Persistence unified

Revision as of 09:50, 17 August 2007 by Marco Piccioni (Talk | contribs) (A tentative manifesto)

Unified persistence for Eiffel

This project is about developing a single, integrated and simple persistence framework for Eiffel.

Single because nothing else should be needed to access any kind of persistence services.

Integrated because aims at integrating both the already existing technologies and frameworks, as far as they deliver the intended benefits, and possibly new ones.

Simple because it should be very easy to use, removing all the unnecessary complexity.

A tentative manifesto

The first proposed task is to agree upon a sort of ‘manifesto’ of desirable features of the framework.

Here is a first proposal:

  • The framework should provide just three abstractions to the developer: PERSISTENCE_MEDIUM, PERSISTENCE_FORMAT and PERSISTENCE_MANAGER
Possible specializations of these abstractions could be: 
-FILE_MEDIUM, NETWORK_MEDIUM, RELATIONAL_DB_MEDIUM, CUSTOM_MEDIUM, 
-BINARY_FORMAT, STRING_FORMAT, XML_FORMAT, DADL_FORMAT, CUSTOM_FORMAT,
-SERIALIZATION_MANAGER, RDBMS_MANAGER, CUSTOM_MANAGER
  • Classes which objects have to be persisted should not be polluted with persistence code, for example adding specific persistence-related attributes or by inhering from some other class that provides persistence services
  • The access to the persistence services should be as uniform as possible. This can be achieved using the XXX_MANAGER class hierarchy that handles access to specific kinds of persistence stores