Handle polyglot settings package versions on read path

playground/polyglot/TypeScript/Aspire.Hosting.Azure.Storage/ValidationAppHost/.aspire/settings.json

@@ -1,9 +1,7 @@
 {
   "appHostPath": "../apphost.ts",
   "language": "typescript/nodejs",
-  "channel": "pr-13970",
-  "sdkVersion": "13.2.0-pr.13970.g9fb24263",
   "packages": {
-    "Aspire.Hosting.Azure.Storage": "13.2.0-pr.13970.g9fb24263"
+    "Aspire.Hosting.Azure.Storage": ""
   }
-}
+}

playground/polyglot/TypeScript/Aspire.Hosting.RabbitMQ/ValidationAppHost/.aspire/settings.json

@@ -1,9 +1,7 @@
 {
   "appHostPath": "../apphost.ts",
   "language": "typescript/nodejs",
-  "channel": "local",
-  "sdkVersion": "13.2.0-preview.1.26081.1",
   "packages": {
-    "Aspire.Hosting.RabbitMQ": "13.2.0-preview.1.26081.1"
+    "Aspire.Hosting.RabbitMQ": ""
   }
-}
+}

playground/polyglot/TypeScript/Aspire.Hosting.SqlServer/.aspire/settings.json

@@ -1,9 +1,7 @@
 {
   "appHostPath": "../apphost.ts",
   "language": "typescript/nodejs",
-  "channel": "pr-13970",
-  "sdkVersion": "13.1.0",
   "packages": {
-    "Aspire.Hosting.SqlServer": "13.2.0-pr.13970.g0575147c"
+    "Aspire.Hosting.SqlServer": ""
   }
-}
+}

src/Aspire.Cli/Commands/AddCommand.cs

@@ -100,8 +100,13 @@ protected override async Task<int> ExecuteAsync(ParseResult parseResult, Cancell
             string? configuredChannel = null;
             if (project.LanguageId != KnownLanguageId.CSharp)
             {
-                var settings = AspireJsonConfiguration.Load(effectiveAppHostProjectFile.Directory!.FullName);
-                configuredChannel = settings?.Channel;
+                var appHostDirectory = effectiveAppHostProjectFile.Directory!.FullName;
+                var isProjectReferenceMode = AspireRepositoryDetector.DetectRepositoryRoot(appHostDirectory) is not null;
+                if (!isProjectReferenceMode)
+                {
+                    var settings = AspireJsonConfiguration.Load(appHostDirectory);
+                    configuredChannel = settings?.Channel;
+                }
             }
 
             var packagesWithChannels = await InteractionService.ShowStatusAsync(

src/Aspire.Cli/Commands/UpdateCommand.cs

@@ -146,13 +146,22 @@ protected override async Task<int> ExecuteAsync(ParseResult parseResult, Cancell
                 return ExitCodeConstants.FailedToFindProject;
             }
 
-            var allChannels = await _packagingService.GetChannelsAsync(cancellationToken);
+            var project = _projectFactory.GetProject(projectFile);
+            var isGuestProject = !project.LanguageId.Equals(KnownLanguageId.CSharp, StringComparison.OrdinalIgnoreCase);
+            var isProjectReferenceMode = isGuestProject && AspireRepositoryDetector.DetectRepositoryRoot(projectFile.Directory?.FullName) is not null;
 
             // Check if channel or quality option was provided (channel takes precedence)
             var channelName = parseResult.GetValue(_channelOption) ?? parseResult.GetValue(_qualityOption);
             PackageChannel channel;
 
-            if (!string.IsNullOrEmpty(channelName))
+            var allChannels = await _packagingService.GetChannelsAsync(cancellationToken);
+
+            if (isProjectReferenceMode)
+            {
+                channel = allChannels.FirstOrDefault(c => c.Type is PackageChannelType.Implicit)
+                    ?? allChannels.First();
+            }
+            else if (!string.IsNullOrEmpty(channelName))
             {
                 // Try to find a channel matching the provided channel/quality
                 channel = allChannels.FirstOrDefault(c => string.Equals(c.Name, channelName, StringComparison.OrdinalIgnoreCase))
@@ -181,8 +190,7 @@ protected override async Task<int> ExecuteAsync(ParseResult parseResult, Cancell
                 }
             }
 
