Q:

How can I use the Reset Password Functionality in Web API 2

I have created a method so that when user requests for password reset, it sends an email to user. I want now to generate a url which opens ResetPassword.cshtml from web site to be opened. I am not able to hit website, because the web site page is asking for cookies which I do not have. 

A:

First generate an url for reset password page:
string code = await UserManager.GeneratePasswordResetTokenAsync(user.Id);
//For MVC controller
var callbackUrl = Url.Action("ResetPassword", "Account", new { code = code }, protocol: Request.Url.Scheme);
//For Web API controller
var callbackUrl = Url.Link("Default", new { Controller = "Account", Action = "ResetPassword", code = code });

After it create MVC controller with reset password method:
        [AllowAnonymous]
        public ActionResult ResetPassword(string code)
        {
            return code == null ? View("Error") : View();
        }

        [HttpPost]
        [AllowAnonymous]
        [ValidateAntiForgeryToken]
        public async Task<ActionResult> ResetPassword(ResetPasswordViewModel model)
        {
            if (!ModelState.IsValid)
            {
                return View(model);
            }
            var user = await UserManager.FindByNameAsync(model.Email);
            if (user == null)
            {
                // Don't reveal that the user does not exist
            }
            var result = await UserManager.ResetPasswordAsync(user.Id, model.Code, model.Password);
            if (result.Succeeded)
            {
                //...
            }
            AddErrors(result);
            return View();
        }

Then create the model to accept new password:
public class ResetPasswordViewModel
{
    [Required]
    [EmailAddress]
    [Display(Name = "Email")]
    public string Email { get; set; }

    [Required]
    [DataType(DataType.Password)]
    [Display(Name = "Password")]
    public string Password { get; set; }

    [DataType(DataType.Password)]
    [Display(Name = "Confirm password")]
    [Compare("Password", ErrorMessage = "The password and confirmation password do not match.")]
    public string ConfirmPassword { get; set; }

    public string Code { get; set; }
}

Finally create view for resetting password:
@model TreeTag.Models.ResetPasswordViewModel
@{
    ViewBag.Title = "Reset password";
}

<h2></h2>

@using (Html.BeginForm("ResetPassword", "Account", FormMethod.Post, new { @class = "form-horizontal", role = "form" }))
{
    @Html.AntiForgeryToken()
    <h4>Reset your password.</h4>
    <hr />
    @Html.ValidationSummary("", new { @class = "text-danger" })
    @Html.HiddenFor(model => model.Code)
    <div class="form-group">
        @Html.LabelFor(m => m.Email, new { @class = "col-md-2 control-label" })
        <div class="col-md-10">
            @Html.TextBoxFor(m => m.Email, new { @class = "form-control" })
        </div>
    </div>
    <div class="form-group">
        @Html.LabelFor(m => m.Password, new { @class = "col-md-2 control-label" })
        <div class="col-md-10">
            @Html.PasswordFor(m => m.Password, new { @class = "form-control" })
        </div>
    </div>
    <div id="confirm_password" class="form-group">
        @Html.LabelFor(m => m.ConfirmPassword, new { @class = "col-md-2 control-label" })
        <div class="col-md-10">
            @Html.PasswordFor(m => m.ConfirmPassword, new { @class = "form-control" })
        </div>
    </div>
    <div class="form-group">
        <div class="col-md-offset-2 col-md-10">
            <input type="submit" class="btn btn-default" value="Reset" />
        </div>
    </div>
}

