EvaluationEventBuilderTests.cs

using System.Collections.Generic;
using OpenFeature.Constant;
using OpenFeature.Model;
using OpenFeature.Telemetry;
using Xunit;

namespace OpenFeature.Tests.Telemetry
{
    public class EvaluationEventBuilderTests
    {
        [Fact]
        public void Build_ShouldReturnEventWithCorrectAttributes()
        {
            // Arrange
            var clientMetadata = new ClientMetadata("client", "1.0.0");
            var providerMetadata = new Metadata("provider");
            var hookContext = new HookContext<Value>("flagKey", new Value(), FlagValueType.Object, clientMetadata,
                providerMetadata, EvaluationContext.Empty);
            var metadata = new Dictionary<string, object>
            {
                { "flagSetId", "flagSetId" }, { "contextId", "contextId" }, { "version", "version" }
            };
            var flagMetadata = new ImmutableMetadata(metadata);
            var details = new FlagEvaluationDetails<Value>("flagKey", new Value("value"), ErrorType.None,
                reason: "reason", variant: "variant", flagMetadata: flagMetadata);

            // Act
            var evaluationEvent = EvaluationEventBuilder.Build(hookContext, details);

            // Assert
            Assert.Equal("feature_flag.evaluation", evaluationEvent.Name);
            Assert.Equal("flagKey", evaluationEvent.Attributes[TelemetryConstants.Key]);
            Assert.Equal("provider", evaluationEvent.Attributes[TelemetryConstants.Provider]);
            Assert.Equal("reason", evaluationEvent.Attributes[TelemetryConstants.Reason]);
            Assert.Equal("variant", evaluationEvent.Attributes[TelemetryConstants.Variant]);
            Assert.Equal("contextId", evaluationEvent.Attributes[TelemetryFlagMetadata.ContextId]);
            Assert.Equal("flagSetId", evaluationEvent.Attributes[TelemetryFlagMetadata.FlagSetId]);
            Assert.Equal("version", evaluationEvent.Attributes[TelemetryFlagMetadata.Version]);
        }

        [Fact]
        public void Build_ShouldHandleErrorDetails()
        {
            // Arrange
            var clientMetadata = new ClientMetadata("client", "1.0.0");
            var providerMetadata = new Metadata("provider");
            var hookContext = new HookContext<Value>("flagKey", new Value(), FlagValueType.Object, clientMetadata,
                providerMetadata, EvaluationContext.Empty);
            var metadata = new Dictionary<string, object>
            {
                { "flagSetId", "flagSetId" }, { "contextId", "contextId" }, { "version", "version" }
            };
            var flagMetadata = new ImmutableMetadata(metadata);
            var details = new FlagEvaluationDetails<Value>("flagKey", new Value("value"), ErrorType.General,
                errorMessage: "errorMessage", reason: "reason", variant: "variant", flagMetadata: flagMetadata);

            // Act
            var evaluationEvent = EvaluationEventBuilder.Build(hookContext, details);

            // Assert
            Assert.Equal("general", evaluationEvent.Attributes[TelemetryConstants.ErrorCode]);
            Assert.Equal("errorMessage", evaluationEvent.Attributes[TelemetryConstants.ErrorMessage]);
        }

        [Fact]
        public void Build_ShouldHandleMissingVariant()
        {
            // Arrange
            var clientMetadata = new ClientMetadata("client", "1.0.0");
            var providerMetadata = new Metadata("provider");
            var hookContext = new HookContext<Value>("flagKey", new Value("value"), FlagValueType.Object, clientMetadata,
                providerMetadata, EvaluationContext.Empty);
            var metadata = new Dictionary<string, object>
            {
                { "flagSetId", "flagSetId" }, { "contextId", "contextId" }, { "version", "version" }
            };
            var flagMetadata = new ImmutableMetadata(metadata);
            var details = new FlagEvaluationDetails<Value>("flagKey", new Value("value"), ErrorType.None,
                reason: "reason", variant: null, flagMetadata: flagMetadata);

            // Act
            var evaluationEvent = EvaluationEventBuilder.Build(hookContext, details);

            // Assert
            Assert.Null(evaluationEvent.Attributes[TelemetryConstants.Variant]);
        }

        [Fact]
        public void Build_ShouldHandleMissingFlagMetadata()
        {
            // Arrange
            var clientMetadata = new ClientMetadata("client", "1.0.0");
            var providerMetadata = new Metadata("provider");
            var hookContext = new HookContext<Value>("flagKey", new Value("value"), FlagValueType.Object, clientMetadata,
                providerMetadata, EvaluationContext.Empty);
            var flagMetadata = new ImmutableMetadata();
            var details = new FlagEvaluationDetails<Value>("flagKey", new Value("value"), ErrorType.None,
                reason: "reason", variant: "", flagMetadata: flagMetadata);

            // Act
            var evaluationEvent = EvaluationEventBuilder.Build(hookContext, details);

            // Assert
            Assert.Null(evaluationEvent.Attributes[TelemetryFlagMetadata.ContextId]);
            Assert.Null(evaluationEvent.Attributes[TelemetryFlagMetadata.FlagSetId]);
            Assert.Null(evaluationEvent.Attributes[TelemetryFlagMetadata.Version]);
        }

        [Theory]
        [InlineData(null)]
        [InlineData("")]
        [InlineData(" ")]
        public void Build_ShouldHandleMissingReason(string? reason)
        {
            // Arrange
            var clientMetadata = new ClientMetadata("client", "1.0.0");
            var providerMetadata = new Metadata("provider");
            var hookContext = new HookContext<Value>("flagKey", new Value("value"), FlagValueType.Object, clientMetadata,
                providerMetadata, EvaluationContext.Empty);
            var flagMetadata = new ImmutableMetadata();
            var details = new FlagEvaluationDetails<Value>("flagKey", new Value("value"), ErrorType.None,
                reason: reason, variant: "", flagMetadata: flagMetadata);

            // Act
            var evaluationEvent = EvaluationEventBuilder.Build(hookContext, details);

            // Assert
            Assert.Equal(Reason.Unknown, evaluationEvent.Attributes[TelemetryConstants.Reason]);
        }
    }
}