Add version to test tool

.autover/changes/efa829ed-59af-46eb-a5e5-ef471698c82d.json

@@ -0,0 +1,11 @@
+{
+  "Projects": [
+    {
+      "Name": "Amazon.Lambda.TestTool",
+      "Type": "Patch",
+      "ChangelogMessages": [
+        "Add --version switch to allow integrators to check what version is installed"
+      ]
+    }
+  ]
+}

Tools/LambdaTestTool-v2/src/Amazon.Lambda.TestTool/Commands/RunCommand.cs

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0
 
 using System.Diagnostics;
+using System.Text.Json;
 using Amazon.Lambda.TestTool.Commands.Settings;
 using Amazon.Lambda.TestTool.Extensions;
 using Amazon.Lambda.TestTool.Models;
@@ -28,6 +29,12 @@ public override async Task<int> ExecuteAsync(CommandContext context, RunCommandS
     {
         try
         {
+            if (settings.PrintToolInfo)
+            {
+                PrintToolInfo();
+                return CommandReturnCodes.Success;
+            }
+
             EvaluateEnvironmentVariables(settings);
 
             if (!settings.LambdaEmulatorPort.HasValue && !settings.ApiGatewayEmulatorPort.HasValue)
@@ -101,6 +108,11 @@ public override async Task<int> ExecuteAsync(CommandContext context, RunCommandS
         }
     }
 
+    private void PrintToolInfo()
+    {
+        toolInteractiveService.WriteLine(Utilities.Utils.GenerateToolInfoJson());
+    }
+
     private void EvaluateEnvironmentVariables(RunCommandSettings settings)
     {
         var environmentVariables = environmentManager.GetEnvironmentVariables();

Tools/LambdaTestTool-v2/src/Amazon.Lambda.TestTool/Commands/Settings/RunCommandSettings.cs

@@ -69,4 +69,11 @@ public sealed class RunCommandSettings : CommandSettings
     [CommandOption("--api-gateway-emulator-port <PORT>")]
     [Description("The port number used for the test tool's API Gateway emulator.")]
     public int? ApiGatewayEmulatorPort { get; set; }
+
+    /// <summary>
+    /// When set the tool prints metadata for the including the version number as a JSON document and then exits.
+    /// </summary>
+    [CommandOption("--tool-info")]
+    [Description("When set the tool prints metadata for the including the version number as a JSON document and then exits.")]
+    public bool PrintToolInfo { get; set; }
 }

Tools/LambdaTestTool-v2/src/Amazon.Lambda.TestTool/Utilities/Utils.cs

@@ -21,7 +21,7 @@ public static string DetermineToolVersion()
         AssemblyInformationalVersionAttribute? attribute = null;
         try
         {
-            var assembly = Assembly.GetEntryAssembly();
+            var assembly = typeof(Utils).Assembly;
             if (assembly == null)
                 return unknownVersion;
             attribute = assembly.GetCustomAttribute<AssemblyInformationalVersionAttribute>();
@@ -42,6 +42,23 @@ public static string DetermineToolVersion()
         return version ?? unknownVersion;
     }
 
+    public static string GenerateToolInfoJson()
+    {
+        var stream = new MemoryStream();
+        Utf8JsonWriter utf8JsonWriter = new Utf8JsonWriter(stream, options: new JsonWriterOptions()
+        {
+            Indented = false
+        });
+        utf8JsonWriter.WriteStartObject();
+        utf8JsonWriter.WriteString("version", Utilities.Utils.DetermineToolVersion());
+        utf8JsonWriter.WriteString("install-path", Directory.GetParent(typeof(Utils).Assembly.Location)!.FullName);
+        utf8JsonWriter.WriteEndObject();
+        utf8JsonWriter.Flush();
+
+        stream.Position = 0;
+        return new StreamReader(stream).ReadToEnd();
+    }
+
     /// <summary>
     /// If true it means the test tool was launched via an Aspire AppHost.
     /// </summary>

Tools/LambdaTestTool-v2/tests/Amazon.Lambda.TestTool.UnitTests/Commands/RunCommandTests.cs

@@ -11,6 +11,7 @@
 using Xunit;
 using Amazon.Lambda.TestTool.Services.IO;
 using Amazon.Lambda.TestTool.Utilities;
+using System.Text.Json.Nodes;
 
 namespace Amazon.Lambda.TestTool.UnitTests.Commands;
 
@@ -100,4 +101,42 @@ public async Task ExecuteAsync_EnvPorts_SuccessfulLaunch()
         Assert.Equal(CommandReturnCodes.Success, result);
         Assert.True(isApiRunning);
     }
+
+    [Fact]
+    public async Task VerifyToolInfo()
+    {
+        var writeCalls = 0;
+        string? versionInfo = null;
+        Mock<IToolInteractiveService> mockInteractiveService = new Mock<IToolInteractiveService>();
+        mockInteractiveService.Setup(i => i.WriteLine(It.IsAny<string>()))
+            .Callback((string message) =>
+            {
+                writeCalls++;
+                versionInfo = message;
+            });
+
+        var cancellationSource = new CancellationTokenSource();
+        var settings = new RunCommandSettings { PrintToolInfo = true };
+        var command = new RunCommand(mockInteractiveService.Object, _mockEnvironmentManager.Object);
+        var context = new CommandContext(new List<string>(), _mockRemainingArgs.Object, "run", null);
+        await command.ExecuteAsync(context, settings, cancellationSource);
+
+        Assert.Equal(1, writeCalls);
+        Assert.True(!string.IsNullOrEmpty(versionInfo));
+
+        JsonNode? jsonNode = JsonNode.Parse(versionInfo);
+        Assert.NotNull(jsonNode);
+
+        var version = jsonNode["version"]?.ToString();
+        Assert.NotNull(version);
+
+        // The Version.TryParse does not like the preview suffix
+        version = version.Replace("-preview", "");
+        Assert.True(Version.TryParse(version, out var _));
+
+        var installPath = jsonNode["install-path"]?.ToString();
+        Assert.NotNull(installPath);
+        Assert.True(Directory.Exists(installPath));
+        Assert.True(Path.IsPathFullyQualified(installPath));
+    }
 }