C# – ASP.NET Core Identity does not inject UserManager

asp.net-coreasp.net-core-mvcasp.net-identityasp.net-web-apic

I've got an older asp.net core identity database, and I want to map a new project (a web api) to it.

Just for the test, I copied the Models folder, and the ApplicationUser file from the previous project (ApplicationUser simply inherits from IdentityUser, no changes whatsoever) – doing DB first seems to be a bad idea.

I'm registering Identity in ConfigureServices (but I'm not adding it to the pipeline since my only intention is to use the UserStore)

        services.AddIdentity<ApplicationUser, IdentityRole>()
            .AddEntityFrameworkStores<ApplicationDbContext>()
            .AddDefaultTokenProviders();

My expectation is that now

     UserManager<ApplicationUser>

…should be automatically injected into constructors.

However, when adding the following code to a controller
private UserManager _userManager;

    public UserController(UserManager<ApplicationUser> userManager)
    {
        _userManager = userManager;
    }

… every call to the api ends with an exception:
HttpRequestException: Response status code does not indicate success: 500 (Internal Server Error).

Removing the "injection" code results in smoothly running web api that can accept requests.

It's hard to debug as this occurs before any of my code is reached. Any idea why this is occurring?

P.S. After enabling all exceptions from the Exception Settings window I got this one:

Exception thrown: 'System.InvalidOperationException' in
Microsoft.Extensions.DependencyInjection.dll

Additional information: Unable to resolve service for type
'Namespace.Data.ApplicationDbContext' while attempting to activate
'Microsoft.AspNetCore.Identity.EntityFrameworkCore.UserStore`4[Namespace.Models.
ApplicationUser,Microsoft.AspNetCore.Identity.EntityFrameworkCore.IdentityRole,Namespace.Data.ApplicationDbContext,System.String]'.

Best Answer

Do you have the app.UseIdentity(); call in the Configure method:

 public void Configure(IApplicationBuilder app, 
                       IHostingEnvironment env, ILoggerFactory loggerFactory)
    {
        /*...*/
        app.UseIdentity();
       /*...*/          
    }

EDIT Do you also have this line before the services.AddIdentity<ApplicationUser, IdentityRole>() line?

 public void ConfigureServices(IServiceCollection services)
 {
        // Add framework services.
        services.AddDbContext<ApplicationDbContext>(options =>
             options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));

 }

This should work OK. Also please check if ApplicationDbContext inherits from IdentityDbContext.

You should not need to query the database directly for the current ApplicationUser.

That introduces a new dependency of having an extra context for starters, but going forward the user database tables change (3 times in the past 2 years) but the API is consistent. For example the users table is now called AspNetUsers in Identity Framework, and the names of several primary key fields kept changing, so the code in several answers will no longer work as-is.

Another problem is that the underlying OWIN access to the database will use a separate context, so changes from separate SQL access can produce invalid results (e.g. not seeing changes made to the database). Again the solution is to work with the supplied API and not try to work-around it.

The correct way to access the current user object in ASP.Net identity (as at this date) is:

var user = UserManager.FindById(User.Identity.GetUserId());

or, if you have an async action, something like:

var user = await UserManager.FindByIdAsync(User.Identity.GetUserId());

FindById requires you have the following using statement so that the non-async UserManager methods are available (they are extension methods for UserManager, so if you do not include this you will only see FindByIdAsync):

using Microsoft.AspNet.Identity;

If you are not in a controller at all (e.g. you are using IOC injection), then the user id is retrieved in full from:

System.Web.HttpContext.Current.User.Identity.GetUserId();

If you are not in the standard Account controller you will need to add the following (as an example) to your controller:

1. Add these two properties:

    /// <summary>
    /// Application DB context
    /// </summary>
    protected ApplicationDbContext ApplicationDbContext { get; set; }

    /// <summary>
    /// User manager - attached to application DB context
    /// </summary>
    protected UserManager<ApplicationUser> UserManager { get; set; }

2. Add this in the Controller's constructor:

    this.ApplicationDbContext = new ApplicationDbContext();
    this.UserManager = new UserManager<ApplicationUser>(new UserStore<ApplicationUser>(this.ApplicationDbContext));

Update March 2015

Note: The most recent update to Identity framework changes one of the underlying classes used for authentication. You can now access it from the Owin Context of the current HttpContent.

ApplicationUser user = System.Web.HttpContext.Current.GetOwinContext().GetUserManager<ApplicationUserManager>().FindById(System.Web.HttpContext.Current.User.Identity.GetUserId());

Addendum:

When using EF and Identity Framework with Azure, over a remote database connection (e.g. local host testing to Azure database), you can randomly hit the dreaded “error: 19 - Physical connection is not usable”. As the cause is buried away inside Identity Framework, where you cannot add retries (or what appears to be a missing .Include(x->someTable)), you need to implement a custom SqlAzureExecutionStrategy in your project.

R – how to find keyboard in /dev on osx

OS X uses its own system to manage the PNP device tree, see http://developer.apple.com/mac/library/navigation/index.html?section=Topics&topic=Drivers%2C%20Kernel%2C%20%26amp%3B%20Hardware&kind=topic to get started

Best Answer

Related Solutions

C# – ASP.NET MVC 5 – Identity. How to get current ApplicationUser

You should not need to query the database directly for the current ApplicationUser.

1. Add these two properties:

2. Add this in the Controller's constructor:

Addendum:

R – how to find keyboard in /dev on osx

Related Topic