Adding the ability to do a maven build in the app host

This uses an event to run the mvnw build (or it can be customised via options), so it is only used when the app host is running the resource

Fixes #339

examples/java/CommunityToolkit.Aspire.Hosting.Java.AppHost/CommunityToolkit.Aspire.Hosting.Java.AppHost.csproj

@@ -20,9 +20,4 @@
     <ProjectReference Include="..\..\..\src\CommunityToolkit.Aspire.Hosting.Java\CommunityToolkit.Aspire.Hosting.Java.csproj" IsAspireProjectResource="false" />
   </ItemGroup>
 
-  <Target Name="PublishRunMaven" AfterTargets="Build">
-    <!-- As part of publishing, ensure the Java app is freshly built -->
-    <Exec WorkingDirectory="$(JavaAppRoot)" Command="./mvnw --quiet clean package" />
-  </Target>
-
 </Project>

examples/java/CommunityToolkit.Aspire.Hosting.Java.AppHost/Program.cs

@@ -16,6 +16,7 @@
                                Port = 8085,
                                OtelAgentPath = "../../../agents",
                            })
+                           .WithMavenBuild()
                            .PublishAsDockerFile(
                            [
                                new DockerBuildArg("JAR_NAME", "spring-maven-0.0.1-SNAPSHOT.jar"),

src/CommunityToolkit.Aspire.Hosting.Java/JavaAppHostingExtension.Container.cs

@@ -0,0 +1,56 @@
+using System.Globalization;
+using Aspire.Hosting.ApplicationModel;
+using CommunityToolkit.Aspire.Utils;
+
+namespace Aspire.Hosting;
+
+/// <summary>
+/// Provides extension methods for adding Java applications to an <see cref="IDistributedApplicationBuilder"/>.
+/// </summary>
+public static partial class JavaAppHostingExtension
+{
+    /// <summary>
+    /// Adds a Java application to the application model. Executes the containerized Java app.
+    /// </summary>
+    /// <param name="builder">The <see cref="IDistributedApplicationBuilder"/> to add the resource to.</param>
+    /// <param name="name">The name of the resource.</param>
+    /// <param name="options">The <see cref="JavaAppContainerResourceOptions"/> to configure the Java application.</param>"
+    /// <returns>A reference to the <see cref="IResourceBuilder{T}"/>.</returns>
+    public static IResourceBuilder<JavaAppContainerResource> AddJavaApp(this IDistributedApplicationBuilder builder, [ResourceName] string name, JavaAppContainerResourceOptions options)
+    {
+        ArgumentNullException.ThrowIfNull(builder, nameof(builder));
+        ArgumentNullException.ThrowIfNull(options, nameof(options));
+        ArgumentException.ThrowIfNullOrWhiteSpace(name, nameof(name));
+        ArgumentException.ThrowIfNullOrWhiteSpace(options.ContainerImageName, nameof(options.ContainerImageName));
+
+        var resource = new JavaAppContainerResource(name);
+
+        var rb = builder.AddResource(resource)
+          .WithAnnotation(new ContainerImageAnnotation { Image = options.ContainerImageName, Tag = options.ContainerImageTag, Registry = options.ContainerRegistry })
+          .WithHttpEndpoint(port: options.Port, targetPort: options.TargetPort, name: JavaAppContainerResource.HttpEndpointName)
+          .WithJavaDefaults(options);
+
+        if (options.Args is { Length: > 0 })
+        {
+            rb.WithArgs(options.Args);
+        }
+
+        return rb;
+    }
+
+    /// <summary>
+    /// Adds a Spring application to the application model. Executes the containerized Spring app.
+    /// </summary>
+    /// <param name="builder">The <see cref="IDistributedApplicationBuilder"/> to add the resource to.</param>
+    /// <param name="name">The name of the resource.</param>
+    /// <param name="options">The <see cref="JavaAppContainerResourceOptions"/> to configure the Java application.</param>"
+    /// <returns>A reference to the <see cref="IResourceBuilder{T}"/>.</returns>
+    public static IResourceBuilder<JavaAppContainerResource> AddSpringApp(this IDistributedApplicationBuilder builder, [ResourceName] string name, JavaAppContainerResourceOptions options) =>
+        builder.AddJavaApp(name, options);
+
+    private static IResourceBuilder<JavaAppContainerResource> WithJavaDefaults(
+        this IResourceBuilder<JavaAppContainerResource> builder,
+        JavaAppContainerResourceOptions options) =>
+        builder.WithOtlpExporter()
+               .WithEnvironment("JAVA_TOOL_OPTIONS", $"-javaagent:{options.OtelAgentPath?.TrimEnd('/')}/opentelemetry-javaagent.jar");
+}

