DirectoryStorage is a Storage for ZODB, the object database used by Zope. It uses ordinary files and directories to store revisions of ZODB objects; one file per revision per object.

The following features differentiate DirectoryStorage from other storages:

  1. A very simple file format; one file per revision per object. Your data is not locked away inside an unfamiliar, opaque database.
  2. Designed for disaster-preparedness. Restore service after a disaster faster and with greater confidence.
  3. Storage Replication. Efficiently and robustly keep an online backup copy of your storage up to date with the latest changes from the master.
  4. Designed for fault tolerance. Any bugs (in DirectoryStorage, or elsewhere) are less likely to irretrievably destroy your data.
  5. But thats not all.


DirectoryStorage is subject to the provisions of the GNU Lesser General Public License version 2.1

Current Status

The current stable release of DirectoryStorage is version 1.1.20, released March 2011.

Versions earlier than 1.1.4 have defects that can cause loss of service. It is worth upgrading at your convenience if you are using anything earlier that 1.1.4.

Versions earlier than 1.1.2 have a serious bug that can lead to data loss (but only if used without ZEO). If you are using anything earlier than 1.1.2 then you should upgrade immediately.

Current versions of ZEO have problems restoring full service with DirectoryStorage if the ZEO server restarts while the ZEO client remains running. Full details in the Zope tracker.


DirectoryStorage was developed and is currently being maintained by Toby Dickenson, Zope 3 support and other contributions by Philipp von Weitershausen.