feat: Add Dependency Injection and Hosting support for OpenFeature #310
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,24 @@ | ||
| namespace OpenFeature; | ||
|
|
||
| /// <summary> | ||
| /// Defines the contract for managing the lifecycle of a feature api. | ||
| /// </summary> | ||
| public interface IFeatureLifecycleManager | ||
| { | ||
| /// <summary> | ||
| /// Ensures that the feature provider is properly initialized and ready to be used. | ||
| /// This method should handle all necessary checks, configuration, and setup required to prepare the feature provider. | ||
| /// </summary> | ||
| /// <param name="cancellationToken">Propagates notification that operations should be canceled.</param> | ||
| /// <returns>A Task representing the asynchronous operation of initializing the feature provider.</returns> | ||
| /// <exception cref="InvalidOperationException">Thrown when the feature provider is not registered or is in an invalid state.</exception> | ||
| ValueTask EnsureInitializedAsync(CancellationToken cancellationToken = default); | ||
|
|
||
| /// <summary> | ||
| /// Gracefully shuts down the feature api, ensuring all resources are properly disposed of and any persistent state is saved. | ||
| /// This method should handle all necessary cleanup and shutdown operations for the feature provider. | ||
| /// </summary> | ||
| /// <param name="cancellationToken">Propagates notification that operations should be canceled.</param> | ||
| /// <returns>A Task representing the asynchronous operation of shutting down the feature provider.</returns> | ||
| ValueTask ShutdownAsync(CancellationToken cancellationToken = default); | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,43 @@ | ||
| using Microsoft.Extensions.DependencyInjection; | ||
| using Microsoft.Extensions.Logging; | ||
|
|
||
| namespace OpenFeature.Internal; | ||
|
|
||
| internal sealed partial class FeatureLifecycleManager : IFeatureLifecycleManager | ||
| { | ||
| private readonly Api _featureApi; | ||
| private readonly IServiceProvider _serviceProvider; | ||
| private readonly ILogger<FeatureLifecycleManager> _logger; | ||
|
|
||
| public FeatureLifecycleManager(Api featureApi, IServiceProvider serviceProvider, ILogger<FeatureLifecycleManager> logger) | ||
| { | ||
| _featureApi = featureApi; | ||
| _serviceProvider = serviceProvider; | ||
| _logger = logger; | ||
| } | ||
|
|
||
| /// <inheritdoc /> | ||
| public async ValueTask EnsureInitializedAsync(CancellationToken cancellationToken = default) | ||
| { | ||
| this.LogStartingInitializationOfFeatureProvider(); | ||
| var featureProvider = _serviceProvider.GetService<FeatureProvider>(); | ||
| if (featureProvider == null) | ||
| { | ||
| throw new InvalidOperationException("Feature provider is not registered in the service collection."); | ||
| } | ||
| await _featureApi.SetProviderAsync(featureProvider).ConfigureAwait(false); | ||
|
There was a problem hiding this comment. We might want an optional value for domain, or some other method for working with domain-scoped providers. |
||
| } | ||
|
|
||
| /// <inheritdoc /> | ||
| public async ValueTask ShutdownAsync(CancellationToken cancellationToken = default) | ||
| { | ||
| this.LogShuttingDownFeatureProvider(); | ||
| await _featureApi.ShutdownAsync().ConfigureAwait(false); | ||
| } | ||
|
|
||
| [LoggerMessage(200, LogLevel.Information, "Starting initialization of the feature provider")] | ||
| partial void LogStartingInitializationOfFeatureProvider(); | ||
|
|
||
| [LoggerMessage(200, LogLevel.Information, "Shutting down the feature provider")] | ||
| partial void LogShuttingDownFeatureProvider(); | ||
| } | ||
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,23 @@ | ||
| // @formatter:off | ||
| // ReSharper disable All | ||
| #if NETCOREAPP3_0_OR_GREATER | ||
| // https://github.com/dotnet/runtime/issues/96197 | ||
| [assembly: System.Runtime.CompilerServices.TypeForwardedTo(typeof(System.Runtime.CompilerServices.CallerArgumentExpressionAttribute))] | ||
| #else | ||
| #pragma warning disable | ||
| // Licensed to the .NET Foundation under one or more agreements. | ||
| // The .NET Foundation licenses this file to you under the MIT license. | ||
|
|
||
| namespace System.Runtime.CompilerServices; | ||
|
|
||
| [AttributeUsage(AttributeTargets.Parameter, AllowMultiple = false, Inherited = false)] | ||
| internal sealed class CallerArgumentExpressionAttribute : Attribute | ||
|