src/CommunityToolkit.Aspire.Hosting.Java/JavaAppHostingExtension.Executable.cs

@@ -0,0 +1,160 @@
+using System.Diagnostics;
+using System.Globalization;
+using System.Runtime.InteropServices;
+using Aspire.Hosting.ApplicationModel;
+using CommunityToolkit.Aspire.Utils;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
+
+namespace Aspire.Hosting;
+
+/// <summary>
+/// Provides extension methods for adding Java applications to an <see cref="IDistributedApplicationBuilder"/>.
+/// </summary>
+public static partial class JavaAppHostingExtension
+{
+    /// <summary>
+    /// Adds a Java application to the application model. Executes the executable Java app.
+    /// </summary>
+    /// <param name="builder">The <see cref="IDistributedApplicationBuilder"/> to add the resource to.</param>
+    /// <param name="name">The name of the resource.</param>
+    /// <param name="workingDirectory">The working directory to use for the command. If null, the working directory of the current process is used.</param>
+    /// <param name="options">The <see cref="JavaAppExecutableResourceOptions"/> to configure the Java application.</param>"
+    /// <returns>A reference to the <see cref="IResourceBuilder{T}"/>.</returns>
+    public static IResourceBuilder<JavaAppExecutableResource> AddJavaApp(this IDistributedApplicationBuilder builder, [ResourceName] string name, string workingDirectory, JavaAppExecutableResourceOptions options)
+    {
+        ArgumentNullException.ThrowIfNull(builder, nameof(builder));
+        ArgumentNullException.ThrowIfNull(options, nameof(options));
+        ArgumentException.ThrowIfNullOrWhiteSpace(name, nameof(name));
+        ArgumentException.ThrowIfNullOrWhiteSpace(workingDirectory, nameof(workingDirectory));
+
+#pragma warning disable CS8601 // Possible null reference assignment.
+        string[] allArgs = options.Args is { Length: > 0 }
+            ? ["-jar", options.ApplicationName, .. options.Args]
+            : ["-jar", options.ApplicationName];
+#pragma warning restore CS8601 // Possible null reference assignment.
+
+        workingDirectory = PathNormalizer.NormalizePathForCurrentPlatform(Path.Combine(builder.AppHostDirectory, workingDirectory));
+        var resource = new JavaAppExecutableResource(name, "java", workingDirectory);
+
+        return builder.AddResource(resource)
+                      .WithJavaDefaults(options)
+                      .WithHttpEndpoint(port: options.Port, name: JavaAppContainerResource.HttpEndpointName, isProxied: false)
+                      .WithArgs(allArgs);
+    }
+
+    /// <summary>
+    /// Adds a Spring application to the application model. Executes the executable Spring app.
+    /// </summary>
+    /// <param name="builder">The <see cref="IDistributedApplicationBuilder"/> to add the resource to.</param>
+    /// <param name="name">The name of the resource.</param>
+    /// <param name="workingDirectory">The working directory to use for the command. If null, the working directory of the current process is used.</param>
+    /// <param name="options">The <see cref="JavaAppExecutableResourceOptions"/> to configure the Java application.</param>"
+    /// <returns>A reference to the <see cref="IResourceBuilder{T}"/>.</returns>
+    public static IResourceBuilder<JavaAppExecutableResource> AddSpringApp(this IDistributedApplicationBuilder builder, [ResourceName] string name, string workingDirectory, JavaAppExecutableResourceOptions options) =>
+        builder.AddJavaApp(name, workingDirectory, options);
+
+    /// <summary>
+    /// Adds a Maven build step to the application model.
+    /// </summary>
+    /// <param name="builder">The <see cref="IResourceBuilder{T}"/> to add the Maven build step to.</param>
+    /// <param name="mavenOptions">The <see cref="MavenOptions"/> to configure the Maven build step.</param>
+    /// <returns>A reference to the <see cref="IResourceBuilder{T}"/>.</returns>
+    /// <remarks>
+    /// This method adds a Maven build step to the application model. The Maven build step is executed before the Java application is started.
+    /// 
+    /// The Maven build step is added as an executable resource named "maven" with the command "mvnw --quiet clean package".
+    /// 
+    /// The Maven build step is excluded from the manifest file.
+    /// </remarks>
+    public static IResourceBuilder<JavaAppExecutableResource> WithMavenBuild(
+        this IResourceBuilder<JavaAppExecutableResource> builder,
+        MavenOptions? mavenOptions = null)
+    {
+        mavenOptions ??= new MavenOptions();
+        builder.ApplicationBuilder.Eventing.Subscribe<BeforeResourceStartedEvent>(builder.Resource, async (e, ct) =>
+        {
+            if (e.Resource is not JavaAppExecutableResource javaAppResource)
+            {
+                return;
+            }
+
+            var logger = e.Services.GetRequiredService<ResourceLoggerService>().GetLogger(javaAppResource);
+            var notificationService = e.Services.GetRequiredService<ResourceNotificationService>();
+
+            await notificationService.PublishUpdateAsync(javaAppResource, state => state with
+            {
+                State = new("Building Maven project", KnownResourceStates.Starting)
+            }).ConfigureAwait(false);
+
+            logger.LogInformation("Building Maven project");
+
+            var isWindows = RuntimeInformation.IsOSPlatform(OSPlatform.Windows);
+
+            var mvnw = new Process
+            {
+                StartInfo = new ProcessStartInfo
+                {
+                    FileName = isWindows ? "cmd" : "sh",
+                    Arguments = isWindows ? $"/c {mavenOptions.Command} {string.Join(" ", mavenOptions.Args)}" : $"./{mavenOptions.Command} {string.Join(" ", mavenOptions.Args)}",
+                    WorkingDirectory = mavenOptions.WorkingDirectory ?? javaAppResource.WorkingDirectory,
+                    RedirectStandardOutput = true,
+                    RedirectStandardError = true,
+                    CreateNoWindow = true,
+                    UseShellExecute = false,
+                }
+            };
+
+            mvnw.OutputDataReceived += async (sender, args) =>
+            {
+                if (!string.IsNullOrWhiteSpace(args.Data))
+                {
+                    await notificationService.PublishUpdateAsync(javaAppResource, state => state with
+                    {
+                        State = new(args.Data, KnownResourceStates.Starting)
+                    }).ConfigureAwait(false);
+
+                    logger.LogInformation("{Data}", args.Data);
+                }
+            };
+
+            mvnw.ErrorDataReceived += async (sender, args) =>
+            {
+                if (!string.IsNullOrWhiteSpace(args.Data))
+                {
+                    await notificationService.PublishUpdateAsync(javaAppResource, state => state with
+                    {
+                        State = new(args.Data, KnownResourceStates.FailedToStart)
+                    }).ConfigureAwait(false);
+
+                    logger.LogError("{Data}", args.Data);
+                }
+            };
+
+            mvnw.Start();
+            mvnw.BeginOutputReadLine();
+            mvnw.BeginErrorReadLine();
+
+            await mvnw.WaitForExitAsync(ct).ConfigureAwait(false);
+
+            if (mvnw.ExitCode != 0)
+            {
+                await notificationService.PublishUpdateAsync(javaAppResource, state => state with
+                {
+                    State = new($"mvnw exited with {mvnw.ExitCode}", KnownResourceStates.FailedToStart)
+                }).ConfigureAwait(false);
+
+                throw new InvalidOperationException($"mvnw build failed with exit code {mvnw.ExitCode}");
+            }
+        });
+
+        return builder;
+    }
+
+    private static IResourceBuilder<JavaAppExecutableResource> WithJavaDefaults(
+        this IResourceBuilder<JavaAppExecutableResource> builder,
+        JavaAppExecutableResourceOptions options) =>
+        builder.WithOtlpExporter()
+               .WithEnvironment("JAVA_TOOL_OPTIONS", $"-javaagent:{options.OtelAgentPath?.TrimEnd('/')}/opentelemetry-javaagent.jar")
+               .WithEnvironment("SERVER_PORT", options.Port.ToString(CultureInfo.InvariantCulture));
+}

