| name | bwfc-identity-migration |
| description | **WORKFLOW SKILL** — Migrate ASP.NET Web Forms Identity and Membership authentication to Blazor Server Identity. Covers OWIN→Core middleware, login/register/logout minimal API endpoints, BWFC login controls, cookie auth under Interactive Server, and role-based authorization. WHEN: "migrate identity", "login page migration", "OWIN to core", "cookie auth blazor", "LoginView migration". INVOKES: dotnet CLI for identity scaffolding. FOR SINGLE OPERATIONS: use bwfc-migration for markup, bwfc-data-migration for EF. |
Web Forms Identity → Blazor Identity Migration
Overview
| Web Forms Auth System | Era | Blazor Migration Path |
|---|
| ASP.NET Identity (OWIN) | 2013+ | ASP.NET Core Identity (closest match) |
| ASP.NET Membership | 2005-2013 | Core Identity (schema migration required) |
| FormsAuthentication | 2002-2005 | Core Identity or cookie auth |
Related: /bwfc-migration (markup), /bwfc-data-migration (EF/architecture)
Critical Rules
- Cookie auth requires HTTP endpoints — login/register/logout MUST use
<form method="post"> + minimal API endpoints. Component event handlers (@onclick) silently fail for cookie operations in interactive mode.
- NEVER replace LoginView with AuthorizeView — BWFC
LoginView uses AuthenticationStateProvider natively with same template names (AnonymousTemplate, LoggedInTemplate).
- DisableAntiforgery required — Blazor forms don't include antiforgery tokens. All auth endpoints must call
.DisableAntiforgery().
- Session-based auth data works —
Session["key"] via WebFormsPageBase.Session / SessionShim. Don't inject IHttpContextAccessor.
Quick Reference
BWFC Login Controls (drop-in replacements)
<Login />, <LoginName />, <LoginStatus />, <LoginView>, <CreateUserWizard />, <ChangePassword />, <PasswordRecovery />
Auth Endpoint Pattern
app.MapPost("/Account/LoginHandler", async (HttpContext ctx, SignInManager<IdentityUser> sm) =>
{
var form = await ctx.Request.ReadFormAsync();
var result = await sm.PasswordSignInAsync(form["email"]!, form["password"]!, false, false);
return result.Succeeded ? Results.Redirect("/") : Results.Redirect("/Account/Login?error=failed");
}).DisableAntiforgery();
Companion Documents
| Document | Content |
|---|
| IDENTITY-PATTERNS.md | Cookie auth details, identity config steps, BWFC login controls, authorization patterns, endpoint templates, OWIN mapping, gotchas |
L2 Break-Fix Playbook
Step 1: Add Identity Packages
dotnet add package Microsoft.AspNetCore.Identity.EntityFrameworkCore
dotnet add package Microsoft.AspNetCore.Identity.UI
Step 2: Configure Identity in Program.cs
builder.Services.AddIdentity<ApplicationUser, IdentityRole>(options =>
{
options.SignIn.RequireConfirmedAccount = false;
options.Password.RequiredLength = 6;
})
.AddEntityFrameworkStores<ApplicationDbContext>()
.AddDefaultTokenProviders();
builder.Services.AddCascadingAuthenticationState();
app.UseAuthentication();
app.UseAuthorization();
Step 3: Create ApplicationUser and DbContext
using Microsoft.AspNetCore.Identity;
public class ApplicationUser : IdentityUser
{
}
using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore;
public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
{
public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
: base(options) { }
}
Step 4: Migrate the Database Schema
If migrating from ASP.NET Identity (OWIN), the schema is similar but not identical:
dotnet ef migrations add IdentityMigration
dotnet ef database update
Key schema differences:
| ASP.NET Identity (OWIN) | ASP.NET Core Identity |
|---|
AspNetUsers.Id (string GUID) | Same |
AspNetUsers.PasswordHash | Same format — passwords are compatible |
AspNetUserClaims | Same |
AspNetUserRoles | Same |
AspNetRoles | Same |
__MigrationHistory | __EFMigrationsHistory |
Important: ASP.NET Identity v2 password hashes (from Web Forms) are compatible with ASP.NET Core Identity. Users will NOT need to reset passwords.
