buildSha256 method
Implementation
String buildSha256(String key, [Map<String, dynamic>? access]) {
String timestamp = DateTime.now().millisecondsSinceEpoch.toString();
String stringForHash =
key + timestamp + (access == null ? '' : access.toString());
Uint8List bytes = utf8.encode(stringForHash);
var hash = sha256.convert(bytes);
return hash.toString();
}