src/CommunityToolkit.Aspire.Hosting.Java/MavenOptions.cs

@@ -0,0 +1,20 @@
+namespace Aspire.Hosting;
+
+/// <summary>
+/// Represents the options for configuring a Maven build step.
+/// </summary>
+public sealed class MavenOptions
+{
+    /// <summary>
+    /// Gets or sets the working directory to use for the command. If null, the working directory of the current process is used.
+    /// </summary>
+    public string? WorkingDirectory { get; set; }
+    /// <summary>
+    /// Gets or sets the command to execute. Default is "mvnw".
+    /// </summary>
+    public string Command { get; set; } = "mvnw";
+    /// <summary>
+    /// Gets or sets the arguments to pass to the command. Default is "--quiet clean package".
+    /// </summary>
+    public string[] Args { get; set; } = ["--quiet", "clean", "package"];
+}

src/CommunityToolkit.Aspire.Hosting.Java/PublicAPI.Unshipped.txt

@@ -1,2 +1,10 @@
 #nullable enable
-
+static Aspire.Hosting.JavaAppHostingExtension.WithMavenBuild(this Aspire.Hosting.ApplicationModel.IResourceBuilder<Aspire.Hosting.ApplicationModel.JavaAppExecutableResource!>! builder, Aspire.Hosting.MavenOptions? mavenOptions = null) -> Aspire.Hosting.ApplicationModel.IResourceBuilder<Aspire.Hosting.ApplicationModel.JavaAppExecutableResource!>!
+Aspire.Hosting.MavenOptions
+Aspire.Hosting.MavenOptions.MavenOptions() -> void
+Aspire.Hosting.MavenOptions.WorkingDirectory.get -> string?
+Aspire.Hosting.MavenOptions.WorkingDirectory.set -> void
+Aspire.Hosting.MavenOptions.Command.get -> string!
+Aspire.Hosting.MavenOptions.Command.set -> void
+Aspire.Hosting.MavenOptions.Args.get -> string![]!
+Aspire.Hosting.MavenOptions.Args.set -> void