If migrating from Membership (older):
- Use the
Microsoft.AspNetCore.Identity.MicrosoftAccountMigration or a custom SQL migration script
- Membership password hashes are NOT compatible — users will need password resets
Step 5: Migrate Login Pages
BWFC Login Controls
BWFC provides login controls that match Web Forms markup. These controls use native Blazor AuthenticationStateProvider internally — they are not shims and do not need to be replaced with AuthorizeView.
Important: BWFC login controls require builder.Services.AddBlazorWebFormsComponents() in Program.cs and builder.Services.AddCascadingAuthenticationState() for authentication state propagation.
| Web Forms | BWFC | Notes |
|---|
<asp:Login runat="server" /> | <Login /> | Login form with username/password |
<asp:LoginName runat="server" /> | <LoginName /> | Displays authenticated username |
<asp:LoginStatus runat="server" /> | <LoginStatus /> | Login/Logout toggle link |
<asp:LoginView runat="server"> | <LoginView> | Shows different content for anon vs auth users |
<asp:CreateUserWizard runat="server" /> | <CreateUserWizard /> | Registration form |
<asp:ChangePassword runat="server" /> | <ChangePassword /> | Password change form |
<asp:PasswordRecovery runat="server" /> | <PasswordRecovery /> | Password reset flow |
Login Page Migration Example
<%@ Page Title="Log in" MasterPageFile="~/Site.Master" ... %>
<asp:Content ContentPlaceHolderID="MainContent" runat="server">
<h2>Log in</h2>
<asp:Login ID="LoginCtrl" runat="server"
ViewStateMode="Disabled"
RenderOuterTable="false">
<LayoutTemplate>
<asp:TextBox ID="UserName" runat="server" CssClass="form-control" />
<asp:RequiredFieldValidator ControlToValidate="UserName"
ErrorMessage="Required" runat="server" />
<asp:TextBox ID="Password" TextMode="Password" runat="server" />
<asp:Button Text="Log in" CommandName="Login" runat="server" />
</LayoutTemplate>
</asp:Login>
</asp:Content>
@* Blazor — Login.razor *@
@page "/Account/Login"
<h2>Log in</h2>
<Login RenderOuterTable="false">
<LayoutTemplate>
<TextBox @bind-Text="model.UserName" CssClass="form-control" />
<RequiredFieldValidator ControlToValidate="UserName" ErrorMessage="Required" />
<TextBox TextMode="Password" @bind-Text="model.Password" />
<Button Text="Log in" CommandName="Login" />
</LayoutTemplate>
</Login>
Step 6: Migrate Authorization Patterns
Web.config Authorization → Blazor Authorization
<location path="Admin">
<system.web>
<authorization>
<allow roles="Administrator" />
<deny users="*" />
</authorization>
</system.web>
</location>
@* Blazor — Admin pages use [Authorize] attribute *@
@page "/Admin"
@attribute [Authorize(Roles = "Administrator")]
<h1>Admin Panel</h1>
LoginView Conditional Content
<asp:LoginView runat="server">
<AnonymousTemplate>
<a href="~/Account/Login">Log in</a>
</AnonymousTemplate>
<LoggedInTemplate>
Welcome, <asp:LoginName runat="server" />!
<asp:LoginStatus runat="server" LogoutAction="Redirect" LogoutPageUrl="~/" />
</LoggedInTemplate>
</asp:LoginView>
@* Blazor — BWFC LoginView (recommended — preserves markup and uses AuthenticationStateProvider natively) *@
<LoginView>
<AnonymousTemplate>
<a href="/Account/Login">Log in</a>
</AnonymousTemplate>
<LoggedInTemplate>
Welcome, <LoginName />!
<LoginStatus LogoutAction="Redirect" LogoutPageUrl="/" />
</LoggedInTemplate>
</LoginView>
Note: BWFC's LoginView internally injects AuthenticationStateProvider and evaluates authentication state natively — it is NOT a shim that needs to be replaced. Keep it for markup compatibility. If you prefer native Blazor syntax long-term:
@* Blazor — Native AuthorizeView (alternative — different template names) *@
<AuthorizeView>
<NotAuthorized>
<a href="/Account/Login">Log in</a>
</NotAuthorized>
<Authorized>
Welcome, @context.User.Identity?.Name!