There was a problem hiding this comment. Please consider using PolySharp. It is smart and customizable source generator which will detect what exact feature need to be poly-filled and generate the code for that. There was a problem hiding this comment. Thanks for the suggestion! I’ll definitely take a closer look and see how it can fit into our current approach. There was a problem hiding this comment. @arttonoyan / @wwalendz-relativity, thanks for bringing this to our attention. I need someone else to confirm if bringing an extra library to use these polyfils is okay. @toddbaert or @beeme1mr ? |
||
| { | ||
| public CallerArgumentExpressionAttribute(string parameterName) | ||
| { | ||
| ParameterName = parameterName; | ||
| } | ||
|
|
||
| public string ParameterName { get; } | ||
| } | ||
| #endif | ||
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,14 @@ | ||
| using System.Diagnostics; | ||
| using System.Runtime.CompilerServices; | ||
|
|
||
| namespace OpenFeature; | ||
|
|
||
| [DebuggerStepThrough] | ||
| internal static class Guard | ||
| { | ||
| public static void ThrowIfNull(object? argument, [CallerArgumentExpression(nameof(argument))] string? paramName = null) | ||
| { | ||
| if (argument is null) | ||
| throw new ArgumentNullException(paramName); | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,21 @@ | ||
| // @formatter:off | ||
| // ReSharper disable All | ||
| #if NET5_0_OR_GREATER | ||
| // https://github.com/dotnet/runtime/issues/96197 | ||
| [assembly: System.Runtime.CompilerServices.TypeForwardedTo(typeof(System.Runtime.CompilerServices.IsExternalInit))] | ||
| #else | ||
| #pragma warning disable | ||
| // Licensed to the .NET Foundation under one or more agreements. | ||
| // The .NET Foundation licenses this file to you under the MIT license. | ||
|
|
||
| using System.ComponentModel; | ||
|
|
||
| namespace System.Runtime.CompilerServices; | ||
|
|
||
| /// <summary> | ||
| /// Reserved to be used by the compiler for tracking metadata. | ||
| /// This class should not be used by developers in source code. | ||
| /// </summary> | ||
| [EditorBrowsable(EditorBrowsableState.Never)] | ||
| static class IsExternalInit { } | ||
| #endif |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,31 @@ | ||
| <Project Sdk="Microsoft.NET.Sdk"> | ||
|
|
||
| <PropertyGroup> | ||
| <TargetFrameworks>netstandard2.0;net6.0;net8.0;net462</TargetFrameworks> | ||
| <ImplicitUsings>enable</ImplicitUsings> | ||
| <Nullable>enable</Nullable> | ||
| <RootNamespace>OpenFeature</RootNamespace> | ||
| </PropertyGroup> | ||
|
|
||
| <ItemGroup> | ||
| <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" /> | ||
| </ItemGroup> | ||
|
|
||
| <ItemGroup> | ||
| <ProjectReference Include="..\OpenFeature\OpenFeature.csproj" /> | ||
| </ItemGroup> | ||
|
|
||
| <ItemGroup> | ||
| <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo"> | ||
| <_Parameter1>$(AssemblyName).Tests</_Parameter1> | ||
| </AssemblyAttribute> | ||
| <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo"> | ||
| <_Parameter1>DynamicProxyGenAssembly2</_Parameter1> | ||
| </AssemblyAttribute> | ||
| </ItemGroup> | ||
|
|
||
| <ItemGroup> | ||
| <Folder Include="MultiTarget\" /> | ||
| </ItemGroup> | ||
|
|
||
| </Project> |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,20 @@ | ||
| using Microsoft.Extensions.DependencyInjection; | ||
|
|
||
| namespace OpenFeature; | ||
|
|
||
| /// <summary> | ||
| /// Describes a <see cref="OpenFeatureBuilder"/> backed by an <see cref="IServiceCollection"/>. | ||
| /// </summary> | ||
| /// <param name="services">The services being configured.</param> | ||
| public class OpenFeatureBuilder(IServiceCollection services) | ||
| { | ||
| /// <summary> The services being configured. </summary> | ||
| public IServiceCollection Services { get; } = services; | ||
|
|
||
| /// <summary> | ||
| /// Indicates whether the evaluation context has been configured. | ||
| /// This property is used to determine if specific configurations or services | ||
| /// should be initialized based on the presence of an evaluation context. | ||
| /// </summary> | ||
| public bool IsContextConfigured { get; internal set; } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change | ||||
|---|---|---|---|---|---|---|
| @@ -0,0 +1,65 @@ | ||||||
| using Microsoft.Extensions.DependencyInjection.Extensions; | ||||||
| using OpenFeature.Model; | ||||||
|
|
||||||
| namespace OpenFeature; | ||||||
|
There was a problem hiding this comment.
