read method

@override Future<CachedAssetEntry?> read(String sourceUri)

Implementation

@override
Future<CachedAssetEntry?> read(String sourceUri) async {
  if (_loadedKeys.contains(sourceUri)) {
    return _entries[sourceUri];
  }

  _loadedKeys.add(sourceUri);
  final metadataFile = _metadataFileFor(sourceUri);
  if (!await metadataFile.exists()) {
    return null;
  }

  try {
    final decoded = jsonDecode(await metadataFile.readAsString());
    if (decoded is! Map) {
      await _deleteEntryFiles(sourceUri);
      return null;
    }

    final entry = CachedAssetEntry.fromJson(
      decoded.map((key, value) => MapEntry(key.toString(), value)),
    );
    if (!await File(entry.filePath).exists()) {
      await _deleteEntryFiles(sourceUri);
      return null;
    }

    _entries[sourceUri] = entry;
    return entry;
  } catch (_) {
    await _deleteEntryFiles(sourceUri);
    return null;
  }
}