<a href="/Account/Logout">Log out</a>
</Authorized>
</AuthorizeView>
⚠️ NEVER replace LoginView with AuthorizeView. The BWFC LoginView component is a fully functional Blazor component that injects AuthenticationStateProvider natively. It uses the SAME template names as asp:LoginView (AnonymousTemplate, LoggedInTemplate). The migration script handles this automatically — do NOT convert to AuthorizeView manually. Use AuthorizeView only when you need Blazor-native role-based content (<AuthorizeView Roles="...">) with no Web Forms equivalent.
Role-Based Content
<asp:LoginView runat="server">
<RoleGroups>
<asp:RoleGroup Roles="Administrator">
<ContentTemplate><a href="~/Admin">Admin Panel</a></ContentTemplate>
</asp:RoleGroup>
</RoleGroups>
</asp:LoginView>
@* Blazor *@
<AuthorizeView Roles="Administrator">
<a href="/Admin">Admin Panel</a>
</AuthorizeView>
Step 7: Migrate Authentication State Access
Code-Behind Auth Patterns
if (HttpContext.Current.User.Identity.IsAuthenticated)
{
var userName = HttpContext.Current.User.Identity.Name;
var isAdmin = HttpContext.Current.User.IsInRole("Administrator");
}
var manager = Context.GetOwinContext().GetUserManager<ApplicationUserManager>();
var user = manager.FindById(User.Identity.GetUserId());
@inject AuthenticationStateProvider AuthStateProvider
@code {
private string? userName;
private bool isAdmin;
protected override async Task OnInitializedAsync()
{
var authState = await AuthStateProvider.GetAuthenticationStateAsync();
var user = authState.User;
userName = user.Identity?.Name;
isAdmin = user.IsInRole("Administrator");
}
}
Cascading Auth Parameter (Simpler)
[CascadingParameter]
private Task<AuthenticationState>? AuthState { get; set; }
protected override async Task OnInitializedAsync()
{
if (AuthState != null)
{
var state = await AuthState;
var user = state.User;
}
}
Session-Based Auth Data
Note: WebFormsPageBase provides a Session property (via SessionShim) that works in Blazor Server interactive mode. If your Web Forms code stores auth-related data in session (e.g., Session["userCheckoutCompleted"], Session["token"], Session["cartId"]), you can access it the same way in migrated Blazor code:
Session["userCheckoutCompleted"] = true;
if (Session["token"] is string token) { ... }
Session["userCheckoutCompleted"] = true;
if (Session["token"] is string token) { ... }
SessionShim uses IHttpContextAccessor and ISession under the hood, but you should not inject IHttpContextAccessor directly when WebFormsPageBase.Session already provides the same access pattern. Keep the shim-based approach during initial migration — session-to-DI conversion is an optional L3 optimization step, not a Layer 1 or Layer 2 requirement.
OWIN Middleware → ASP.NET Core Middleware
| Web Forms (OWIN Startup.cs) | Blazor (Program.cs) |
|---|
app.UseCookieAuthentication(...) | builder.Services.AddAuthentication().AddCookie(...) |
app.UseExternalSignInCookie(...) | builder.Services.AddAuthentication().AddGoogle/Facebook(...) |
ConfigureAuth(app) in Startup.Auth.cs | Configuration in Program.cs services section |
app.CreatePerOwinContext<ApplicationUserManager>(...) | builder.Services.AddIdentity<ApplicationUser, IdentityRole>() |
SecurityStampValidator.OnValidateIdentity(...) | Built into ASP.NET Core Identity automatically |
Ready-to-Use Endpoint Templates
These minimal API endpoints handle authentication operations that must run over HTTP (not WebSocket). Add them to Program.cs after building the app but before app.Run(). Each endpoint reads form data, performs the auth operation, and redirects back to a Blazor page.
Important: Every endpoint below calls .DisableAntiforgery() because Blazor-rendered <form> elements do not include antiforgery tokens. See DisableAntiforgery Requirement.
