F# port of https://github.com/bumblebeeman/angularmvctutorial/blob/master/Part%20One/AwesomeAngularMVCApp/AwesomeAngularMVCApp/AwesomeAngularMVCApp/Controllers/AccountController.cs

AccountController.fsx

namespace AwesomeAngularMVCApp.Controllers

open System.Threading.Tasks
open System.Web
open System.Web.Mvc
open AwesomeAngularMVCApp.Models
open Microsoft.AspNet.Identity.Owin
open System.Web.Http.Owin

[<Authorize>]
type AccountController(userManager:ApplicationUserManager, signInManager:ApplicationSignInManager) =
    inherit Controller()

    // secondary constructor with implicit params
    new() = 
        let userManager = HttpContext.GetOwinContext().GetUserManager<ApplicationUserManager>()
        let signInManager = HttpContext.GetOwinContext().Get<ApplicationSignInManager>()
        new AccountController(userManager,signInManager)
        
    member this.UserManager = userManager
    member this.SignInManager = signInManager

    [<AllowAnonymous>]
    member this.Login() = this.View()
    
    [<AllowAnonymous>]
    member this.Register() = this.View()

    [<HttpPost>]
    [<AllowAnonymous>]
    member this.Login (model:LoginViewModel) =
        async {
            let! result = Async.AwaitTask <| signInManager.PasswordSignInAsync(model.Email, model.Password, model.RememberMe, false) 
            match result with 
                | SignInStatus.Success -> 
                    return true
                | _ ->
                    ModelState.AddModelError("", "Invalid login attempt.")
                    return false
            } |> Async.StartAsTask

    [<HttpPost>]
    [<AllowAnonymous>]
    member this.Register (model:RegisterViewModel) = 
        async {
            let user = ApplicationUser(UserName = model.Email, Email = model.Email)
            let! result = Async.AwaitTask <| userManager.CreateAsync(user, model.Password) 
            if not result.Succeeded then
                return false
            else
                do! Async.AwaitTask <| signInManager.SignInAsync(user, false, false) 
                return true
            } |> Async.StartAsTask

Models.fsx

namespace AwesomeAngularMVCApp.Models

open System.Web
open System.Web.Mvc
open System.ComponentModel.DataAnnotations

type LoginViewModel() = 
    [<Required>]
    [<Display(Name = "Email")>]
    [<EmailAddress>]
    member val Email :string = null

    [<Required>]
    [<DataType(DataType.Password)>]
    [<Display(Name = "Password")>]
    member val Password :string = null

    [<Display(Name = "Remember me?")>]
    member val RememberMe = false

type RegisterViewModel() = 
    [<Required>]
    [<EmailAddress>]
    [<Display(Name = "Email")>]
    member val Email :string = null

    [<Required>]
    [<StringLength(100, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 6)>]
    [<DataType(DataType.Password)>]
    [<Display(Name = "Password")>]
    member val Password :string = null

    [<DataType(DataType.Password)>]
    [<Display(Name = "Confirm password")>]
    [<Compare("Password", ErrorMessage = "The password and confirmation password do not match.")>]
    member val ConfirmPassword :string = null