public void SignString()
{
HmacSHA1Signer instance = new HmacSHA1Signer();
string sign = instance.SignString("foo", "secret");
Assert.Equal("m67ZG+f1i1fIJLYNp8smKy7K+9I=", sign);
}
/// <summary>
///
/// </summary>
/// <param name="request"></param>
/// <param name="signString"></param>
private void AddHeader(HttpRequestMessage request, string signString)
{
var timeStamp = DateTimeOffset.Now.ToUnixTimeMilliseconds();
request.Headers.Add("Spas-AccessKey", _accessKey);
request.Headers.Add("timeStamp", $"{timeStamp}");
request.Headers.Add("Spas-Signature", _hmacSHA1.SignString($"{signString}+{timeStamp}", _secretKey));
}