derive static method

Uint8List derive(
  1. String secret,
  2. String label
)

The 32-byte key for label, made from secret. It is made once per isolate, then read from a cache.

Implementation

static Uint8List derive(String secret, String label) {
  /// secret, then label: no string is built per call
  Map<String, Uint8List> keys = _cache[secret] ??= <String, Uint8List>{};
  return keys[label] ??= hkdf(utf8.encode(secret), utf8.encode(label));
}