public HttpResponseMessage Get()
 {
     string content = new BrainTreeService().GenerateClientToken();
     return new HttpResponseMessage()
     {
         Content = new StringContent(content)
     };
 }
        public void GenerateClientToken_WhenClientNeedsToPay_ReturnClientToken()
        {
            //Arrange
            string clientToken = string.Empty;

            //Act
            clientToken = new BrainTreeService().GenerateClientToken();

            //Assert
            Assert.IsNotNullOrEmpty(clientToken);
        }