-            // Get the appropriate project handler and update packages
-            var project = _projectFactory.GetProject(projectFile);
+            // Update packages using the appropriate project handler
             var updateContext = new UpdatePackagesContext
             {
                 AppHostFile = projectFile,

src/Aspire.Cli/Configuration/AspireJsonConfiguration.cs

@@ -163,32 +163,56 @@ public bool RemovePackage(string packageId)
     }
 
     /// <summary>
-    /// Gets all package references including the base Aspire.Hosting packages.
-    /// Uses the SdkVersion for base packages.
-    /// Note: Aspire.Hosting.AppHost is an SDK package (not a runtime DLL) and is excluded.
+    /// Gets the effective SDK version for package-based AppHost preparation.
+    /// Falls back to <paramref name="defaultSdkVersion"/> when no SDK version is configured.
     /// </summary>
+    public string GetEffectiveSdkVersion(string defaultSdkVersion)
+    {
+        return string.IsNullOrWhiteSpace(SdkVersion) ? defaultSdkVersion : SdkVersion;
+    }
+
+    /// <summary>
+    /// Gets all package references including the base Aspire.Hosting package.
+    /// Empty package versions in settings are resolved to the effective SDK version.
+    /// </summary>
+    /// <param name="defaultSdkVersion">Default SDK version to use when not configured.</param>
+    /// <param name="useProjectReferences">Unused compatibility parameter.</param>
     /// <returns>Enumerable of (PackageName, Version) tuples.</returns>
-    public IEnumerable<(string Name, string Version)> GetAllPackages()
+    public IEnumerable<(string Name, string Version)> GetAllPackages(string defaultSdkVersion, bool useProjectReferences)
     {
-        var sdkVersion = SdkVersion ?? throw new InvalidOperationException("SdkVersion must be set before calling GetAllPackages. Use LoadOrCreate to ensure it's set.");
+        _ = useProjectReferences;
+        var sdkVersion = GetEffectiveSdkVersion(defaultSdkVersion);
 
-        // Base packages always included (Aspire.Hosting.AppHost is an SDK, not a runtime DLL)
+        // Base package always included (Aspire.Hosting.AppHost is an SDK, not a runtime DLL)
         yield return ("Aspire.Hosting", sdkVersion);
 
-        // Additional packages from settings
-        if (Packages is not null)
+        if (Packages is null)
+        {
+            yield break;
+        }
+
+        foreach (var (packageName, version) in Packages)
         {
-            foreach (var (packageName, version) in Packages)
+            // Skip base packages and SDK-only packages
+            if (string.Equals(packageName, "Aspire.Hosting", StringComparison.OrdinalIgnoreCase) ||
+                string.Equals(packageName, "Aspire.Hosting.AppHost", StringComparison.OrdinalIgnoreCase))
             {
-                // Skip base packages and SDK-only packages
-                if (string.Equals(packageName, "Aspire.Hosting", StringComparison.OrdinalIgnoreCase) ||
-                    string.Equals(packageName, "Aspire.Hosting.AppHost", StringComparison.OrdinalIgnoreCase))
-                {
-                    continue;
-                }
-
-                yield return (packageName, version);
+                continue;
             }
+
+            yield return (packageName, string.IsNullOrWhiteSpace(version) ? sdkVersion : version);
         }
     }
+
+    /// <summary>
+    /// Gets all package references including the base Aspire.Hosting packages.
+    /// Uses the SdkVersion for base packages.
+    /// Note: Aspire.Hosting.AppHost is an SDK package (not a runtime DLL) and is excluded.
+    /// </summary>
+    /// <returns>Enumerable of (PackageName, Version) tuples.</returns>
+    public IEnumerable<(string Name, string Version)> GetAllPackages()
+    {
+        var sdkVersion = SdkVersion ?? throw new InvalidOperationException("SdkVersion must be set before calling GetAllPackages. Use LoadOrCreate to ensure it's set.");
+        return GetAllPackages(sdkVersion, useProjectReferences: false);
+    }
 }

