Refactor user secrets to DI-based factory with thread-safe synchronization

src/Aspire.Hosting/ApplicationModel/UserSecretsParameterDefault.cs

@@ -4,7 +4,7 @@
 using System.Diagnostics;
 using System.Reflection;
 using Aspire.Hosting.Publishing;
-using Microsoft.Extensions.SecretManager.Tools.Internal;
+using Aspire.Hosting.UserSecrets;
 
 namespace Aspire.Hosting.ApplicationModel;
 
@@ -15,15 +15,23 @@ namespace Aspire.Hosting.ApplicationModel;
 /// <param name="applicationName">The application name.</param>
 /// <param name="parameterName">The parameter name.</param>
 /// <param name="parameterDefault">The <see cref="ParameterDefault"/> that will produce the default value when it isn't found in the project's user secrets store.</param>
-internal sealed class UserSecretsParameterDefault(Assembly appHostAssembly, string applicationName, string parameterName, ParameterDefault parameterDefault)
+/// <param name="factory">The factory to use for creating user secrets managers.</param>
+internal sealed class UserSecretsParameterDefault(Assembly appHostAssembly, string applicationName, string parameterName, ParameterDefault parameterDefault, UserSecretsManagerFactory factory)
     : ParameterDefault
 {
+    public UserSecretsParameterDefault(Assembly appHostAssembly, string applicationName, string parameterName, ParameterDefault parameterDefault)
+        : this(appHostAssembly, applicationName, parameterName, parameterDefault, UserSecretsManagerFactory.Instance)
+    {
+    }
+
     /// <inheritdoc/>
     public override string GetDefaultValue()
     {
         var value = parameterDefault.GetDefaultValue();
         var configurationKey = $"Parameters:{parameterName}";
-        if (!SecretsStore.TrySetUserSecret(appHostAssembly, configurationKey, value))
+
+        var manager = factory.GetOrCreate(appHostAssembly);
+        if (!manager.TrySetSecret(configurationKey, value))
         {
             // This is a best-effort operation, so we don't throw if it fails. Common reason for failure is that the user secrets ID is not set
             // in the application's assembly. Note there's no ILogger available this early in the application lifecycle.

src/Aspire.Hosting/Aspire.Hosting.csproj

@@ -31,7 +31,6 @@
     <Compile Include="$(SharedDir)LoggingHelpers.cs" Link="Utils\LoggingHelpers.cs" />
     <Compile Include="$(SharedDir)StringUtils.cs" Link="Utils\StringUtils.cs" />
     <Compile Include="$(SharedDir)SchemaUtils.cs" Link="Utils\SchemaUtils.cs" />
-    <Compile Include="$(SharedDir)SecretsStore.cs" Link="Utils\SecretsStore.cs" />
     <Compile Include="$(SharedDir)ConsoleLogs\LogEntries.cs" Link="Utils\ConsoleLogs\LogEntries.cs" />
     <Compile Include="$(SharedDir)ConsoleLogs\LogEntry.cs" Link="Utils\ConsoleLogs\LogEntry.cs" />
     <Compile Include="$(SharedDir)ConsoleLogs\LogPauseViewModel.cs" Link="Utils\ConsoleLogs\LogPauseViewModel.cs" />

src/Aspire.Hosting/DistributedApplicationBuilder.cs

@@ -26,6 +26,7 @@
 using Aspire.Hosting.Pipelines;
 using Aspire.Hosting.Pipelines.Internal;
 using Aspire.Hosting.Publishing;
+using Aspire.Hosting.UserSecrets;
 using Aspire.Hosting.VersionChecking;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
@@ -34,7 +35,6 @@
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
-using Microsoft.Extensions.SecretManager.Tools.Internal;
 
 namespace Aspire.Hosting;
 
@@ -64,6 +64,7 @@ public class DistributedApplicationBuilder : IDistributedApplicationBuilder
 
     private readonly DistributedApplicationOptions _options;
     private readonly HostApplicationBuilder _innerBuilder;
+    private readonly IUserSecretsManager _userSecretsManager;
 
     /// <inheritdoc />
     public IHostEnvironment Environment => _innerBuilder.Environment;
@@ -288,6 +289,11 @@ public DistributedApplicationBuilder(DistributedApplicationOptions options)
         }
 
