The Filesystem Datasource returns records according to a fixed schema that contains the following fields:
Name (String): The file name without any extension (the characters after the last '.').
Extension (String): The file extension (not including the '.').
Directory (String): The directory containing the file.
Size (Long): The file size in bytes.
LastModified (Long): The numeric value of the last modified date.
LastModifiedDate (Timestamp): The timestamp value of the last modified date.
Path (String): The full path of the file, comprising directory, name and extension.
URL (String): The url of the file, using the file:/ protocol.