feat: 实现动态租户解析与移除菜单回退逻辑

1. 新增 ITenantCodeResolver 接口和 DatabaseTenantCodeResolver 实现
2. 修改 TenantResolutionMiddleware 支持从数据库动态解析租户编码
3. ITenantRepository 新增 FindIdByCodeAsync 方法
4. 移除 EfMenuRepository 中危险的系统菜单回退逻辑
5. 调整服务注册顺序确保依赖正确注入

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/Api/TakeoutSaaS.TenantApi/Program.cs

@@ -85,8 +85,7 @@ if (isDevelopment)
     });
 }
 
-// 5. 注册多租户解析、鉴权授权与权限策略
+// 5. 注册鉴权授权与权限策略
-builder.Services.AddTenantResolution(builder.Configuration);
 builder.Services.AddJwtAuthentication(builder.Configuration);
 builder.Services.AddAuthorization();
 builder.Services.AddPermissionAuthorization();
@@ -98,6 +97,9 @@ builder.Services.AddIdentityApplication(enableMiniSupport: false);
 builder.Services.AddAppInfrastructure(builder.Configuration);
 builder.Services.AddIdentityInfrastructure(builder.Configuration, enableMiniFeatures: false, enableAdminSeed: false);
 
+// 7. 注册多租户解析（依赖 ITenantRepository，需在 Infrastructure 之后）
+builder.Services.AddTenantResolution(builder.Configuration);
+
 // 6. (空行后) 注册字典模块（系统参数、字典项、缓存等）
 builder.Services.AddDictionaryApplication();
 builder.Services.AddDictionaryInfrastructure(builder.Configuration);

src/Api/TakeoutSaaS.TenantApi/appsettings.Development.json

@@ -56,7 +56,9 @@
       "/health",
       "/healthz"
     ],
-    "RootDomain": ""
+    "RootDomain": "laosankeji.com",
+    "CodeTenantMap": {},
+    "ThrowIfUnresolved": false
   },
   "Cors": {
     "Tenant": []

src/Domain/TakeoutSaaS.Domain/Tenants/Repositories/ITenantRepository.cs

@@ -84,6 +84,14 @@ public interface ITenantRepository
     /// <returns>存在返回 true，否则 false。</returns>
     Task<bool> ExistsByCodeAsync(string code, CancellationToken cancellationToken = default);
 
+    /// <summary>
+    /// 依据租户编码查询租户 ID。
+    /// </summary>
+    /// <param name="code">租户编码。</param>
+    /// <param name="cancellationToken">取消标记。</param>
+    /// <returns>租户 ID，未找到返回 null。</returns>
+    Task<long?> FindIdByCodeAsync(string code, CancellationToken cancellationToken = default);
+
     /// <summary>
     /// 判断租户名称是否存在（支持排除指定租户）。
     /// </summary>

src/Infrastructure/TakeoutSaaS.Infrastructure/App/Repositories/EfTenantRepository.cs

@@ -162,6 +162,20 @@ public sealed class EfTenantRepository(TakeoutAppDbContext context, TakeoutLogsD
         return context.Tenants.AnyAsync(x => x.Code == normalized, cancellationToken);
     }
 
+    /// <inheritdoc />
+    public Task<long?> FindIdByCodeAsync(string code, CancellationToken cancellationToken = default)
+    {
+        // 1. 标准化编码
+        var normalized = code.Trim();
+
+        // 2. 查询租户 ID（仅查询未删除且状态正常的租户）
+        return context.Tenants
+            .AsNoTracking()
+            .Where(x => x.Code == normalized && x.DeletedAt == null)
+            .Select(x => (long?)x.Id)
+            .FirstOrDefaultAsync(cancellationToken);
+    }
+
     /// <inheritdoc />
     public Task<bool> ExistsByNameAsync(string name, long? excludeTenantId = null, CancellationToken cancellationToken = default)
     {

src/Infrastructure/TakeoutSaaS.Infrastructure/Identity/Repositories/EfMenuRepository.cs

@@ -2,65 +2,37 @@ using Microsoft.EntityFrameworkCore;
 using TakeoutSaaS.Domain.Identity.Entities;
 using TakeoutSaaS.Domain.Identity.Repositories;
 using TakeoutSaaS.Infrastructure.Identity.Persistence;
-using TakeoutSaaS.Shared.Abstractions.Tenancy;
 
 namespace TakeoutSaaS.Infrastructure.Identity.Repositories;
 