         // Core things
+        // Create and register the user secrets manager
+        _userSecretsManager = UserSecretsManagerFactory.Instance.GetOrCreate(AppHostAssembly);
+        // Always register IUserSecretsManager so dependencies can resolve
+        _innerBuilder.Services.AddSingleton(_userSecretsManager);
+
         _innerBuilder.Services.AddSingleton(sp => new DistributedApplicationModel(Resources));
         _innerBuilder.Services.AddSingleton<PipelineExecutor>();
         _innerBuilder.Services.AddHostedService<PipelineExecutor>(sp => sp.GetRequiredService<PipelineExecutor>());
@@ -356,13 +362,13 @@ public DistributedApplicationBuilder(DistributedApplicationOptions options)
                     // If a key is generated, it's stored in the user secrets store so that it will be auto-loaded
                     // on subsequent runs and not recreated. This is important to ensure it doesn't change the state
                     // of persistent containers (as a new key would be a spec change).
-                    SecretsStore.GetOrSetUserSecret(_innerBuilder.Configuration, AppHostAssembly, "AppHost:OtlpApiKey", TokenGenerator.GenerateToken);
+                    _userSecretsManager.GetOrSetSecret(_innerBuilder.Configuration, "AppHost:OtlpApiKey", TokenGenerator.GenerateToken);
 
                     // Set a random API key for the MCP Server if one isn't already present in configuration.
                     // If a key is generated, it's stored in the user secrets store so that it will be auto-loaded
                     // on subsequent runs and not recreated. This is important to ensure it doesn't change the state
                     // of MCP clients.
-                    SecretsStore.GetOrSetUserSecret(_innerBuilder.Configuration, AppHostAssembly, "AppHost:McpApiKey", TokenGenerator.GenerateToken);
+                    _userSecretsManager.GetOrSetSecret(_innerBuilder.Configuration, "AppHost:McpApiKey", TokenGenerator.GenerateToken);
 
                     // Determine the frontend browser token.
                     if (_innerBuilder.Configuration.GetString(KnownConfigNames.DashboardFrontendBrowserToken,

src/Aspire.Hosting/Pipelines/Internal/DeploymentStateManagerBase.cs

@@ -61,87 +61,6 @@ private sealed class SectionMetadata(long version)
     /// <param name="cancellationToken">Cancellation token.</param>
     protected abstract Task SaveStateToStorageAsync(JsonObject state, CancellationToken cancellationToken);
 
-    /// <summary>
-    /// Flattens a JsonObject using colon-separated keys for configuration compatibility.
-    /// Handles both nested objects and arrays with indexed keys.
-    /// </summary>
-    /// <param name="source">The source JsonObject to flatten.</param>
-    /// <returns>A flattened JsonObject.</returns>
-    public static JsonObject FlattenJsonObject(JsonObject source)
-    {
-        var result = new JsonObject();
-        FlattenJsonObjectRecursive(source, string.Empty, result);
-        return result;
-    }
-
-    /// <summary>
-    /// Unflattens a JsonObject that uses colon-separated keys back into a nested structure.
-    /// Handles both nested objects and arrays with indexed keys.
-    /// </summary>
-    /// <param name="source">The flattened JsonObject to unflatten.</param>
-    /// <returns>An unflattened JsonObject with nested structure.</returns>
-    public static JsonObject UnflattenJsonObject(JsonObject source)
-    {
-        var result = new JsonObject();
-
-        foreach (var kvp in source)
-        {
-            var keys = kvp.Key.Split(':');
-            var current = result;
-
-            for (var i = 0; i < keys.Length - 1; i++)
-            {
-                var key = keys[i];
-                if (!current.TryGetPropertyValue(key, out var existing) || existing is not JsonObject)
-                {
-                    var newObject = new JsonObject();
-                    current[key] = newObject;
-                    current = newObject;
-                }
-                else
-                {
-                    current = existing.AsObject();
-                }
-            }
-
-            current[keys[^1]] = kvp.Value?.DeepClone();
-        }
-
-        return result;
-    }
-
-    private static void FlattenJsonObjectRecursive(JsonObject source, string prefix, JsonObject result)
-    {
-        foreach (var kvp in source)
-        {
-            var key = string.IsNullOrEmpty(prefix) ? kvp.Key : $"{prefix}:{kvp.Key}";
-
-            if (kvp.Value is JsonObject nestedObject)
-            {
-                FlattenJsonObjectRecursive(nestedObject, key, result);
-            }
-            else if (kvp.Value is JsonArray array)
-            {
-                for (var i = 0; i < array.Count; i++)
-                {
-                    var arrayKey = $"{key}:{i}";
-                    if (array[i] is JsonObject arrayObject)
-                    {
-                        FlattenJsonObjectRecursive(arrayObject, arrayKey, result);
-                    }
-                    else
-                    {
-                        result[arrayKey] = array[i]?.DeepClone();
-                    }
-                }
-            }
-            else
-            {
-                result[key] = kvp.Value?.DeepClone();
-            }
-        }
-    }
-
     /// <summary>
     /// Loads the deployment state from storage, using caching to avoid repeated loads.
     /// </summary>
@@ -169,7 +88,7 @@ protected async Task<JsonObject> LoadStateAsync(CancellationToken cancellationTo
             {
                 var fileContent = await File.ReadAllTextAsync(statePath, cancellationToken).ConfigureAwait(false);
                 var flattenedState = JsonNode.Parse(fileContent, documentOptions: jsonDocumentOptions)!.AsObject();
-                _state = UnflattenJsonObject(flattenedState);
+                _state = JsonFlattener.UnflattenJsonObject(flattenedState);
             }
             else
             {

