public HttpResponseMessage Get(string blobName)
        {
            const string containerName       = "images";
            const string containerPolicyName = "demopolicy";

            _helper.SetContainerPolicy(containerName, containerPolicyName);

            string sas = _helper.GenerateSharedAccessSignature(blobName, containerName, containerPolicyName);

            return(new HttpResponseMessage
            {
                Content = new StringContent(sas),
                StatusCode = HttpStatusCode.OK
            });
        }