Synnefo » Pithos

# 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 xfeatures import XFeatures

from groups import Groups

from public import Public

class Permissions(XFeatures, Groups, Public):

    def __init__(self, **params):

        XFeatures.__init__(self, **params)

        Groups.__init__(self, **params)

        Public.__init__(self, **params)

    def access_grant(self, access, path, member='all', members=()):

        """Grant a member with an access to a path."""

        xfeatures = self.xfeature_list(path)

        xfl = len(xfeatures)

        if xfl > 1 or (xfl == 1 and xfeatures[0][0] != path):

            return xfeatures

        if xfl == 0:

            feature = self.alloc_serial()

            self.xfeature_bestow(path, feature)

        else:

            fpath, feature = xfeatures[0]

        if members:

            self.feature_setmany(feature, access, members)

        else:

            self.feature_set(feature, access, member)

        return ()

    def access_revoke(self, access, path, member='all', members=()):

        """Revoke access to path from members.

           Note that this will not revoke access for members

           that are indirectly granted access through group membership.

        """

        # XXX: Maybe provide a force_revoke that will kick out

        #      all groups containing the given members?

        xfeatures = self.xfeature_list(path)

        xfl = len(xfeatures)

        if xfl != 1 or xfeatures[0][0] != path:

            return xfeatures

        fpath, feature = xfeatures[0]

        if members:

            self.feature_unsetmany(feature, access, members=members)

        else:

            self.feature_unset(feature, access, member)

        # XXX: provide a meaningful return value? 

        return ()

    def access_check(self, access, path, member):

        """Return true if the member has this access to the path."""

        r = self.xfeature_inherit(path)

        if not r:

            return 0

        fpath, feature = r

        memberset = set(self.feature_get(feature, access))

        if member in memberset:

            return 1

        for group in self.group_parents(self, member):

            if group in memberset:

                return 1

        return 0

    def access_list(self, path):

        """Return the list of (access, member) pairs for the path."""

        r = self.xfeature_inherit(path)

        if not r:

            return ()

        fpath, feature = r

        return self.feature_list(feature)

    def access_list_paths(self, member):

        """Return the list of (access, path) pairs granted to member."""

        q = ("select distinct key, path from xfeatures inner join "

             "   (select distinct feature, key from xfeaturevals inner join "

             "      (select name as value from members "

             "       where member = ? union select ?) "

             "    using (value)) "

             "using (feature)")

        self.execute(q, (member, member))

        return self.fetchall()