Generate a Token

Token Generation Proposal

        public TokenRecord GenerateToken(string url, string user, string key)
        {
            var expiration = (long)DateTime.UtcNow.AddMinutes(30).Subtract(DateTime.UnixEpoch).TotalSeconds;
            var endpoint = HttpUtility.UrlEncode(url);

            using var hash = new HMACSHA256(Encoding.UTF8.GetBytes(key));
            var signature = HttpUtility.UrlEncode(Convert.ToBase64String(hash.ComputeHash(Encoding.UTF8.GetBytes($"{endpoint}\n{expiration}"))));

            hash.Dispose();
            return new TokenRecord($"SharedAccessSignature sr={endpoint}&sig={signature}&se={expiration}&skn={user}", DateTime.UnixEpoch.AddSeconds(expiration));
        }