 /// <summary>
 /// 菜单仓储 EF 实现。
 /// </summary>
-public sealed class EfMenuRepository(IdentityDbContext dbContext, ITenantContextAccessor tenantContextAccessor) : IMenuRepository
+public sealed class EfMenuRepository(IdentityDbContext dbContext) : IMenuRepository
 {
     /// <inheritdoc />
     public async Task<IReadOnlyList<MenuDefinition>> GetByTenantAsync(long tenantId, CancellationToken cancellationToken = default)
     {
-        // 1. 优先返回租户自定义菜单
+        // 1. 仅返回该租户的菜单，无回退逻辑
         var tenantMenus = await dbContext.MenuDefinitions
             .AsNoTracking()
-            .Where(x => x.TenantId == tenantId)
+            .Where(x => x.TenantId == tenantId && x.DeletedAt == null)
             .OrderBy(x => x.ParentId)
             .ThenBy(x => x.SortOrder)
             .ToListAsync(cancellationToken);
-        if (tenantMenus.Count > 0)
-        {
-            return tenantMenus;
-        }
 
-        // 2. (空行后) 回退系统默认菜单（TenantId=0）
+        return tenantMenus;
-        using (tenantContextAccessor.EnterTenantScope(0, "menu"))
-        {
-            var systemMenus = await dbContext.MenuDefinitions
-                .AsNoTracking()
-                .Where(x => x.TenantId == 0 && x.DeletedAt == null)
-                .OrderBy(x => x.ParentId)
-                .ThenBy(x => x.SortOrder)
-                .ToListAsync(cancellationToken);
-
-            return systemMenus;
-        }
     }
 
     /// <inheritdoc />
     public async Task<MenuDefinition?> FindByIdAsync(long id, long tenantId, CancellationToken cancellationToken = default)
     {
-        // 1. 优先查租户菜单
+        // 1. 仅查询该租户的菜单，无回退逻辑
-        var tenantMenu = await dbContext.MenuDefinitions
+        return await dbContext.MenuDefinitions
             .AsNoTracking()
             .FirstOrDefaultAsync(
-                x => x.Id == id && x.TenantId == tenantId,
+                x => x.Id == id && x.TenantId == tenantId && x.DeletedAt == null,
                 cancellationToken);
-        if (tenantMenu != null)
-        {
-            return tenantMenu;
-        }
-
-        // 2. (空行后) 回退查系统默认菜单（TenantId=0）
-        using (tenantContextAccessor.EnterTenantScope(0, "menu"))
-        {
-            return await dbContext.MenuDefinitions
-                .AsNoTracking()
-                .FirstOrDefaultAsync(x => x.Id == id && x.TenantId == 0 && x.DeletedAt == null, cancellationToken);
-        }
     }
 
     /// <inheritdoc />

src/Modules/TakeoutSaaS.Module.Tenancy/DatabaseTenantCodeResolver.cs

@@ -0,0 +1,22 @@
+using TakeoutSaaS.Domain.Tenants.Repositories;
+
+namespace TakeoutSaaS.Module.Tenancy;
+
+/// <summary>
+/// 基于数据库的租户编码解析器实现。
+/// </summary>
+public sealed class DatabaseTenantCodeResolver(ITenantRepository tenantRepository) : ITenantCodeResolver
+{
+    /// <inheritdoc />
+    public Task<long?> ResolveAsync(string code, CancellationToken cancellationToken = default)
+    {
+        // 1. 参数校验
+        if (string.IsNullOrWhiteSpace(code))
+        {
+            return Task.FromResult<long?>(null);
+        }
+
+        // 2. 从数据库查询租户 ID
+        return tenantRepository.FindIdByCodeAsync(code, cancellationToken);
+    }
+}

src/Modules/TakeoutSaaS.Module.Tenancy/Extensions/TenantServiceCollectionExtensions.cs

@@ -18,6 +18,7 @@ public static class TenantServiceCollectionExtensions
     {
         services.TryAddSingleton<ITenantContextAccessor, TenantContextAccessor>();
         services.TryAddScoped<ITenantProvider, TenantProvider>();
+        services.TryAddScoped<ITenantCodeResolver, DatabaseTenantCodeResolver>();
 
         services.AddOptions<TenantResolutionOptions>()
             .Bind(configuration.GetSection("Tenancy"))

src/Modules/TakeoutSaaS.Module.Tenancy/ITenantCodeResolver.cs

@@ -0,0 +1,15 @@
+namespace TakeoutSaaS.Module.Tenancy;
+
+/// <summary>
+/// 租户编码解析器：根据租户编码查询租户 ID。
+/// </summary>
+public interface ITenantCodeResolver
+{
+    /// <summary>
+    /// 根据租户编码查询租户 ID。
+    /// </summary>
+    /// <param name="code">租户编码。</param>
+    /// <param name="cancellationToken">取消令牌。</param>
+    /// <returns>租户 ID，未找到返回 null。</returns>
+    Task<long?> ResolveAsync(string code, CancellationToken cancellationToken = default);
+}