src/Aspire.Hosting/Pipelines/Internal/FileDeploymentStateManager.cs

@@ -63,7 +63,7 @@ protected override async Task SaveStateToStorageAsync(JsonObject state, Cancella
                 return;
             }
 
-            var flattenedSecrets = FlattenJsonObject(state);
+            var flattenedSecrets = JsonFlattener.FlattenJsonObject(state);
             Directory.CreateDirectory(Path.GetDirectoryName(deploymentStatePath)!);
             await File.WriteAllTextAsync(
                 deploymentStatePath,

src/Aspire.Hosting/Pipelines/Internal/JsonFlattener.cs

@@ -0,0 +1,93 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Text.Json.Nodes;
+
+namespace Aspire.Hosting.Pipelines.Internal;
+
+/// <summary>
+/// Provides utility methods for flattening and unflattening JSON objects using colon-separated keys.
+/// </summary>
+internal static class JsonFlattener
+{
+    /// <summary>
+    /// Flattens a JsonObject using colon-separated keys for configuration compatibility.
+    /// Handles both nested objects and arrays with indexed keys.
+    /// </summary>
+    /// <param name="source">The source JsonObject to flatten.</param>
+    /// <returns>A flattened JsonObject.</returns>
+    public static JsonObject FlattenJsonObject(JsonObject source)
+    {
+        var result = new JsonObject();
+        FlattenJsonObjectRecursive(source, string.Empty, result);
+        return result;
+    }
+
+    /// <summary>
+    /// Unflattens a JsonObject that uses colon-separated keys back into a nested structure.
+    /// Handles both nested objects and arrays with indexed keys.
+    /// </summary>
+    /// <param name="source">The flattened JsonObject to unflatten.</param>
+    /// <returns>An unflattened JsonObject with nested structure.</returns>
+    public static JsonObject UnflattenJsonObject(JsonObject source)
+    {
+        var result = new JsonObject();
+
+        foreach (var kvp in source)
+        {
+            var keys = kvp.Key.Split(':');
+            var current = result;
+
+            for (var i = 0; i < keys.Length - 1; i++)
+            {
+                var key = keys[i];
+                if (!current.TryGetPropertyValue(key, out var existing) || existing is not JsonObject)
+                {
+                    var newObject = new JsonObject();
+                    current[key] = newObject;
+                    current = newObject;
+                }
+                else
+                {
+                    current = existing.AsObject();
+                }
+            }
+
+            current[keys[^1]] = kvp.Value?.DeepClone();
+        }
+
+        return result;
+    }
+
+    private static void FlattenJsonObjectRecursive(JsonObject source, string prefix, JsonObject result)
+    {
+        foreach (var kvp in source)
+        {
+            var key = string.IsNullOrEmpty(prefix) ? kvp.Key : $"{prefix}:{kvp.Key}";
+
+            if (kvp.Value is JsonObject nestedObject)
+            {
+                FlattenJsonObjectRecursive(nestedObject, key, result);
+            }
+            else if (kvp.Value is JsonArray array)
+            {
+                for (var i = 0; i < array.Count; i++)
+                {
+                    var arrayKey = $"{key}:{i}";
+                    if (array[i] is JsonObject arrayObject)
+                    {
+                        FlattenJsonObjectRecursive(arrayObject, arrayKey, result);
+                    }
+                    else
+                    {
+                        result[arrayKey] = array[i]?.DeepClone();
+                    }
+                }
+            }
+            else
+            {
+                result[key] = kvp.Value?.DeepClone();
+            }
+        }
+    }
+}

src/Aspire.Hosting/Pipelines/Internal/UserSecretsDeploymentStateManager.cs

@@ -3,42 +3,42 @@
 
 #pragma warning disable ASPIREPIPELINES002 // Type is for evaluation purposes only and is subject to change or removal in future updates. Suppress this diagnostic to proceed.
 
