+++ /dev/null
-# Copyright 2011 GRNET S.A. All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or
-# without modification, are permitted provided that the following
-# conditions are met:
-#
-# 1. Redistributions of source code must retain the above
-# copyright notice, this list of conditions and the following
-# disclaimer.
-#
-# 2. Redistributions in binary form must reproduce the above
-# copyright notice, this list of conditions and the following
-# disclaimer in the documentation and/or other materials
-# provided with the distribution.
-#
-# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
-# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
-# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
-# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
-# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
-# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-# POSSIBILITY OF SUCH DAMAGE.
-#
-# The views and conclusions contained in the software and
-# documentation are those of the authors and should not be
-# interpreted as representing official policies, either expressed
-# or implied, of GRNET S.A.
-
-from collections import defaultdict
-from sqlalchemy import Table, Column, String, Integer, MetaData, ForeignKey
-from sqlalchemy.sql import select, and_
-from sqlalchemy.schema import Index
-from sqlalchemy.sql.expression import desc
-
-from dbworker import DBWorker
-
-
-class XFeatures(DBWorker):
- """XFeatures are path properties that allow non-nested
- inheritance patterns. Currently used for storing permissions.
- """
-
- def __init__(self, **params):
- DBWorker.__init__(self, **params)
- metadata = MetaData()
- columns=[]
- columns.append(Column('feature_id', Integer, primary_key=True))
- columns.append(Column('path', String(2048)))
- self.xfeatures = Table('xfeatures', metadata, *columns)
- # place an index on path
- Index('idx_features_path', self.xfeatures.c.path)
-
- columns=[]
- columns.append(Column('feature_id', Integer,
- ForeignKey('xfeatures.feature_id',
- ondelete='CASCADE'),
- primary_key=True))
- columns.append(Column('key', Integer, primary_key=True,
- autoincrement=False))
- columns.append(Column('value', String(255), primary_key=True))
- self.xfeaturevals = Table('xfeaturevals', metadata, *columns)
-
- metadata.create_all(self.engine)
-
- def xfeature_inherit(self, path):
- """Return the (path, feature) inherited by the path, or None."""
-
- s = select([self.xfeatures.c.path, self.xfeatures.c.feature_id])
- s = s.where(self.xfeatures.c.path <= path)
- s = s.order_by(desc(self.xfeatures.c.path)).limit(1)
- r = self.conn.execute(s)
- row = r.fetchone()
- r.close()
- if row and path.startswith(row[0]):
- return row
- else:
- return None
-
- def xfeature_list(self, path):
- """Return the list of the (prefix, feature) pairs matching path.
- A prefix matches path if either the prefix includes the path,
- or the path includes the prefix.
- """
-
- inherited = self.xfeature_inherit(path)
- if inherited:
- return [inherited]
-
- s = select([self.xfeatures.c.path, self.xfeatures.c.feature_id])
- s = s.where(and_(self.xfeatures.c.path.like(path + '%'),
- self.xfeatures.c.path != path))
- s = s.order_by(self.xfeatures.c.path)
- r = self.conn.execute(s)
- l = r.fetchall()
- r.close()
- return l
-
- def xfeature_create(self, path):
- """Create and return a feature for path.
- If the path already inherits a feature or
- bestows to paths already inheriting a feature,
- create no feature and return None.
- If the path has a feature, return it.
- """
-
- prefixes = self.xfeature_list(path)
- pl = len(prefixes)
- if (pl > 1) or (pl == 1 and prefixes[0][0] != path):
- return None
- if pl == 1 and prefixes[0][0] == path:
- return prefixes[0][1]
- s = self.xfeatures.insert()
- r = self.conn.execute(s, path=path)
- inserted_primary_key = r.inserted_primary_key[0]
- r.close()
- return inserted_primary_key
-
- def xfeature_destroy(self, path):
- """Destroy a feature and all its key, value pairs."""
-
- s = self.xfeatures.delete().where(self.xfeatures.c.path == path)
- r = self.conn.execute(s)
- r.close()
-
- def feature_dict(self, feature):
- """Return a dict mapping keys to list of values for feature."""
-
- s = select([self.xfeaturevals.c.key, self.xfeaturevals.c.value])
- s = s.where(self.xfeaturevals.c.feature_id == feature)
- r = self.conn.execute(s)
- d = defaultdict(list)
- for key, value in r.fetchall():
- d[key].append(value)
- r.close()
- return d
-
- def feature_set(self, feature, key, value):
- """Associate a key, value pair with a feature."""
-
- s = self.xfeaturevals.select()
- s = s.where(self.xfeaturevals.c.feature_id == feature)
- s = s.where(self.xfeaturevals.c.key == key)
- s = s.where(self.xfeaturevals.c.value == value)
- r = self.conn.execute(s)
- xfeaturevals = r.fetchall()
- r.close()
- if len(xfeaturevals) == 0:
- s = self.xfeaturevals.insert()
- r = self.conn.execute(s, feature_id=feature, key=key, value=value)
- r.close()
-
- def feature_setmany(self, feature, key, values):
- """Associate the given key, and values with a feature."""
-
- #TODO: more efficient way to do it
- for v in values:
- self.feature_set(feature, key, v)
-
- def feature_unset(self, feature, key, value):
- """Disassociate a key, value pair from a feature."""
-
- s = self.xfeaturevals.delete()
- s = s.where(and_(self.xfeaturevals.c.feature_id == feature,
- self.xfeaturevals.c.key == key,
- self.xfeaturevals.c.value == value))
- r = self.conn.execute(s)
- r.close()
-
- def feature_unsetmany(self, feature, key, values):
- """Disassociate the key for the values given, from a feature."""
-
- for v in values:
- conditional = and_(self.xfeaturevals.c.feature_id == feature,
- self.xfeaturevals.c.key == key,
- self.xfeaturevals.c.value == v)
- s = self.xfeaturevals.delete().where(conditional)
- r = self.conn.execute(s)
- r.close()
-
- def feature_get(self, feature, key):
- """Return the list of values for a key of a feature."""
-
- s = select([self.xfeaturevals.c.value])
- s = s.where(and_(self.xfeaturevals.c.feature_id == feature,
- self.xfeaturevals.c.key == key))
- r = self.conn.execute(s)
- l = [row[0] for row in r.fetchall()]
- r.close()
- return l
-
- def feature_clear(self, feature, key):
- """Delete all key, value pairs for a key of a feature."""
-
- s = self.xfeaturevals.delete()
- s = s.where(and_(self.xfeaturevals.c.feature_id == feature,
- self.xfeaturevals.c.key == key))
- r = self.conn.execute(s)
- r.close()
projects / pithos / blobdiff