src/Modules/TakeoutSaaS.Module.Tenancy/TakeoutSaaS.Module.Tenancy.csproj

@@ -6,6 +6,7 @@
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\..\TakeoutSaaS.BuildingBlocks\src\Core\TakeoutSaaS.Shared.Abstractions\TakeoutSaaS.Shared.Abstractions.csproj" />
+    <ProjectReference Include="..\..\Domain\TakeoutSaaS.Domain\TakeoutSaaS.Domain.csproj" />
   </ItemGroup>
   <ItemGroup>
     <FrameworkReference Include="Microsoft.AspNetCore.App" />

src/Modules/TakeoutSaaS.Module.Tenancy/TenantResolutionMiddleware.cs

@@ -22,7 +22,7 @@ public sealed class TenantResolutionMiddleware(
     /// <summary>
     /// 解析租户并将上下文注入请求。
     /// </summary>
-    public async Task InvokeAsync(HttpContext context)
+    public async Task InvokeAsync(HttpContext context, ITenantCodeResolver tenantCodeResolver)
     {
         var options = optionsMonitor.CurrentValue ?? new TenantResolutionOptions();
         if (ShouldSkip(context.Request.Path, options))
@@ -31,7 +31,7 @@ public sealed class TenantResolutionMiddleware(
             return;
         }
 
-        var tenantContext = ResolveTenant(context, options);
+        var tenantContext = await ResolveTenantAsync(context, options, tenantCodeResolver);
         tenantContextAccessor.Current = tenantContext;
         context.Items[TenantConstants.HttpContextItemKey] = tenantContext;
 
@@ -86,7 +86,10 @@ public sealed class TenantResolutionMiddleware(
         });
     }
 
-    private static TenantContext ResolveTenant(HttpContext context, TenantResolutionOptions options)
+    private static async Task<TenantContext> ResolveTenantAsync(
+        HttpContext context,
+        TenantResolutionOptions options,
+        ITenantCodeResolver tenantCodeResolver)
     {
         var request = context.Request;
         var isAuthenticated = context.User?.Identity?.IsAuthenticated == true;
@@ -117,9 +120,10 @@ public sealed class TenantResolutionMiddleware(
             request.Headers.TryGetValue(options.TenantCodeHeaderName, out var codeHeader))
         {
             var code = codeHeader.FirstOrDefault();
-            if (TryResolveByCode(code, options, out var tenantFromCode))
+            var tenantFromCode = await ResolveByCodeAsync(code, options, tenantCodeResolver, context.RequestAborted);
+            if (tenantFromCode.HasValue)
             {
-                return new TenantContext(tenantFromCode, code, $"header:{options.TenantCodeHeaderName}");
+                return new TenantContext(tenantFromCode.Value, code, $"header:{options.TenantCodeHeaderName}");
             }
         }
 
@@ -127,30 +131,43 @@ public sealed class TenantResolutionMiddleware(
         var host = request.Host.Host;
         if (!string.IsNullOrWhiteSpace(host))
         {
+            // 4.1 精确域名映射
             if (options.DomainTenantMap.TryGetValue(host, out var tenantFromHost) && tenantFromHost > 0)
             {
                 return new TenantContext(tenantFromHost, null, $"host:{host}");
             }
 
+            // 4.2 子域名解析
             var codeFromHost = ResolveCodeFromHost(host, options.RootDomain);
-            if (TryResolveByCode(codeFromHost, options, out var tenantFromSubdomain))
+            var tenantFromSubdomain = await ResolveByCodeAsync(codeFromHost, options, tenantCodeResolver, context.RequestAborted);
+            if (tenantFromSubdomain.HasValue)
             {
-                return new TenantContext(tenantFromSubdomain, codeFromHost, $"host:{host}");
+                return new TenantContext(tenantFromSubdomain.Value, codeFromHost, $"host:{host}");
             }
         }
 
         return TenantContext.Empty;
     }
 
-    private static bool TryResolveByCode(string? code, TenantResolutionOptions options, out long tenantId)
+    private static async Task<long?> ResolveByCodeAsync(
+        string? code,
+        TenantResolutionOptions options,
+        ITenantCodeResolver tenantCodeResolver,
+        CancellationToken cancellationToken)
     {
-        tenantId = 0;
         if (string.IsNullOrWhiteSpace(code))
         {
-            return false;
+            return null;
         }
 
-        return options.CodeTenantMap.TryGetValue(code, out tenantId) && tenantId > 0;
+        // 1. 优先从静态配置查找（兼容旧配置）
+        if (options.CodeTenantMap.TryGetValue(code, out var tenantId) && tenantId > 0)
+        {
+            return tenantId;
+        }
+
+        // 2. 从数据库动态查询
+        return await tenantCodeResolver.ResolveAsync(code, cancellationToken);
     }
 
     private static string? ResolveCodeFromHost(string host, string? rootDomain)