-using System.Reflection;
 using System.Text.Json;
 using System.Text.Json.Nodes;
-using Microsoft.Extensions.Configuration.UserSecrets;
+using Aspire.Hosting.UserSecrets;
 using Microsoft.Extensions.Logging;
 
 namespace Aspire.Hosting.Pipelines.Internal;
 
 /// <summary>
 /// User secrets implementation of <see cref="IDeploymentStateManager"/>.
 /// </summary>
-internal sealed class UserSecretsDeploymentStateManager(ILogger<UserSecretsDeploymentStateManager> logger) : DeploymentStateManagerBase<UserSecretsDeploymentStateManager>(logger)
+internal sealed class UserSecretsDeploymentStateManager : DeploymentStateManagerBase<UserSecretsDeploymentStateManager>
 {
+    private readonly IUserSecretsManager _userSecretsManager;
+
+    public UserSecretsDeploymentStateManager(ILogger<UserSecretsDeploymentStateManager> logger, IUserSecretsManager userSecretsManager)
+        : base(logger)
+    {
+        _userSecretsManager = userSecretsManager;
+    }
+
     /// <inheritdoc/>
     public override string? StateFilePath => GetStatePath();
 
     /// <inheritdoc/>
     protected override string? GetStatePath()
     {
-        return Assembly.GetEntryAssembly()?.GetCustomAttribute<UserSecretsIdAttribute>()?.UserSecretsId switch
-        {
-            null => Environment.GetEnvironmentVariable("DOTNET_USER_SECRETS_ID"),
-            string id => UserSecretsPathHelper.GetSecretsPathFromSecretsId(id)
-        };
+        return _userSecretsManager.FilePath;
     }
 
     /// <inheritdoc/>
     protected override async Task SaveStateToStorageAsync(JsonObject state, CancellationToken cancellationToken)
     {
         try
         {
-            var userSecretsPath = GetStatePath() ?? throw new InvalidOperationException("User secrets path could not be determined.");
-            var flattenedUserSecrets = DeploymentStateManagerBase<UserSecretsDeploymentStateManager>.FlattenJsonObject(state);
-            Directory.CreateDirectory(Path.GetDirectoryName(userSecretsPath)!);
-            await File.WriteAllTextAsync(userSecretsPath, flattenedUserSecrets.ToJsonString(s_jsonSerializerOptions), cancellationToken).ConfigureAwait(false);
-
+            // Use the shared manager which handles locking
+            await _userSecretsManager.SaveStateAsync(state, cancellationToken).ConfigureAwait(false);
             logger.LogInformation("Azure resource connection strings saved to user secrets.");
         }
         catch (JsonException ex)

src/Aspire.Hosting/UserSecrets/IUserSecretsManager.cs

@@ -0,0 +1,42 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Text.Json.Nodes;
+using Microsoft.Extensions.Configuration;
+
+namespace Aspire.Hosting.UserSecrets;
+
+/// <summary>
+/// Defines an interface for managing user secrets with support for read and write operations.
+/// </summary>
+internal interface IUserSecretsManager
+{
+    /// <summary>
+    /// Gets the path to the user secrets file.
+    /// </summary>
+    string FilePath { get; }
+
+    /// <summary>
+    /// Attempts to set a user secret value synchronously.
+    /// </summary>
+    /// <param name="name">The name of the secret.</param>
+    /// <param name="value">The value of the secret.</param>
+    /// <returns>True if the secret was set successfully; otherwise, false.</returns>
+    bool TrySetSecret(string name, string value);
+
+    /// <summary>
+    /// Gets a secret value if it exists in configuration, or sets it using the value generator if it doesn't.
+    /// </summary>
+    /// <param name="configuration">The configuration manager to check and update.</param>
+    /// <param name="name">The name of the secret.</param>
+    /// <param name="valueGenerator">Function to generate the value if it doesn't exist.</param>
+    void GetOrSetSecret(IConfigurationManager configuration, string name, Func<string> valueGenerator);
+
+    /// <summary>
+    /// Saves state to user secrets asynchronously (for deployment state manager).
+    /// If multiple callers save state concurrently, the last write wins.
+    /// </summary>
+    /// <param name="state">The state to save as a JSON object.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    Task SaveStateAsync(JsonObject state, CancellationToken cancellationToken = default);
+}