Add aspire test command with pytest support and auxiliary backchannel infrastructure

playground/python/Python.AppHost/Program.cs

@@ -3,22 +3,22 @@
 
 var builder = DistributedApplication.CreateBuilder(args);
 
-builder.AddPythonApp("script-only", "../script_only", "main.py");
+builder.AddPythonApp("scriptonly", "../script_only", "main.py");
 builder.AddPythonApp("instrumented-script", "../instrumented_script", "main.py");
 
-builder.AddPythonModule("fastapi-app", "../module_only", "uvicorn")
+builder.AddPythonModule("fastapiapp", "../module_only", "uvicorn")
     .WithArgs("api:app", "--reload", "--host=0.0.0.0", "--port=8000")
     .WithHttpEndpoint(targetPort: 8000)
     .WithUv();
 
 // Run the same app on another port using uvicorn directly
-builder.AddPythonExecutable("fastapi-uvicorn-app", "../module_only", "uvicorn")
+builder.AddPythonExecutable("fastapiuvicornapp", "../module_only", "uvicorn")
     .WithDebugging()
     .WithArgs("api:app", "--reload", "--host=0.0.0.0", "--port=8001")
     .WithHttpEndpoint(targetPort: 8001);
 
 // Flask app using Flask module directly
-builder.AddPythonModule("flask-app", "../flask_app", "flask")
+builder.AddPythonModule("flaskapp", "../flask_app", "flask")
     .WithEnvironment("FLASK_APP", "app:create_app")
     .WithArgs(c =>
     {
@@ -30,10 +30,14 @@
     .WithUv();
 
 // Uvicorn app using the AddUvicornApp method
-builder.AddUvicornApp("uvicorn-app", "../uvicorn_app", "app:app")
+var uvicornApp = builder.AddUvicornApp("uvicornapp", "../uvicorn_app", "app:app")
     .WithUv()
     .WithExternalHttpEndpoints();
 
+builder.AddPytest("uvicorn-tests", "../uvicorn_app")
+    .WithReference(uvicornApp).WaitFor(uvicornApp)
+    .WithUv();
+
 #if !SKIP_DASHBOARD_REFERENCE
 // This project is only added in playground projects to support development/debugging
 // of the dashboard. It is not required in end developer code. Comment out this code

playground/python/uvicorn_app/app.py

@@ -27,6 +27,7 @@ async def root():
         """Root endpoint."""
         return "API service is running. Navigate to /weatherforecast to see sample data."
 
+@app.get("/weatherforecast")
 async def weather_forecast():
     """Weather forecast endpoint."""
     # Generate fresh data if not in cache or cache unavailable.

playground/python/uvicorn_app/pyproject.toml

@@ -9,3 +9,9 @@ dependencies = [
     "opentelemetry-exporter-otlp-proto-grpc>=1.38.0",
     "opentelemetry-instrumentation-fastapi>=0.59b0",
 ]
+
+[dependency-groups]
+dev = [
+    "pytest>=8.0.0",
+    "httpx>=0.27.0",
+]

playground/python/uvicorn_app/tests/__init__.py

@@ -0,0 +1,2 @@
+# Licensed to the .NET Foundation under one or more agreements.
+# The .NET Foundation licenses this file to you under the MIT license.

playground/python/uvicorn_app/tests/test_restapi.py

@@ -0,0 +1,46 @@
+# Licensed to the .NET Foundation under one or more agreements.
+# The .NET Foundation licenses this file to you under the MIT license.
+
+"""Integration tests for the uvicorn app endpoints."""
+
+import os
+
+import httpx
+import pytest
+
+
+@pytest.fixture
+def base_url():
+    """Get the base URL from environment variable."""
+    url = os.environ.get("UVICORNAPP_HTTP")
+    if not url:
+        pytest.skip("UVICORNAPP_HTTP environment variable not set")
+    return url.rstrip("/")
+
+
+def test_root_endpoint(base_url):
+    """Test the root endpoint returns expected message."""
+    response = httpx.get(f"{base_url}/")
+    assert response.status_code == 200
+    assert "API service is running" in response.text
+
+
+def test_weatherforecast_endpoint(base_url):
+    """Test the weatherforecast endpoint returns valid forecast data."""
+    response = httpx.get(f"{base_url}/weatherforecast")
+    assert response.status_code == 200
+    data = response.json()
+    assert isinstance(data, list)
+    assert len(data) == 5
+    for item in data:
+        assert "date" in item
+        assert "temperatureC" in item
+        assert "temperatureF" in item
+        assert "summary" in item
+
+
+def test_health_endpoint(base_url):
+    """Test the health check endpoint returns healthy status."""
+    response = httpx.get(f"{base_url}/health")
+    assert response.status_code == 200
+    assert response.text == "Healthy"

