refactor(identity): split UserService into single-responsibility services (#1174) (#1192)

Split the UserService god class into focused, single-responsibility services:

**New Interfaces (Modules.Identity.Contracts/Services/):**
- IUserRegistrationService: User registration and external auth
- IUserProfileService: Profile CRUD operations
- IUserStatusService: Status toggle and delete operations
- IUserRoleService: Role assignment operations
- IUserPasswordService: Password operations (forgot/reset/change)
- IUserPermissionService: Permission queries and caching

**New Implementations (Modules.Identity/Services/):**
- UserRegistrationService
- UserProfileService
- UserStatusService
- UserRoleService
- UserPasswordService
- UserPermissionService

**Other Changes:**
- UserService now acts as a facade delegating to the new services
- Updated DI registration in IdentityModule.cs
- Deleted 7 old partial class files

This improves:
- Single Responsibility Principle compliance
- Testability (smaller focused services)
- Maintainability (clear separation of concerns)
- Reusability (handlers can inject specific services they need)

Closes #1174

Co-authored-by: jarvis <jarvis@codewithmukesh.com>

Author: iammukeshm

src/Modules/Identity/Modules.Identity.Contracts/Services/IUserPasswordService.cs

@@ -0,0 +1,22 @@
+namespace FSH.Modules.Identity.Contracts.Services;
+
+/// <summary>
+/// Service for user password operations.
+/// </summary>
+public interface IUserPasswordService
+{
+    /// <summary>
+    /// Initiates the forgot password flow by sending a reset email.
+    /// </summary>
+    Task ForgotPasswordAsync(string email, string origin, CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Resets a user's password using a token.
+    /// </summary>
+    Task ResetPasswordAsync(string email, string password, string token, CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Changes the current user's password.
+    /// </summary>
+    Task ChangePasswordAsync(string password, string newPassword, string confirmNewPassword, string userId);
+}

src/Modules/Identity/Modules.Identity.Contracts/Services/IUserPermissionService.cs

@@ -0,0 +1,22 @@
+namespace FSH.Modules.Identity.Contracts.Services;
+
+/// <summary>
+/// Service for user permission operations.
+/// </summary>
+public interface IUserPermissionService
+{
+    /// <summary>
+    /// Gets all permissions for a user.
+    /// </summary>
+    Task<List<string>?> GetPermissionsAsync(string userId, CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Checks if a user has a specific permission.
+    /// </summary>
+    Task<bool> HasPermissionAsync(string userId, string permission, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Invalidates the permission cache for a user.
+    /// </summary>
+    Task InvalidatePermissionCacheAsync(string userId, CancellationToken cancellationToken);
+}

src/Modules/Identity/Modules.Identity.Contracts/Services/IUserProfileService.cs

@@ -0,0 +1,45 @@
+using FSH.Framework.Shared.Storage;
+using FSH.Modules.Identity.Contracts.DTOs;
+
+namespace FSH.Modules.Identity.Contracts.Services;
+
+/// <summary>
+/// Service for user profile operations.
+/// </summary>
+public interface IUserProfileService
+{
+    /// <summary>
+    /// Gets a user by ID.
+    /// </summary>
+    Task<UserDto> GetAsync(string userId, CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Gets all users.
+    /// </summary>
+    Task<List<UserDto>> GetListAsync(CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Gets the total user count.
+    /// </summary>
+    Task<int> GetCountAsync(CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Updates a user's profile.
+    /// </summary>
+    Task UpdateAsync(string userId, string firstName, string lastName, string phoneNumber, FileUploadRequest image, bool deleteCurrentImage);
+
+    /// <summary>
+    /// Checks if a user exists with the given email.
+    /// </summary>
+    Task<bool> ExistsWithEmailAsync(string email, string? exceptId = null);
+
+    /// <summary>
+    /// Checks if a user exists with the given username.
+    /// </summary>
+    Task<bool> ExistsWithNameAsync(string name);
+
+    /// <summary>
+    /// Checks if a user exists with the given phone number.
+    /// </summary>
+    Task<bool> ExistsWithPhoneNumberAsync(string phoneNumber, string? exceptId = null);
+}

src/Modules/Identity/Modules.Identity.Contracts/Services/IUserRegistrationService.cs

@@ -0,0 +1,38 @@
+using System.Security.Claims;
+
+namespace FSH.Modules.Identity.Contracts.Services;
+
+/// <summary>
+/// Service for user registration and external authentication.
+/// </summary>
+public interface IUserRegistrationService
+{
+    /// <summary>
+    /// Registers a new user with password.
+    /// </summary>
+    Task<string> RegisterAsync(
+        string firstName,
+        string lastName,
+        string email,
+        string userName,
+        string password,
+        string confirmPassword,
+        string phoneNumber,
+        string origin,
+        CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Gets or creates a user from an external authentication principal.
+    /// </summary>
+    Task<string> GetOrCreateFromPrincipalAsync(ClaimsPrincipal principal);
+
+    /// <summary>
+    /// Confirms a user's email address.
+    /// </summary>
+    Task<string> ConfirmEmailAsync(string userId, string code, string tenant, CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Confirms a user's phone number.
+    /// </summary>
+    Task<string> ConfirmPhoneNumberAsync(string userId, string code);
+}

