8660f12f5e
git-svn-id: svn://svn.cy55.de/Zope3/src/loops/trunk@2422 fd906abe-77d9-0310-91a1-e0d9ade77398
76 lines
2.4 KiB
Python
76 lines
2.4 KiB
Python
#
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# Copyright (c) 2008 Helmut Merz helmutm@cy55.de
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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#
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"""
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Filtering query result sets.
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$Id$
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"""
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from zope.interface import Interface, Attribute
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class IQuery(Interface):
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""" A query or
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"""
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def apply():
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""" Return the result set for this query.
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"""
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class IQueryInstance(Interface):
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""" A top-level query instance that allows caching of intermediate
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results when the underlying queries and filters are applied.
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"""
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query = Attribute('The top-level query (query term).')
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filters = Attribute('A collection of filters that will be applied '
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'to the result of the query.')
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def apply(uidsOnly=False):
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""" Execute the query and apply the filters; return a mapping
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of UIDs to objects or a set of UIDs only if the ``uidsOnly``
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argument is set to True.
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"""
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class IFilter(Interface):
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""" A filter is a query that will be ``and``-connected to a query.
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"""
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def query():
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""" Return the query that corresponds to this filter; that will then
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typically be ``and``-joined to another query.
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May return None; in this case the ``apply()`` method must be used.
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"""
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def apply(objects, queryInstance=None):
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""" Apply the filter to the set of objects specified as a mapping
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of UIDs to objects.
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If a query instance is given it may be used for caching
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intermediate results.
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"""
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def check(obj, queryInstance=None):
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""" Return True if the object given should be included in the
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filter's result set, False otherwise.
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If a query instance is given it may be used for caching.
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"""
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