isCached method

Future<bool> isCached(NativeStepFingerprint fingerprint)

Check if a step with the given fingerprint has been cached.

Returns true if the cache entry exists and its outputs are still valid.

Implementation

Future<bool> isCached(NativeStepFingerprint fingerprint) async {
  final metaFile = _metaFile(fingerprint);
  if (!metaFile.existsSync()) {
    logger?.fine('Cache miss for ${fingerprint.id} (no metadata)');
    return false;
  }

  try {
    final json =
        jsonDecode(await metaFile.readAsString()) as Map<String, dynamic>;
    final cachedHash = json['hash'] as String?;
    if (cachedHash != fingerprint.hash) {
      logger?.fine(
        'Cache miss for ${fingerprint.id}: '
        'hash mismatch (cached=$cachedHash, current=${fingerprint.hash})',
      );
      return false;
    }

    // Verify all recorded output files still exist
    final outputs = (json['outputs'] as List<dynamic>?) ?? [];
    for (final output in outputs) {
      final path = output as String;
      if (!File(path).existsSync()) {
        logger?.fine(
          'Cache miss for ${fingerprint.id}: output missing at $path',
        );
        return false;
      }
    }

    logger?.fine('Cache hit for ${fingerprint.id}');
    return true;
  } catch (e) {
    logger?.warning('Cache read error for ${fingerprint.id}: $e');
    return false;
  }
}