src/Modules/Identity/Modules.Identity.Contracts/Services/IUserRoleService.cs

@@ -0,0 +1,19 @@
+using FSH.Modules.Identity.Contracts.DTOs;
+
+namespace FSH.Modules.Identity.Contracts.Services;
+
+/// <summary>
+/// Service for user role management.
+/// </summary>
+public interface IUserRoleService
+{
+    /// <summary>
+    /// Assigns roles to a user.
+    /// </summary>
+    Task<string> AssignRolesAsync(string userId, List<UserRoleDto> userRoles, CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Gets all roles for a user.
+    /// </summary>
+    Task<List<UserRoleDto>> GetUserRolesAsync(string userId, CancellationToken cancellationToken);
+}

src/Modules/Identity/Modules.Identity.Contracts/Services/IUserStatusService.cs

@@ -0,0 +1,17 @@
+namespace FSH.Modules.Identity.Contracts.Services;
+
+/// <summary>
+/// Service for user status and lifecycle operations.
+/// </summary>
+public interface IUserStatusService
+{
+    /// <summary>
+    /// Toggles a user's active status.
+    /// </summary>
+    Task ToggleStatusAsync(bool activateUser, string userId, CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Soft-deletes a user by deactivating them.
+    /// </summary>
+    Task DeleteAsync(string userId);
+}

src/Modules/Identity/Modules.Identity/IdentityModule.cs

@@ -77,7 +77,18 @@ public void ConfigureServices(IHostApplicationBuilder builder)
         services.AddScoped<IRequestContext, RequestContextService>();
         services.AddScoped<ITokenService, TokenService>();
         services.AddScoped(sp => (ICurrentUserInitializer)sp.GetRequiredService<ICurrentUser>());
+
+        // User services - focused single-responsibility services
+        services.AddTransient<IUserRegistrationService, UserRegistrationService>();
+        services.AddTransient<IUserProfileService, UserProfileService>();
+        services.AddTransient<IUserStatusService, UserStatusService>();
+        services.AddTransient<IUserRoleService, UserRoleService>();
+        services.AddTransient<IUserPasswordService, UserPasswordService>();
+        services.AddTransient<IUserPermissionService, UserPermissionService>();
+
+        // Facade for backward compatibility
         services.AddTransient<IUserService, UserService>();
+
         services.AddTransient<IRoleService, RoleService>();
         services.AddHeroStorage(builder.Configuration);
         services.AddScoped<IIdentityService, IdentityService>();

…dentity/Services/UserService.Password.cs …Identity/Services/UserPasswordService.cssrc/Modules/Identity/Modules.Identity/Services/UserService.Password.cs renamed to src/Modules/Identity/Modules.Identity/Services/UserPasswordService.cs src/Modules/Identity/Modules.Identity/Services/UserService.Password.cs renamed to src/Modules/Identity/Modules.Identity/Services/UserPasswordService.cs

@@ -1,12 +1,27 @@
-using FSH.Framework.Core.Exceptions;
+using Finbuckle.MultiTenant.Abstractions;
+using FSH.Framework.Core.Exceptions;
+using FSH.Framework.Jobs.Services;
 using FSH.Framework.Mailing;
+using FSH.Framework.Mailing.Services;
+using FSH.Framework.Shared.Multitenancy;
+using FSH.Modules.Identity.Contracts.Services;
+using FSH.Modules.Identity.Data;
+using FSH.Modules.Identity.Domain;
+using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.WebUtilities;
 using System.Collections.ObjectModel;
 using System.Text;
 
 namespace FSH.Modules.Identity.Services;
 
-internal sealed partial class UserService
+internal sealed class UserPasswordService(
+    UserManager<FshUser> userManager,
+    IdentityDbContext db,
+    IJobService jobService,
+    IMailService mailService,
+    IMultiTenantContextAccessor<AppTenantInfo> multiTenantContextAccessor,
+    IPasswordHistoryService passwordHistoryService,
+    IPasswordExpiryService passwordExpiryService) : IUserPasswordService
 {
     public async Task ForgotPasswordAsync(string email, string origin, CancellationToken cancellationToken)
     {
@@ -80,9 +95,17 @@ public async Task ChangePasswordAsync(string password, string newPassword, strin
         await db.SaveChangesAsync();
 
         // Update password expiry date
-        await _passwordExpiryService.UpdateLastPasswordChangeDateAsync(userId);
+        await passwordExpiryService.UpdateLastPasswordChangeDateAsync(userId);
 
         // Save to history
-        await _passwordHistoryService.SavePasswordHistoryAsync(userId);
+        await passwordHistoryService.SavePasswordHistoryAsync(userId);
     }
-}
+
+    private void EnsureValidTenant()
+    {
+        if (string.IsNullOrWhiteSpace(multiTenantContextAccessor?.MultiTenantContext?.TenantInfo?.Id))
+        {
+            throw new UnauthorizedException("invalid tenant");
+        }
+    }
+}

