jan: thuban/Thuban/UI extensionregistry.py,NONE,1.1

[cvs@intevation.de]

Author: jan

Update of /thubanrepository/thuban/Thuban/UI
In directory doto:/tmp/cvs-serv10669

Added Files:
	extensionregistry.py 
Log Message:
This module defines a registry for Extensions.


--- NEW FILE: extensionregistry.py ---
# Copyright (C) 2004 by Intevation GmbH
# Authors:
# Jan-Oliver Wagner <jan at intevation.de>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with Thuban for details.

"""
Registry for Extensions.

This module defines a registry for Extensions.
This is basically used for displaying information on
the active Extensions in the general About-Dialog.
A registration is not mandatory to make a Extension
work, but any Extension should register to provide
a complete information in the Thuban About Dialog.

A Extension should define a ExtensionDesc object
and apply ext_registry.add() to register it.
"""

__version__ = "$Revision: 1.1 $"
# $Source: /thubanrepository/thuban/Thuban/UI/extensionregistry.py,v $
# $Id: extensionregistry.py,v 1.1 2004/09/28 19:13:21 jan Exp $

class ExtensionDesc:

    """
    A description of a Thuban Extension.
    """

    def __init__(self, name, version, authors, copyright, desc):
        """
        Initialize a new Thuban Extension information.

        name -- The name of the Thuban Extension.
                Example: 'gns2shp'

        version -- The version number of the Thuban Extension.
                   Example: '1.0.0'

        authors -- List of authors.
                   Example: [ 'Jan-Oliver Wagner' ]

        copyright -- Copyright notice.
                     Example: '2003, 2004 Intevation GmbH'

        desc -- Short description of the Thuban Extension.
                Example: _('''
                         Converts GNS (Geographical Name Service of NIMA)
                         to Shapefile format and displays the data.
                         ''')

        """
        self.name = name
        self.version = version
        self.authors = authors
        self.copyright = copyright
        self.desc = desc

class ExtensionRegistry:

    """
    A ExtensionRegistry keeps information on the registered
    Thuban Extensions.

    The registry will raise a exception either when the version
    required for the Extensions exceeds the version of the currently
    running Thuban or if the name of a registered extension already
    is used for registering another extension.
    """

    def __init__(self):
        self.registry = []

    def __nonzero__(self):
        return len(self.registry) <> 0

    def __iter__(self):
        return iter(self.registry)

    def add(self, ext):
        self.registry.append(ext)


# The central Thuban Extensions registry
ext_registry = ExtensionRegistry()