src/Aspire.Cli/Backchannel/AuxiliaryBackchannel.cs

@@ -0,0 +1,47 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using StreamJsonRpc;
+
+namespace Aspire.Cli.Backchannel;
+
+/// <summary>
+/// Encapsulates communication with an AppHost via the auxiliary backchannel.
+/// </summary>
+internal sealed class AuxiliaryBackchannel : IAuxiliaryBackchannel
+{
+    private readonly JsonRpc _rpc;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="AuxiliaryBackchannel"/> class.
+    /// </summary>
+    /// <param name="rpc">The JSON-RPC connection to the AppHost.</param>
+    public AuxiliaryBackchannel(JsonRpc rpc)
+    {
+        _rpc = rpc ?? throw new ArgumentNullException(nameof(rpc));
+    }
+
+    /// <inheritdoc/>
+    public Task<AppHostInformation?> GetAppHostInformationAsync(CancellationToken cancellationToken = default)
+    {
+        return _rpc.InvokeWithCancellationAsync<AppHostInformation?>("GetAppHostInformationAsync", cancellationToken: cancellationToken);
+    }
+
+    /// <inheritdoc/>
+    public Task<DashboardMcpConnectionInfo?> GetDashboardMcpConnectionInfoAsync(CancellationToken cancellationToken = default)
+    {
+        return _rpc.InvokeWithCancellationAsync<DashboardMcpConnectionInfo?>("GetDashboardMcpConnectionInfoAsync", cancellationToken: cancellationToken);
+    }
+
+    /// <inheritdoc/>
+    public Task<TestResults?> GetTestResultsAsync(CancellationToken cancellationToken = default)
+    {
+        return _rpc.InvokeWithCancellationAsync<TestResults?>("GetTestResultsAsync", cancellationToken: cancellationToken);
+    }
+
+    /// <inheritdoc/>
+    public Task StopAppHostAsync(CancellationToken cancellationToken = default)
+    {
+        return _rpc.InvokeWithCancellationAsync("StopAppHostAsync", cancellationToken: cancellationToken);
+    }
+}

src/Aspire.Cli/Backchannel/AuxiliaryBackchannelMonitor.cs

@@ -185,16 +185,19 @@ private async Task TryConnectToSocketAsync(string socketPath, CancellationToken
             var rpc = new JsonRpc(new HeaderDelimitedMessageHandler(stream, stream, BackchannelJsonSerializerContext.CreateRpcMessageFormatter()));
             rpc.StartListening();
 
+            // Create the auxiliary backchannel wrapper
+            var backchannel = new AuxiliaryBackchannel(rpc);
+
             // Get the AppHost information
-            var appHostInfo = await rpc.InvokeAsync<AppHostInformation?>("GetAppHostInformationAsync").ConfigureAwait(false);
+            var appHostInfo = await backchannel.GetAppHostInformationAsync(cancellationToken).ConfigureAwait(false);
 
             // Get the MCP connection info
-            var mcpInfo = await rpc.InvokeAsync<DashboardMcpConnectionInfo?>("GetDashboardMcpConnectionInfoAsync").ConfigureAwait(false);
+            var mcpInfo = await backchannel.GetDashboardMcpConnectionInfoAsync(cancellationToken).ConfigureAwait(false);
 
             // Determine if this AppHost is in scope of the MCP server's working directory
             var isInScope = IsAppHostInScope(appHostInfo?.AppHostPath);
 
-            var connection = new AppHostConnection(hash, socketPath, rpc, mcpInfo, appHostInfo, isInScope);
+            var connection = new AppHostConnection(hash, socketPath, rpc, backchannel, mcpInfo, appHostInfo, isInScope);
 
