Use this to test webapi endpoints without having to build a working authentication system.

DummyAuthenticationHandler.cs

    //# setup:  config.MessageHandlers.Add(new DummyAuthenticationHandler());
    public class DummyAuthenticationHandler : DelegatingHandler
    {
        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
        {
            if (string.IsNullOrWhiteSpace(Thread.CurrentPrincipal.Identity.AuthenticationType))
            {
                var claims =
                    new List<Claim>
                    {
                        new Claim(ClaimTypes.Name, "john.doe"),
                        new Claim(ClaimTypes.Email, "john.doe@outlook.com"),
                        new Claim("TenantId", "66D9BE38-3054-4C8B-9EC7-EF7782A35CA4"),
                        new Claim("TenantName", "New Client"),
                    };

                var id = new ClaimsIdentity(claims, "dummy");
                var principal = new ClaimsPrincipal(id);


                Thread.CurrentPrincipal = principal;

                if (HttpContext.Current != null)
                    HttpContext.Current.User = principal;
            }
            return base.SendAsync(request, cancellationToken);
        }
    }