fixed a bug in cache invalidation

rhodecode/model/db.py

@@ -1,800 +1,800 b''
 # -*- coding: utf-8 -*-
 """
     rhodecode.model.db
     ~~~~~~~~~~~~~~~~~~
 
     Database Models for RhodeCode
 
     :created_on: Apr 08, 2010
     :author: marcink
     :copyright: (C) 2009-2011 Marcin Kuzminski <[e-mail]>
     :license: GPLv3, see COPYING for more details.
 """
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
 import logging
 import datetime
 import traceback
 from datetime import date
 
 from sqlalchemy import *
 from sqlalchemy.exc import DatabaseError
 from sqlalchemy.orm import relationship, backref, joinedload, class_mapper
 from sqlalchemy.orm.interfaces import MapperExtension
 
 from beaker.cache import cache_region, region_invalidate
 
 from vcs import get_backend
 from vcs.utils.helpers import get_scm
 from vcs.exceptions import RepositoryError, VCSError
 from vcs.utils.lazy import LazyProperty
 from vcs.nodes import FileNode
 
 from rhodecode.lib import str2bool, json, safe_str
 from rhodecode.model.meta import Base, Session
 from rhodecode.model.caching_query import FromCache
 
 log = logging.getLogger(__name__)
 
 #==============================================================================
 # BASE CLASSES
 #==============================================================================
 
 class ModelSerializer(json.JSONEncoder):
     """
     Simple Serializer for JSON,
     
     usage::
         
         to make object customized for serialization implement a __json__
         method that will return a dict for serialization into json
         
     example::
         
         class Task(object):
         
             def __init__(self, name, value):
                 self.name = name
                 self.value = value
         
             def __json__(self):
                 return dict(name=self.name,
                             value=self.value)     
         
     """
 
     def default(self, obj):
 
         if hasattr(obj, '__json__'):
             return obj.__json__()
         else:
             return json.JSONEncoder.default(self, obj)
 
 class BaseModel(object):
     """Base Model for all classess
 
     """
 
     @classmethod
     def _get_keys(cls):
         """return column names for this model """
         return class_mapper(cls).c.keys()
 
     def get_dict(self):
         """return dict with keys and values corresponding
         to this model data """
 
         d = {}
         for k in self._get_keys():
             d[k] = getattr(self, k)
         return d
 
     def get_appstruct(self):
         """return list with keys and values tupples corresponding
         to this model data """
 
         l = []
         for k in self._get_keys():
             l.append((k, getattr(self, k),))
         return l
 
     def populate_obj(self, populate_dict):
         """populate model with data from given populate_dict"""
 
         for k in self._get_keys():
             if k in populate_dict:
                 setattr(self, k, populate_dict[k])
 
     @classmethod
     def query(cls):
         return Session.query(cls)
 
     @classmethod
     def get(cls, id_):
         return Session.query(cls).get(id_)
 
 
 class RhodeCodeSettings(Base, BaseModel):
     __tablename__ = 'rhodecode_settings'
     __table_args__ = (UniqueConstraint('app_settings_name'), {'extend_existing':True})
     app_settings_id = Column("app_settings_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     app_settings_name = Column("app_settings_name", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     app_settings_value = Column("app_settings_value", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
 
     def __init__(self, k='', v=''):
         self.app_settings_name = k
         self.app_settings_value = v
 
     def __repr__(self):
         return "<%s('%s:%s')>" % (self.__class__.__name__,
                                   self.app_settings_name, self.app_settings_value)
 
 
     @classmethod
     def get_by_name(cls, ldap_key):
         return Session.query(cls)\
             .filter(cls.app_settings_name == ldap_key).scalar()
 
