gistfile1.cs

 [AllowAnonymous]
    public class AuthenticationController: ApiController
    {
        private readonly IFormsAuthWrapper _formsAuth;

        public AuthenticationController(IFormsAuthWrapper formsAuth)
        {
            _formsAuth = formsAuth;
        }

        public HttpResponseMessage Token([FromBody]TokenRequest tokenRequest)
        {
            if (tokenRequest == null)
            {
                return Request.CreateErrorResponse(HttpStatusCode.BadRequest, "Cannot parse input parameters");
            }

            if (Membership.ValidateUser(tokenRequest.Username, tokenRequest.Password))
            {
                return Request.CreateResponse(HttpStatusCode.Created, new TokenResult
                    {
                        Success = true,
                        Token = _formsAuth.GetAuthToken(tokenRequest.Username, tokenRequest.Persist)
                    });
            }

            return Request.CreateErrorResponse(HttpStatusCode.Unauthorized, "Wrong username or password");
        }
    }