             // Set up disconnect handler
             rpc.Disconnected += (sender, args) =>
@@ -320,11 +323,12 @@ internal sealed class AppHostConnection
     /// <summary>
     /// Initializes a new instance of the <see cref="AppHostConnection"/> class.
     /// </summary>
-    public AppHostConnection(string hash, string socketPath, JsonRpc rpc, DashboardMcpConnectionInfo? mcpInfo, AppHostInformation? appHostInfo, bool isInScope)
+    public AppHostConnection(string hash, string socketPath, JsonRpc rpc, IAuxiliaryBackchannel backchannel, DashboardMcpConnectionInfo? mcpInfo, AppHostInformation? appHostInfo, bool isInScope)
     {
         Hash = hash;
         SocketPath = socketPath;
         Rpc = rpc;
+        Backchannel = backchannel;
         McpInfo = mcpInfo;
         AppHostInfo = appHostInfo;
         IsInScope = isInScope;
@@ -346,6 +350,11 @@ public AppHostConnection(string hash, string socketPath, JsonRpc rpc, DashboardM
     /// </summary>
     public JsonRpc Rpc { get; }
 
+    /// <summary>
+    /// Gets the auxiliary backchannel for communicating with the AppHost.
+    /// </summary>
+    public IAuxiliaryBackchannel Backchannel { get; }
+
     /// <summary>
     /// Gets the MCP connection information for the Dashboard.
     /// </summary>

src/Aspire.Cli/Backchannel/BackchannelJsonSerializerContext.cs

@@ -35,6 +35,9 @@ namespace Aspire.Cli.Backchannel;
 [JsonSerializable(typeof(AppHostProjectSearchResultPoco))]
 [JsonSerializable(typeof(DashboardMcpConnectionInfo))]
 [JsonSerializable(typeof(AppHostInformation))]
+[JsonSerializable(typeof(TestResults))]
+[JsonSerializable(typeof(TestResourceResult))]
+[JsonSerializable(typeof(TestResultFileInfo))]
 internal partial class BackchannelJsonSerializerContext : JsonSerializerContext
 {
     [UnconditionalSuppressMessage("ReflectionAnalysis", "IL2026:RequiresUnreferencedCode", Justification = "Using the Json source generator.")]

src/Aspire.Cli/Backchannel/IAuxiliaryBackchannel.cs

@@ -0,0 +1,38 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Aspire.Cli.Backchannel;
+
+/// <summary>
+/// Interface for communicating with an AppHost via the auxiliary backchannel.
+/// </summary>
+internal interface IAuxiliaryBackchannel
+{
+    /// <summary>
+    /// Gets information about the AppHost.
+    /// </summary>
+    /// <param name="cancellationToken">A cancellation token.</param>
+    /// <returns>The AppHost information including the fully qualified path and process ID.</returns>
+    Task<AppHostInformation?> GetAppHostInformationAsync(CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Gets the Dashboard MCP connection information including endpoint URL and API token.
+    /// </summary>
+    /// <param name="cancellationToken">A cancellation token.</param>
+    /// <returns>The MCP connection information, or null if the dashboard is not part of the application model.</returns>
+    Task<DashboardMcpConnectionInfo?> GetDashboardMcpConnectionInfoAsync(CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Gets the test results by waiting for all test resources to complete.
+    /// </summary>
+    /// <param name="cancellationToken">A cancellation token.</param>
+    /// <returns>The test results.</returns>
+    Task<TestResults?> GetTestResultsAsync(CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Initiates an orderly shutdown of the AppHost.
+    /// </summary>
+    /// <param name="cancellationToken">A cancellation token.</param>
+    /// <returns>A task that completes when the shutdown request has been sent.</returns>
+    Task StopAppHostAsync(CancellationToken cancellationToken = default);
+}

src/Aspire.Cli/Commands/RootCommand.cs

@@ -32,6 +32,7 @@ public RootCommand(
         ExecCommand execCommand,
         UpdateCommand updateCommand,
         McpCommand mcpCommand,
+        TestCommand testCommand,
         ExtensionInternalCommand extensionInternalCommand,
         IFeatures featureFlags,
         IInteractionService interactionService)
@@ -49,6 +50,7 @@ public RootCommand(
         ArgumentNullException.ThrowIfNull(updateCommand);
         ArgumentNullException.ThrowIfNull(execCommand);
         ArgumentNullException.ThrowIfNull(mcpCommand);
+        ArgumentNullException.ThrowIfNull(testCommand);
         ArgumentNullException.ThrowIfNull(extensionInternalCommand);
         ArgumentNullException.ThrowIfNull(featureFlags);
         ArgumentNullException.ThrowIfNull(interactionService);
@@ -122,5 +124,10 @@ public RootCommand(
             Subcommands.Add(execCommand);
         }
 
+        if (featureFlags.IsFeatureEnabled(KnownFeatures.TestCommandEnabled, false))
+        {
+            Subcommands.Add(testCommand);
+        }
+
     }
 }