     @classmethod
     def get_app_settings(cls, cache=False):
 
         ret = Session.query(cls)
 
         if cache:
             ret = ret.options(FromCache("sql_cache_short", "get_hg_settings"))
 
         if not ret:
             raise Exception('Could not get application settings !')
         settings = {}
         for each in ret:
             settings['rhodecode_' + each.app_settings_name] = \
                 each.app_settings_value
 
         return settings
 
     @classmethod
     def get_ldap_settings(cls, cache=False):
         ret = Session.query(cls)\
                 .filter(cls.app_settings_name.startswith('ldap_'))\
                 .all()
         fd = {}
         for row in ret:
             fd.update({row.app_settings_name:row.app_settings_value})
 
         fd.update({'ldap_active':str2bool(fd.get('ldap_active'))})
 
         return fd
 
 
 class RhodeCodeUi(Base, BaseModel):
     __tablename__ = 'rhodecode_ui'
     __table_args__ = {'extend_existing':True}
     ui_id = Column("ui_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     ui_section = Column("ui_section", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     ui_key = Column("ui_key", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     ui_value = Column("ui_value", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     ui_active = Column("ui_active", Boolean(), nullable=True, unique=None, default=True)
 
 
     @classmethod
     def get_by_key(cls, key):
         return Session.query(cls).filter(cls.ui_key == key)
 
 
 class User(Base, BaseModel):
     __tablename__ = 'users'
     __table_args__ = (UniqueConstraint('username'), UniqueConstraint('email'), {'extend_existing':True})
     user_id = Column("user_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     username = Column("username", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     password = Column("password", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     active = Column("active", Boolean(), nullable=True, unique=None, default=None)
     admin = Column("admin", Boolean(), nullable=True, unique=None, default=False)
     name = Column("name", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     lastname = Column("lastname", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     email = Column("email", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     last_login = Column("last_login", DateTime(timezone=False), nullable=True, unique=None, default=None)
     ldap_dn = Column("ldap_dn", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     api_key = Column("api_key", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
 
     user_log = relationship('UserLog', cascade='all')
     user_perms = relationship('UserToPerm', primaryjoin="User.user_id==UserToPerm.user_id", cascade='all')
 
     repositories = relationship('Repository')
     user_followers = relationship('UserFollowing', primaryjoin='UserFollowing.follows_user_id==User.user_id', cascade='all')
     repo_to_perm = relationship('RepoToPerm', primaryjoin='RepoToPerm.user_id==User.user_id', cascade='all')
 
     group_member = relationship('UsersGroupMember', cascade='all')
 
     @property
     def full_contact(self):
         return '%s %s <%s>' % (self.name, self.lastname, self.email)
 
     @property
     def short_contact(self):
         return '%s %s' % (self.name, self.lastname)
 
     @property
     def is_admin(self):
         return self.admin
 
     def __repr__(self):
         try:
             return "<%s('id:%s:%s')>" % (self.__class__.__name__,
                                              self.user_id, self.username)
         except:
             return self.__class__.__name__
 
     @classmethod
     def by_username(cls, username, case_insensitive=False):
         if case_insensitive:
             return Session.query(cls).filter(cls.username.like(username)).one()
         else:
             return Session.query(cls).filter(cls.username == username).one()
 
     @classmethod
     def get_by_api_key(cls, api_key):
         return Session.query(cls).filter(cls.api_key == api_key).one()
 
 
     def update_lastlogin(self):
         """Update user lastlogin"""
 
         self.last_login = datetime.datetime.now()
         Session.add(self)
         Session.commit()
         log.debug('updated user %s lastlogin', self.username)
 
 
 class UserLog(Base, BaseModel):
     __tablename__ = 'user_logs'
     __table_args__ = {'extend_existing':True}
     user_log_id = Column("user_log_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     user_id = Column("user_id", Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)
     repository_id = Column("repository_id", Integer(), ForeignKey('repositories.repo_id'), nullable=False, unique=None, default=None)
     repository_name = Column("repository_name", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     user_ip = Column("user_ip", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     action = Column("action", UnicodeText(length=1200000, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     action_date = Column("action_date", DateTime(timezone=False), nullable=True, unique=None, default=None)
 
