how a flag's enabled state is evaluated. Flags can set this field to Disabled. This will cause the flag to always act disabled, while the rest of the defined schema remains intact. See here.

Breaking Changes

There are no breaking changes in this release.

3.1.1

Microsoft.FeatureManagement Updates

The packages associated with this release are

• Microsoft.FeatureManagement 3.1.1
• Microsoft.FeatureManagement.AspNetCore 3.1.1

Bug fix

• Fixed a bug where feature manager will fail to add cache entry if the shared memory cache sets SizeLimit. (#325)