src/Aspire.Cli/Projects/AppHostServerProject.cs

@@ -8,6 +8,7 @@
 using Aspire.Cli.DotNet;
 using Aspire.Cli.NuGet;
 using Aspire.Cli.Packaging;
+using Aspire.Cli.Utils;
 using Microsoft.Extensions.Logging;
 
 namespace Aspire.Cli.Projects;
@@ -58,7 +59,7 @@ public async Task<IAppHostServerProject> CreateAsync(string appPath, Cancellatio
         }
 
         // Priority 1: Check for dev mode (ASPIRE_REPO_ROOT or running from Aspire source repo)
-        var repoRoot = DetectAspireRepoRoot();
+        var repoRoot = AspireRepositoryDetector.DetectRepositoryRoot(appPath);
         if (repoRoot is not null)
         {
             return new DotNetBasedAppHostServerProject(
@@ -91,40 +92,4 @@ public async Task<IAppHostServerProject> CreateAsync(string appPath, Cancellatio
             "No Aspire AppHost server is available. Ensure the Aspire CLI is installed " +
             "with a valid bundle layout, or reinstall using 'aspire setup --force'.");
     }
-
-    /// <summary>
-    /// Detects the Aspire repository root for dev mode.
-    /// Checks ASPIRE_REPO_ROOT env var first, then walks up from the CLI executable
-    /// looking for a git repo containing Aspire.slnx.
-    /// </summary>
-    private static string? DetectAspireRepoRoot()
-    {
-        // Check explicit environment variable
-        var envRoot = Environment.GetEnvironmentVariable("ASPIRE_REPO_ROOT");
-        if (!string.IsNullOrEmpty(envRoot) && Directory.Exists(envRoot))
-        {
-            return envRoot;
-        }
-
-        // Auto-detect: walk up from the CLI executable looking for .git + Aspire.slnx
-        var cliPath = Environment.ProcessPath;
-        if (string.IsNullOrEmpty(cliPath))
-        {
-            return null;
-        }
-
-        var dir = Path.GetDirectoryName(cliPath);
-        while (dir is not null)
-        {
-            if (Directory.Exists(Path.Combine(dir, ".git")) &&
-                File.Exists(Path.Combine(dir, "Aspire.slnx")))
-            {
-                return dir;
-            }
-
-            dir = Path.GetDirectoryName(dir);
-        }
-
-        return null;
-    }
 }

src/Aspire.Cli/Projects/GuestAppHostProject.cs

@@ -135,15 +135,28 @@ public bool CanHandle(FileInfo appHostFile)
         AspireJsonConfiguration config,
         CancellationToken cancellationToken)
     {
-        var packages = config.GetAllPackages().ToList();
+        var defaultSdkVersion = GetEffectiveSdkVersion();
+        var packages = config.GetAllPackages(defaultSdkVersion, useProjectReferences: false).ToList();
         var codeGenPackage = await _languageDiscovery.GetPackageForLanguageAsync(_resolvedLanguage.LanguageId, cancellationToken);
         if (codeGenPackage is not null)
         {
-            packages.Add((codeGenPackage, config.SdkVersion!));
+            var codeGenVersion = config.GetEffectiveSdkVersion(defaultSdkVersion);
+            packages.Add((codeGenPackage, codeGenVersion));
         }
         return packages;
     }
 