     @property
     def action_as_day(self):
         return date(*self.action_date.timetuple()[:3])
 
     user = relationship('User')
     repository = relationship('Repository')
 
 
 class UsersGroup(Base, BaseModel):
     __tablename__ = 'users_groups'
     __table_args__ = {'extend_existing':True}
 
     users_group_id = Column("users_group_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     users_group_name = Column("users_group_name", String(length=255, convert_unicode=False, assert_unicode=None), nullable=False, unique=True, default=None)
     users_group_active = Column("users_group_active", Boolean(), nullable=True, unique=None, default=None)
 
     members = relationship('UsersGroupMember', cascade="all, delete, delete-orphan", lazy="joined")
 
 
     @classmethod
     def get_by_group_name(cls, group_name, cache=False, case_insensitive=False):
         if case_insensitive:
             gr = Session.query(cls)\
             .filter(cls.users_group_name.ilike(group_name))
         else:
             gr = Session.query(UsersGroup)\
                 .filter(UsersGroup.users_group_name == group_name)
         if cache:
             gr = gr.options(FromCache("sql_cache_short",
                                           "get_user_%s" % group_name))
         return gr.scalar()
 
 class UsersGroupMember(Base, BaseModel):
     __tablename__ = 'users_groups_members'
     __table_args__ = {'extend_existing':True}
 
     users_group_member_id = Column("users_group_member_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     users_group_id = Column("users_group_id", Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)
     user_id = Column("user_id", Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)
 
     user = relationship('User', lazy='joined')
     users_group = relationship('UsersGroup')
 
     def __init__(self, gr_id='', u_id=''):
         self.users_group_id = gr_id
         self.user_id = u_id
 
 class Repository(Base, BaseModel):
     __tablename__ = 'repositories'
     __table_args__ = (UniqueConstraint('repo_name'), {'extend_existing':True},)
 
     repo_id = Column("repo_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     repo_name = Column("repo_name", String(length=255, convert_unicode=False, assert_unicode=None), nullable=False, unique=True, default=None)
     clone_uri = Column("clone_uri", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=False, default=None)
     repo_type = Column("repo_type", String(length=255, convert_unicode=False, assert_unicode=None), nullable=False, unique=False, default='hg')
     user_id = Column("user_id", Integer(), ForeignKey('users.user_id'), nullable=False, unique=False, default=None)
     private = Column("private", Boolean(), nullable=True, unique=None, default=None)
     enable_statistics = Column("statistics", Boolean(), nullable=True, unique=None, default=True)
     enable_downloads = Column("downloads", Boolean(), nullable=True, unique=None, default=True)
     description = Column("description", String(length=10000, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     created_on = Column('created_on', DateTime(timezone=False), nullable=True, unique=None, default=datetime.datetime.now)
 
     fork_id = Column("fork_id", Integer(), ForeignKey('repositories.repo_id'), nullable=True, unique=False, default=None)
     group_id = Column("group_id", Integer(), ForeignKey('groups.group_id'), nullable=True, unique=False, default=None)
 
 
     user = relationship('User')
     fork = relationship('Repository', remote_side=repo_id)
     group = relationship('Group')
     repo_to_perm = relationship('RepoToPerm', cascade='all', order_by='RepoToPerm.repo_to_perm_id')
     users_group_to_perm = relationship('UsersGroupRepoToPerm', cascade='all')
     stats = relationship('Statistics', cascade='all', uselist=False)
 
     followers = relationship('UserFollowing', primaryjoin='UserFollowing.follows_repo_id==Repository.repo_id', cascade='all')
 
     logs = relationship('UserLog', cascade='all')
 
     def __repr__(self):
         return "<%s('%s:%s')>" % (self.__class__.__name__,
                                   self.repo_id, self.repo_name)
 