Suggested change
|
||||||
|
|
||||||
| /// <summary> | ||||||
| /// Contains extension methods for the <see cref="OpenFeatureBuilder"/> class. | ||||||
| /// </summary> | ||||||
| public static partial class OpenFeatureBuilderExtensions | ||||||
| { | ||||||
| /// <summary> | ||||||
| /// This method is used to add a new context to the service collection. | ||||||
| /// </summary> | ||||||
| /// <param name="builder">The <see cref="OpenFeatureBuilder"/> instance.</param> | ||||||
| /// <param name="configure">the desired configuration</param> | ||||||
| /// <returns>The <see cref="OpenFeatureBuilder"/> instance.</returns> | ||||||
| public static OpenFeatureBuilder AddContext( | ||||||
| this OpenFeatureBuilder builder, | ||||||
| Action<EvaluationContextBuilder> configure) | ||||||
| { | ||||||
| Guard.ThrowIfNull(builder); | ||||||
| Guard.ThrowIfNull(configure); | ||||||
|
|
||||||
| return builder.AddContext((b, _) => configure(b)); | ||||||
| } | ||||||
|
|
||||||
| /// <summary> | ||||||
| /// This method is used to add a new context to the service collection. | ||||||
| /// </summary> | ||||||
| /// <param name="builder">The <see cref="OpenFeatureBuilder"/> instance.</param> | ||||||
| /// <param name="configure">the desired configuration</param> | ||||||
| /// <returns>The <see cref="OpenFeatureBuilder"/> instance.</returns> | ||||||
| public static OpenFeatureBuilder AddContext( | ||||||
| this OpenFeatureBuilder builder, | ||||||
| Action<EvaluationContextBuilder, IServiceProvider> configure) | ||||||
| { | ||||||
| Guard.ThrowIfNull(builder); | ||||||
| Guard.ThrowIfNull(configure); | ||||||
|
|
||||||
| builder.IsContextConfigured = true; | ||||||
| builder.Services.TryAddTransient(provider => | ||||||
| { | ||||||
| var contextBuilder = EvaluationContext.Builder(); | ||||||
| configure(contextBuilder, provider); | ||||||
| return contextBuilder.Build(); | ||||||
| }); | ||||||
|
|
||||||
| return builder; | ||||||
| } | ||||||
|
|
||||||
| /// <summary> | ||||||
| /// Adds a feature provider to the service collection. | ||||||
| /// </summary> | ||||||
| /// <typeparam name="T">The type of the feature provider, which must inherit from <see cref="FeatureProvider"/>.</typeparam> | ||||||
| /// <param name="builder">The <see cref="OpenFeatureBuilder"/> instance.</param> | ||||||
| /// <param name="providerFactory">A factory method to create the feature provider, using the service provider.</param> | ||||||
| /// <returns>The <see cref="OpenFeatureBuilder"/> instance.</returns> | ||||||
| public static OpenFeatureBuilder AddProvider<T>(this OpenFeatureBuilder builder, Func<IServiceProvider, T> providerFactory) | ||||||
| where T : FeatureProvider | ||||||
| { | ||||||
| Guard.ThrowIfNull(builder); | ||||||
| builder.Services.TryAddSingleton<FeatureProvider>(providerFactory); | ||||||
| return builder; | ||||||
| } | ||||||
| } | ||||||
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change | ||||
|---|---|---|---|---|---|---|
| @@ -0,0 +1,53 @@ | ||||||
| using Microsoft.Extensions.DependencyInjection; | ||||||
| using Microsoft.Extensions.DependencyInjection.Extensions; | ||||||
| using OpenFeature.Internal; | ||||||
| using OpenFeature.Model; | ||||||
|
|
||||||
| namespace OpenFeature; | ||||||
|
There was a problem hiding this comment.