+    private AspireJsonConfiguration LoadConfiguration(DirectoryInfo directory)
+    {
+        var effectiveSdkVersion = GetEffectiveSdkVersion();
+        return AspireJsonConfiguration.LoadOrCreate(directory.FullName, effectiveSdkVersion);
+    }
+
+    private string GetPrepareSdkVersion(AspireJsonConfiguration config)
+    {
+        return config.GetEffectiveSdkVersion(GetEffectiveSdkVersion());
+    }
+
     /// <summary>
     /// Prepares the AppHost server (creates files and builds for dev mode, restores packages for prebuilt mode).
     /// </summary>
@@ -162,14 +175,14 @@ public bool CanHandle(FileInfo appHostFile)
     /// </summary>
     private async Task BuildAndGenerateSdkAsync(DirectoryInfo directory, CancellationToken cancellationToken)
     {
+        var appHostServerProject = await _appHostServerProjectFactory.CreateAsync(directory.FullName, cancellationToken);
+
         // Step 1: Load config - source of truth for SDK version and packages
-        var effectiveSdkVersion = GetEffectiveSdkVersion();
-        var config = AspireJsonConfiguration.LoadOrCreate(directory.FullName, effectiveSdkVersion);
+        var config = LoadConfiguration(directory);
         var packages = await GetAllPackagesAsync(config, cancellationToken);
+        var sdkVersion = GetPrepareSdkVersion(config);
 
-        var appHostServerProject = await _appHostServerProjectFactory.CreateAsync(directory.FullName, cancellationToken);
-
-        var (buildSuccess, buildOutput, _, _) = await PrepareAppHostServerAsync(appHostServerProject, config.SdkVersion!, packages, cancellationToken);
+        var (buildSuccess, buildOutput, _, _) = await PrepareAppHostServerAsync(appHostServerProject, sdkVersion, packages, cancellationToken);
         if (!buildSuccess)
         {
             if (buildOutput is not null)
@@ -269,19 +282,19 @@ public async Task<int> RunAsync(AppHostProjectContext context, CancellationToken
             }
 
             // Build phase: build AppHost server (dependency install happens after server starts)
+            var appHostServerProject = await _appHostServerProjectFactory.CreateAsync(directory.FullName, cancellationToken);
+
             // Load config - source of truth for SDK version and packages
-            var effectiveSdkVersion = GetEffectiveSdkVersion();
-            var config = AspireJsonConfiguration.LoadOrCreate(directory.FullName, effectiveSdkVersion);
+            var config = LoadConfiguration(directory);
             var packages = await GetAllPackagesAsync(config, cancellationToken);
-
-            var appHostServerProject = await _appHostServerProjectFactory.CreateAsync(directory.FullName, cancellationToken);
+            var sdkVersion = GetPrepareSdkVersion(config);
 
             var buildResult = await _interactionService.ShowStatusAsync(
                 ":gear:  Preparing Aspire server...",
                 async () =>
                 {
                     // Prepare the AppHost server (build for dev mode, restore for prebuilt)
-                    var (prepareSuccess, prepareOutput, channelName, needsCodeGen) = await PrepareAppHostServerAsync(appHostServerProject, config.SdkVersion!, packages, cancellationToken);
+                    var (prepareSuccess, prepareOutput, channelName, needsCodeGen) = await PrepareAppHostServerAsync(appHostServerProject, sdkVersion, packages, cancellationToken);
                     if (!prepareSuccess)
                     {
                         return (Success: false, Output: prepareOutput, Error: "Failed to prepare app host.", ChannelName: (string?)null, NeedsCodeGen: false);
@@ -557,14 +570,13 @@ public async Task<int> PublishAsync(PublishContext context, CancellationToken ca
         try
         {
             // Step 1: Load config - source of truth for SDK version and packages
-            var effectiveSdkVersion = GetEffectiveSdkVersion();
-            var config = AspireJsonConfiguration.LoadOrCreate(directory.FullName, effectiveSdkVersion);
-            var packages = await GetAllPackagesAsync(config, cancellationToken);
-
             var appHostServerProject = await _appHostServerProjectFactory.CreateAsync(directory.FullName, cancellationToken);
+            var config = LoadConfiguration(directory);
+            var packages = await GetAllPackagesAsync(config, cancellationToken);
+            var sdkVersion = GetPrepareSdkVersion(config);
 
