Forest: a language and toolkit for programming with filestores

Abstract

A filestore is a structured collection of data files housed in a conventional hierarchical file system. Many applications use filestores as a poor-man's database, and the correct execution of these applications requires that the collection of files, directories, and symbolic links stored on disk satisfy a variety of precise invariants. Moreover, all of these structures must have acceptable ownership, permission, and timestamp attributes. Unfortunately, current programming languages do not provide support for documenting assumptions about filestores, detecting errors in them, or safely loading from and storing to them.