Suggested change
|
||||||
|
|
||||||
| /// <summary> | ||||||
| /// Contains extension methods for the <see cref="IServiceCollection"/> class. | ||||||
| /// </summary> | ||||||
| public static class OpenFeatureServiceCollectionExtensions | ||||||
| { | ||||||
| /// <summary> | ||||||
| /// This method is used to add OpenFeature to the service collection. | ||||||
| /// OpenFeature will be registered as a singleton. | ||||||
| /// </summary> | ||||||
| /// <param name="services"><see cref="IServiceCollection"/></param> | ||||||
| /// <param name="configure">the desired configuration</param> | ||||||
| /// <returns>the current <see cref="IServiceCollection"/> instance</returns> | ||||||
| public static IServiceCollection AddOpenFeature(this IServiceCollection services, Action<OpenFeatureBuilder> configure) | ||||||
| { | ||||||
| Guard.ThrowIfNull(services); | ||||||
| Guard.ThrowIfNull(configure); | ||||||
|
|
||||||
| services.TryAddSingleton(Api.Instance); | ||||||
| services.TryAddSingleton<IFeatureLifecycleManager, FeatureLifecycleManager>(); | ||||||
|
|
||||||
|
There was a problem hiding this comment. Instead of having branching in all places where we would like to consume There was a problem hiding this comment. We don’t register the EvaluationContext as a singleton because the client can operate without any context or with null. Under the hood, it checks and sets the Empty context as needed. The purpose of IsContextConfigured is to avoid redundant service resolution and nullability checks. If no context is registered, we bypass fetching the EvaluationContext entirely, preventing unnecessary GetService or GetRequiredService calls. Also, when the context is registered, I register it as transient. The reason for this is to control its lifecycle within the scope of the class where it’s used—in this case, IFeatureClient. Will be confusing to register the context as transient in one case and Empty as singleton in another. However, this approach ensures proper lifecycle management based on the context's availability and usage. Additionally, the IsContextConfigured check is only performed once during the service provider building process. In scenarios where context resolution isn’t required, the IFeatureClient can still function without a context, but engineers can always explicitly use ExecutionContext.Empty if needed |
||||||
| var builder = new OpenFeatureBuilder(services); | ||||||
| configure(builder); | ||||||
|
|
||||||
| if (builder.IsContextConfigured) | ||||||
| { | ||||||
| services.TryAddScoped<IFeatureClient>(static provider => | ||||||
| { | ||||||
| var api = provider.GetRequiredService<Api>(); | ||||||
| var client = api.GetClient(); | ||||||
| var context = provider.GetRequiredService<EvaluationContext>(); | ||||||
| client.SetContext(context); | ||||||
|
There was a problem hiding this comment. Context can be added at both the global and client level. Global context is most useful for static values (for example, a value representing the timezone of the server or the cloud provider it's running on, or the application version). We might need multiple contexts setting methods for the different scopes: global, client, and perhaps transaction level once we implement the transaction propagation feature. As it is, I'm not sure it's obvious to a user which one would be used when they do |
||||||
| return client; | ||||||
| }); | ||||||
| } | ||||||
| else | ||||||
| { | ||||||
| services.TryAddScoped<IFeatureClient>(static provider => | ||||||
| { | ||||||
| var api = provider.GetRequiredService<Api>(); | ||||||
| return api.GetClient(); | ||||||
| }); | ||||||
| } | ||||||
|
|
||||||
| return services; | ||||||
| } | ||||||
| } | ||||||
Oops, something went wrong.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Is there any reason for not resolving
FeatureProviderdirectly in the ctor beside having custom exception for that situation? In effect it not allow call-site validation to detect thatFeatureProvideris missing.There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
The main reason for not resolving FeatureProvider directly in the constructor is that some implementations of FeatureProvider are not fully controlled by us, and they may execute significant logic during construction. For example, certain providers like LaunchDarkly perform extensive initialization within the constructor, which can take time and potentially fail (as seen in LaunchDarkly's Provider Implementation and LdClient Constructor).
By not resolving FeatureProvider in the constructor, we can safely perform this logic asynchronously in a start method, which avoids delays or failures during object instantiation. Additionally, I use GetService to log meaningful messages in case of any issues.
In short, this approach allows us to handle potential failures asynchronously during startup and ensures proper logging in case of errors.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Ideally providers are doing such initialization in their
initialize()method, but we can't control them all, and I see your point. Generally I'd prefer constructor resolution as well but I can understand the advantages you describe.