…tity/Services/UserService.Permissions.cs …entity/Services/UserPermissionService.cssrc/Modules/Identity/Modules.Identity/Services/UserService.Permissions.cs renamed to src/Modules/Identity/Modules.Identity/Services/UserPermissionService.cs src/Modules/Identity/Modules.Identity/Services/UserService.Permissions.cs renamed to src/Modules/Identity/Modules.Identity/Services/UserPermissionService.cs

@@ -1,11 +1,19 @@
-using FSH.Framework.Caching;
+using FSH.Framework.Caching;
 using FSH.Framework.Core.Exceptions;
 using FSH.Framework.Shared.Constants;
+using FSH.Modules.Identity.Contracts.Services;
+using FSH.Modules.Identity.Data;
+using FSH.Modules.Identity.Domain;
+using Microsoft.AspNetCore.Identity;
 using Microsoft.EntityFrameworkCore;
 
 namespace FSH.Modules.Identity.Services;
 
-internal sealed partial class UserService
+internal sealed class UserPermissionService(
+    UserManager<FshUser> userManager,
+    RoleManager<FshRole> roleManager,
+    IdentityDbContext db,
+    ICacheService cache) : IUserPermissionService
 {
     public async Task<List<string>?> GetPermissionsAsync(string userId, CancellationToken cancellationToken)
     {
@@ -51,4 +59,4 @@ public Task InvalidatePermissionCacheAsync(string userId, CancellationToken canc
     {
         return cache.RemoveItemAsync(GetPermissionCacheKey(userId), cancellationToken);
     }
-}
+}

…Identity/Services/UserService.Profile.cs ….Identity/Services/UserProfileService.cssrc/Modules/Identity/Modules.Identity/Services/UserService.Profile.cs renamed to src/Modules/Identity/Modules.Identity/Services/UserProfileService.cs src/Modules/Identity/Modules.Identity/Services/UserService.Profile.cs renamed to src/Modules/Identity/Modules.Identity/Services/UserProfileService.cs

@@ -1,14 +1,30 @@
+using Finbuckle.MultiTenant.Abstractions;
 using FSH.Framework.Core.Exceptions;
+using FSH.Framework.Shared.Multitenancy;
 using FSH.Framework.Shared.Storage;
 using FSH.Framework.Storage;
+using FSH.Framework.Storage.Services;
+using FSH.Framework.Web.Origin;
 using FSH.Modules.Identity.Contracts.DTOs;
+using FSH.Modules.Identity.Contracts.Services;
 using FSH.Modules.Identity.Domain;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Identity;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Options;
 
 namespace FSH.Modules.Identity.Services;
 
-internal sealed partial class UserService
+internal sealed class UserProfileService(
+    UserManager<FshUser> userManager,
+    SignInManager<FshUser> signInManager,
+    IStorageService storageService,
+    IMultiTenantContextAccessor<AppTenantInfo> multiTenantContextAccessor,
+    IOptions<OriginOptions> originOptions,
+    IHttpContextAccessor httpContextAccessor) : IUserProfileService
 {
+    private readonly Uri? _originUrl = originOptions.Value.OriginUrl;
+
     public async Task<UserDto> GetAsync(string userId, CancellationToken cancellationToken)
     {
         var user = await userManager.Users
@@ -105,4 +121,43 @@ public async Task<bool> ExistsWithPhoneNumberAsync(string phoneNumber, string? e
         EnsureValidTenant();
         return await userManager.Users.FirstOrDefaultAsync(x => x.PhoneNumber == phoneNumber) is FshUser user && user.Id != exceptId;
     }
+
+    private void EnsureValidTenant()
+    {
+        if (string.IsNullOrWhiteSpace(multiTenantContextAccessor?.MultiTenantContext?.TenantInfo?.Id))
+        {
+            throw new UnauthorizedException("invalid tenant");
+        }
+    }
+
+    private string? ResolveImageUrl(Uri? imageUrl)
+    {
+        if (imageUrl is null)
+        {
+            return null;
+        }
+
+        // Absolute URLs (e.g., S3) pass through unchanged.
+        if (imageUrl.IsAbsoluteUri)
+        {
+            return imageUrl.ToString();
+        }
+
+        // For relative paths from local storage, prefix with the API origin and wwwroot.
+        if (_originUrl is null)
+        {
+            var request = httpContextAccessor.HttpContext?.Request;
+            if (request is not null && !string.IsNullOrWhiteSpace(request.Scheme) && request.Host.HasValue)
+            {
+                var baseUri = $"{request.Scheme}://{request.Host.Value}{request.PathBase}";
+                var relativePath = imageUrl.ToString().TrimStart('/');
+                return $"{baseUri.TrimEnd('/')}/{relativePath}";
+            }
+
+            return imageUrl.ToString();
+        }
+
+        var originRelativePath = imageUrl.ToString().TrimStart('/');
+        return $"{_originUrl.AbsoluteUri.TrimEnd('/')}/{originRelativePath}";
+    }
 }