zope.filerepresentation API

File-system representation interfaces

The interfaces defined here are used for file-system and file-system-like representations of objects, such as file-system synchronization, FTP, PUT, and WebDAV.

There are three issues we need to deal with:

  • File system representation

    Every object is either a directory or a file.

  • Properties

    There are two kinds of properties:

    • Data properties

      Data properties are handled directly by the object implementation.

    • Meta-data properties

      Meta data properties are handled via annotations.

  • Completeness

    We must have a complete lossless data representation for file-system synchronization. This is achieved through serialization of:

    • All annotations (not just properties), and

    • Extra data.

Strategies for common access mechanisms:

  • FTP

    For getting directory info (static) information:

    • Use Zope DublinCore to get modification times

    • Show as readable if we can access a read method.

    • Show as writable if we can access a write method.

  • FTP and WebDAV

    • Treat as a directory if there is an adapter to IReadDirectory. Treat as a file otherwise.

    • For creating objects:

      • Directories:

        Look for an IDirectoryFactory adapter.

      • Files

        First look for a IFileFactory adapter with a name that is the same as the extention (e.g. “.pt”).

        Then look for an unnamed IFileFactory adapter.

  • File-system synchronization

    Because this must be lossless, we will use class-based adapters for this, but we want to make it as easy as possible to use other adapters as well.

    For reading, there must be a class adapter to IReadSync. We will then apply rules similar to those above.