     @classmethod
     def by_repo_name(cls, repo_name):
         q = Session.query(cls).filter(cls.repo_name == repo_name)
 
         q = q.options(joinedload(Repository.fork))\
             .options(joinedload(Repository.user))\
             .options(joinedload(Repository.group))\
 
         return q.one()
 
     @classmethod
     def get_repo_forks(cls, repo_id):
         return Session.query(cls).filter(Repository.fork_id == repo_id)
 
     @property
     def just_name(self):
         return self.repo_name.split(os.sep)[-1]
 
     @property
     def groups_with_parents(self):
         groups = []
         if self.group is None:
             return groups
 
         cur_gr = self.group
         groups.insert(0, cur_gr)
         while 1:
             gr = getattr(cur_gr, 'parent_group', None)
             cur_gr = cur_gr.parent_group
             if gr is None:
                 break
             groups.insert(0, gr)
 
         return groups
 
     @property
     def groups_and_repo(self):
         return self.groups_with_parents, self.just_name
 
     @LazyProperty
     def repo_path(self):
         """
         Returns base full path for that repository means where it actually
         exists on a filesystem
         """
         q = Session.query(RhodeCodeUi).filter(RhodeCodeUi.ui_key == '/')
         q.options(FromCache("sql_cache_short", "repository_repo_path"))
         return q.one().ui_value
 
     @property
     def repo_full_path(self):
         p = [self.repo_path]
         # we need to split the name by / since this is how we store the
         # names in the database, but that eventually needs to be converted
         # into a valid system path
         p += self.repo_name.split('/')
         return os.path.join(*p)
 
     @property
     def _ui(self):
         """
         Creates an db based ui object for this repository
         """
         from mercurial import ui
         from mercurial import config
         baseui = ui.ui()
 
         #clean the baseui object
         baseui._ocfg = config.config()
         baseui._ucfg = config.config()
         baseui._tcfg = config.config()
 
 
         ret = Session.query(RhodeCodeUi)\
             .options(FromCache("sql_cache_short",
                                "repository_repo_ui")).all()
 
         hg_ui = ret
         for ui_ in hg_ui:
             if ui_.ui_active:
                 log.debug('settings ui from db[%s]%s:%s', ui_.ui_section,
                           ui_.ui_key, ui_.ui_value)
                 baseui.setconfig(ui_.ui_section, ui_.ui_key, ui_.ui_value)
 
         return baseui
 
     #==========================================================================
     # SCM CACHE INSTANCE
     #==========================================================================
 
     @property
     def invalidate(self):
         """
         Returns Invalidation object if this repo should be invalidated
         None otherwise. `cache_active = False` means that this cache
         state is not valid and needs to be invalidated
         """
         return Session.query(CacheInvalidation)\
             .filter(CacheInvalidation.cache_key == self.repo_name)\
             .filter(CacheInvalidation.cache_active == False)\
             .scalar()
 
     @property
     def set_invalidate(self):
         """
         set a cache for invalidation for this instance
         """
         inv = Session.query(CacheInvalidation)\
             .filter(CacheInvalidation.cache_key == self.repo_name)\
             .scalar()
 
         if inv is None:
             inv = CacheInvalidation(self.repo_name)
         inv.cache_active = True
         Session.add(inv)
         Session.commit()
 
     @property
     def scm_instance(self):
         return self.__get_instance()
 
     @property
     def scm_instance_cached(self):
         @cache_region('long_term')
         def _c(repo_name):
             return self.__get_instance()
 
         inv = self.invalidate
-        if inv:
+        if inv is not None:
             region_invalidate(_c, None, self.repo_name)
             #update our cache
-            inv.cache_key.cache_active = True
+            inv.cache_active = True
             Session.add(inv)
             Session.commit()
 