Login Endpoint
app.MapPost("/Account/LoginHandler", async (HttpContext context, SignInManager<IdentityUser> signInManager) =>
{
var form = await context.Request.ReadFormAsync();
var email = form["email"].ToString();
var password = form["password"].ToString();
var result = await signInManager.PasswordSignInAsync(email, password, isPersistent: false, lockoutOnFailure: false);
if (result.Succeeded)
return Results.Redirect("/");
return Results.Redirect("/Account/Login?error=Invalid+login+attempt");
}).DisableAntiforgery();
Blazor form that submits to this endpoint:
@page "/Account/Login"
<h2>Log in</h2>
@if (!string.IsNullOrEmpty(errorMessage))
{
<div class="text-danger">@errorMessage</div>
}
<form method="post" action="/Account/LoginHandler">
<div>
<label>Email</label>
<input type="email" name="email" required />
</div>
<div>
<label>Password</label>
<input type="password" name="password" required />
</div>
<button type="submit">Log in</button>
</form>
@code {
[SupplyParameterFromQuery] public string? Error { get; set; }
private string? errorMessage;
protected override void OnInitialized()
{
errorMessage = Error;
}
}
Register Endpoint
app.MapPost("/Account/RegisterHandler", async (HttpContext context,
UserManager<IdentityUser> userManager, SignInManager<IdentityUser> signInManager) =>
{
var form = await context.Request.ReadFormAsync();
var email = form["email"].ToString();
var password = form["password"].ToString();
var user = new IdentityUser { UserName = email, Email = email };
var result = await userManager.CreateAsync(user, password);
if (result.Succeeded)
{
await signInManager.SignInAsync(user, isPersistent: false);
return Results.Redirect("/");
}
var errors = string.Join("; ", result.Errors.Select(e => e.Description));
return Results.Redirect($"/Account/Register?error={Uri.EscapeDataString(errors)}");
}).DisableAntiforgery();
Logout Endpoint
app.MapPost("/Account/Logout", async (SignInManager<IdentityUser> signInManager) =>
{
await signInManager.SignOutAsync();
return Results.Redirect("/");
}).DisableAntiforgery();
Blazor logout form (use instead of a link):
<form method="post" action="/Account/Logout">
<button type="submit" class="nav-link btn btn-link">Log out</button>
</form>
Note: Do NOT use <a href="/Account/Logout"> — Blazor's enhanced navigation will intercept the click and attempt client-side navigation instead of a real HTTP POST. Use a <form method="post"> with a submit button, or add data-enhance-nav="false" to the link. See Blazor Enhanced Navigation in the data migration skill.
DisableAntiforgery Requirement
Important: When using <form method="post"> to submit to minimal API endpoints from Blazor-rendered pages, the endpoint MUST call .DisableAntiforgery() because Blazor's HTML rendering does not include antiforgery tokens. Without this, the request will fail with a 400 Bad Request.
app.MapPost("/Account/LoginHandler", handler).DisableAntiforgery();
app.MapPost("/Account/LoginHandler", handler);
If you need antiforgery protection, you must manually include the token in the form using @inject Microsoft.AspNetCore.Antiforgery.IAntiforgery and render a hidden field. For most migration scenarios, .DisableAntiforgery() is the pragmatic choice.
Common Identity Gotchas
No HttpContext.Current
Blazor Server has no HttpContext.Current. Use dependency injection:
Cookie Auth Requires HTTP Endpoints
Blazor Server login/logout MUST use HTTP endpoints (not component-based), because cookies are set on HTTP responses:
app.MapPost("/Account/Logout", async (SignInManager<ApplicationUser> signInManager) =>
{
await signInManager.SignOutAsync();
return Results.Redirect("/");
});
SignalR Circuit vs HTTP Request
Authentication state is captured when the circuit starts. If the user's session expires mid-circuit, they remain "authenticated" until the page refreshes. Use RevalidatingServerAuthenticationStateProvider for periodic revalidation.
Blazor Identity UI Scaffolding
For a complete Identity UI (login, register, manage profile), scaffold it:
dotnet aspnet-codegenerator identity -dc ApplicationDbContext --files "Account.Login;Account.Register;Account.Logout"
This generates Razor Pages (not components) under /Areas/Identity/. They coexist with Blazor.