issue method

Implementation

String issue({
  required String actionId,
  required Map<String, String> values,
}) {
  final action = actionId.trim();
  if (!isValidSeoInteractionId(action)) {
    throw ArgumentError.value(
      actionId,
      'actionId',
      'is not a valid action id',
    );
  }
  final canonical = _canonicalContext(values);
  if (canonical == null) {
    throw ArgumentError.value(values, 'values', 'is not a valid context map');
  }
  final lifetime = tokenLifetime;
  final Map<String, Object> envelope;
  if (lifetime == null) {
    envelope = _unboundedEnvelope(action, canonical);
  } else {
    final issuedAt = _epochMilliseconds(_clock());
    envelope = _expiringEnvelope(
      action,
      canonical,
      issuedAt: issuedAt,
      expiresAt: issuedAt + lifetime.inMilliseconds,
    );
  }
  final payload = utf8.encode(jsonEncode(envelope));
  final body = _withoutPadding(base64Url.encode(payload));
  final signature = _signature(payload);
  final token = '$body.$signature';
  if (token.length > seoActionFormMaxContextTokenLength) {
    throw ArgumentError.value(
        values, 'values', 'produces an oversized token');
  }
  return token;
}