feat(tests): add unit tests for ConsoleWrapper and Metrics middleware extensions

Author: hjgraca

libraries/tests/AWS.Lambda.Powertools.Common.Tests/ConsoleWrapperTests.cs

@@ -0,0 +1,53 @@
+using System;
+using System.IO;
+using Xunit;
+
+namespace AWS.Lambda.Powertools.Common.Tests;
+
+public class ConsoleWrapperTests
+{
+    [Fact]
+    public void WriteLine_Should_Write_To_Console()
+    {
+        // Arrange
+        var consoleWrapper = new ConsoleWrapper();
+        var writer = new StringWriter();
+        Console.SetOut(writer);
+
+        // Act
+        consoleWrapper.WriteLine("test message");
+
+        // Assert
+        Assert.Equal($"test message{Environment.NewLine}", writer.ToString());
+    }
+
+    [Fact]
+    public void Error_Should_Write_To_Error_Console()
+    {
+        // Arrange
+        var consoleWrapper = new ConsoleWrapper();
+        var writer = new StringWriter();
+        Console.SetError(writer);
+
+        // Act
+        consoleWrapper.Error("error message");
+
+        // Assert
+        Assert.Equal($"error message{Environment.NewLine}", writer.ToString());
+    }
+
+    [Fact]
+    public void ReadLine_Should_Read_From_Console()
+    {
+        // Arrange
+        var consoleWrapper = new ConsoleWrapper();
+        var reader = new StringReader("input text");
+        Console.SetIn(reader);
+
+        // Act
+        var result = consoleWrapper.ReadLine();
+
+        // Assert
+        Assert.Equal("input text", result);
+    }
+}

libraries/tests/AWS.Lambda.Powertools.Metrics.AspNetCore.Tests/MetricsMiddlewareExtensionsTests.cs

@@ -0,0 +1,104 @@
+using Amazon.Lambda.TestUtilities;
+using AWS.Lambda.Powertools.Common;
+using AWS.Lambda.Powertools.Metrics.AspNetCore.Http;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.TestHost;
+using Microsoft.Extensions.DependencyInjection;
+using NSubstitute;
+using Xunit;
+
+namespace AWS.Lambda.Powertools.Metrics.AspNetCore.Tests;
+
+public class MetricsMiddlewareExtensionsTests : IDisposable
+{
+    [Fact]
+    public async Task When_UseMetrics_Should_Add_ColdStart()
+    {
+        // Arrange
+        var options = new MetricsOptions
+        {
+            CaptureColdStart = true,
+            Namespace = "TestNamespace",
+            Service = "TestService"
+        };
+        
+        var conf = Substitute.For<IPowertoolsConfigurations>();
+        var consoleWrapper = Substitute.For<IConsoleWrapper>();
+        var metrics = new Metrics(conf, consoleWrapper: consoleWrapper, options: options);
+
+        var builder = WebApplication.CreateBuilder();
+        builder.Services.AddSingleton<IMetrics>(metrics);
+        builder.WebHost.UseTestServer();
+
+        var app = builder.Build();
+        app.UseMetrics();
+        app.MapGet("/test", () => Results.Ok());
+
+        await app.StartAsync();
+        var client = app.GetTestClient();
+
+        // Act
+        var response = await client.GetAsync("/test");
+
+        // Assert
+        Assert.Equal(200, (int)response.StatusCode);
+        consoleWrapper.Received(1).WriteLine(
+            Arg.Is<string>(s => s.Contains("CloudWatchMetrics\":[{\"Namespace\":\"TestNamespace\",\"Metrics\":[{\"Name\":\"ColdStart\",\"Unit\":\"Count\"}],\"Dimensions\":[[]]}]},\"ColdStart\":1}"))
+        );
+
+        await app.StopAsync();
+    }
+
+    [Fact]
+    public async Task When_UseMetrics_Should_Add_ColdStart_With_LambdaContext()
+    {
+        // Arrange
+        var options = new MetricsOptions
+        {
+            CaptureColdStart = true,
+            Namespace = "TestNamespace",
+            Service = "TestService"
+        };
+        
+        var conf = Substitute.For<IPowertoolsConfigurations>();
+        var consoleWrapper = Substitute.For<IConsoleWrapper>();
+        var metrics = new Metrics(conf, consoleWrapper: consoleWrapper, options: options);
+
+        var builder = WebApplication.CreateBuilder();
+        builder.Services.AddSingleton<IMetrics>(metrics);
+        builder.WebHost.UseTestServer();
+
+        var app = builder.Build();
+        app.Use(async (context, next) =>
+        {
+            var lambdaContext = new TestLambdaContext
+            {
+                FunctionName = "TestFunction"
+            };
+            context.Items["LambdaContext"] = lambdaContext;
+            await next();
+        });
+        app.UseMetrics();
+        app.MapGet("/test", () => Results.Ok());
+
+        await app.StartAsync();
+        var client = app.GetTestClient();
+
+        // Act
+        var response = await client.GetAsync("/test");
+
+        // Assert
+        Assert.Equal(200, (int)response.StatusCode);
+        consoleWrapper.Received(1).WriteLine(
+            Arg.Is<string>(s => s.Contains("CloudWatchMetrics\":[{\"Namespace\":\"TestNamespace\",\"Metrics\":[{\"Name\":\"ColdStart\",\"Unit\":\"Count\"}],\"Dimensions\":[[\"FunctionName\"]]}]},\"FunctionName\":\"TestFunction\",\"ColdStart\":1}"))
+        );
+
+        await app.StopAsync();
+    }
+
+    public void Dispose()
+    {
+        MetricsHelper.ResetColdStart();
+    }
+}