             // Prepare the AppHost server (build for dev mode, restore for prebuilt)
-            var (prepareSuccess, prepareOutput, _, needsCodeGen) = await PrepareAppHostServerAsync(appHostServerProject, config.SdkVersion!, packages, cancellationToken);
+            var (prepareSuccess, prepareOutput, _, needsCodeGen) = await PrepareAppHostServerAsync(appHostServerProject, sdkVersion, packages, cancellationToken);
             if (!prepareSuccess)
             {
                 // Set OutputCollector so PipelineCommandBase can display errors
@@ -802,8 +814,7 @@ public async Task<bool> AddPackageAsync(AddPackageContext context, CancellationT
         }
 
         // Load config - source of truth for SDK version and packages
-        var effectiveSdkVersion = GetEffectiveSdkVersion();
-        var config = AspireJsonConfiguration.LoadOrCreate(directory.FullName, effectiveSdkVersion);
+        var config = LoadConfiguration(directory);
 
         // Update .aspire/settings.json with the new package
         config.AddOrUpdatePackage(context.PackageId, context.PackageVersion);
@@ -825,8 +836,7 @@ public async Task<UpdatePackagesResult> UpdatePackagesAsync(UpdatePackagesContex
         }
 
         // Load config - source of truth for SDK version and packages
-        var effectiveSdkVersion = GetEffectiveSdkVersion();
-        var config = AspireJsonConfiguration.LoadOrCreate(directory.FullName, effectiveSdkVersion);
+        var config = LoadConfiguration(directory);
 
         // Find updates for SDK version and packages
         string? newSdkVersion = null;

src/Aspire.Cli/Projects/ProjectLocator.cs

@@ -314,7 +314,7 @@ private async Task CreateSettingsFileAsync(FileInfo projectFile, CancellationTok
         if (language is not null && !language.LanguageId.Value.Equals(KnownLanguageId.CSharp, StringComparison.OrdinalIgnoreCase))
         {
             await configurationService.SetConfigurationAsync("language", language.LanguageId.Value, isGlobal: false, cancellationToken);
-            
+
             // Inherit SDK version from parent/global config if available
             var inheritedSdkVersion = await configurationService.GetConfigurationAsync("sdkVersion", cancellationToken);
             if (!string.IsNullOrEmpty(inheritedSdkVersion))

src/Aspire.Cli/Scaffolding/ScaffoldingService.cs

@@ -55,25 +55,25 @@ private async Task ScaffoldGuestLanguageAsync(ScaffoldContext context, Cancellat
         var directory = context.TargetDirectory;
         var language = context.Language;
 
-        // Step 1: Resolve SDK version from channel (if configured) or use default
+        // Step 1: Resolve SDK and package strategy
         var sdkVersion = await ResolveSdkVersionAsync(cancellationToken);
-
-        // Load or create config with resolved SDK version
         var config = AspireJsonConfiguration.LoadOrCreate(directory.FullName, sdkVersion);
 
         // Include the code generation package for scaffolding and code gen
         var codeGenPackage = await _languageDiscovery.GetPackageForLanguageAsync(language.LanguageId, cancellationToken);
-        var packages = config.GetAllPackages().ToList();
+        var packages = config.GetAllPackages(sdkVersion, useProjectReferences: false).ToList();
         if (codeGenPackage is not null)
         {
-            packages.Add((codeGenPackage, config.SdkVersion!));
+            var codeGenVersion = config.GetEffectiveSdkVersion(sdkVersion);
+            packages.Add((codeGenPackage, codeGenVersion));
         }
 
         var appHostServerProject = await _appHostServerProjectFactory.CreateAsync(directory.FullName, cancellationToken);
+        var prepareSdkVersion = config.GetEffectiveSdkVersion(sdkVersion);
 
         var prepareResult = await _interactionService.ShowStatusAsync(
             ":gear:  Preparing Aspire server...",
-            () => appHostServerProject.PrepareAsync(config.SdkVersion!, packages, cancellationToken));
+            () => appHostServerProject.PrepareAsync(prepareSdkVersion, packages, cancellationToken));
         if (!prepareResult.Success)
         {
             if (prepareResult.Output is not null)
@@ -134,6 +134,7 @@ await GenerateCodeViaRpcAsync(
             {
                 config.Channel = prepareResult.ChannelName;
             }
+
             config.Language = language.LanguageId;
             config.Save(directory.FullName);
         }