         # TODO: remove this trick when beaker 1.6 is released
         # and have fixed this issue
         rn = safe_str(self.repo_name)
 
         return _c(rn)
 
     def __get_instance(self):
 
         repo_full_path = self.repo_full_path
 
         try:
             alias = get_scm(repo_full_path)[0]
             log.debug('Creating instance of %s repository', alias)
             backend = get_backend(alias)
         except VCSError:
             log.error(traceback.format_exc())
             log.error('Perhaps this repository is in db and not in '
                       'filesystem run rescan repositories with '
                       '"destroy old data " option from admin panel')
             return
 
         if alias == 'hg':
 
             repo = backend(safe_str(repo_full_path), create=False,
                            baseui=self._ui)
             #skip hidden web repository
             if repo._get_hidden():
                 return
         else:
             repo = backend(repo_full_path, create=False)
 
         return repo
 
 
 class Group(Base, BaseModel):
     __tablename__ = 'groups'
     __table_args__ = (UniqueConstraint('group_name', 'group_parent_id'),
                       CheckConstraint('group_id != group_parent_id'), {'extend_existing':True},)
     __mapper_args__ = {'order_by':'group_name'}
 
     group_id = Column("group_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     group_name = Column("group_name", String(length=255, convert_unicode=False, assert_unicode=None), nullable=False, unique=True, default=None)
     group_parent_id = Column("group_parent_id", Integer(), ForeignKey('groups.group_id'), nullable=True, unique=None, default=None)
     group_description = Column("group_description", String(length=10000, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
 
     parent_group = relationship('Group', remote_side=group_id)
 
 
     def __init__(self, group_name='', parent_group=None):
         self.group_name = group_name
         self.parent_group = parent_group
 
     def __repr__(self):
         return "<%s('%s:%s')>" % (self.__class__.__name__, self.group_id,
                                   self.group_name)
 
     @classmethod
     def url_sep(cls):
         return '/'
 
     @property
     def parents(self):
         parents_recursion_limit = 5
         groups = []
         if self.parent_group is None:
             return groups
         cur_gr = self.parent_group
         groups.insert(0, cur_gr)
         cnt = 0
         while 1:
             cnt += 1
             gr = getattr(cur_gr, 'parent_group', None)
             cur_gr = cur_gr.parent_group
             if gr is None:
                 break
             if cnt == parents_recursion_limit:
                 # this will prevent accidental infinit loops
                 log.error('group nested more than %s' %
                           parents_recursion_limit)
                 break
 
             groups.insert(0, gr)
         return groups
 
     @property
     def children(self):
         return Session.query(Group).filter(Group.parent_group == self)
 
     @property
     def full_path(self):
         return Group.url_sep().join([g.group_name for g in self.parents] +
                         [self.group_name])
 
     @property
     def repositories(self):
         return Session.query(Repository).filter(Repository.group == self)
 
     @property
     def repositories_recursive_count(self):
         cnt = self.repositories.count()
 
         def children_count(group):
             cnt = 0
             for child in group.children:
                 cnt += child.repositories.count()
                 cnt += children_count(child)
             return cnt
 
         return cnt + children_count(self)
 
 class Permission(Base, BaseModel):
     __tablename__ = 'permissions'
     __table_args__ = {'extend_existing':True}
     permission_id = Column("permission_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     permission_name = Column("permission_name", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     permission_longname = Column("permission_longname", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
 
     def __repr__(self):
         return "<%s('%s:%s')>" % (self.__class__.__name__,
                                   self.permission_id, self.permission_name)
 
     @classmethod
     def get_by_key(cls, key):
         return Session.query(cls).filter(cls.permission_name == key).scalar()
 
 class RepoToPerm(Base, BaseModel):
     __tablename__ = 'repo_to_perm'
     __table_args__ = (UniqueConstraint('user_id', 'repository_id'), {'extend_existing':True})
     repo_to_perm_id = Column("repo_to_perm_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     user_id = Column("user_id", Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)
     permission_id = Column("permission_id", Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)
     repository_id = Column("repository_id", Integer(), ForeignKey('repositories.repo_id'), nullable=False, unique=None, default=None)
 
     user = relationship('User')
     permission = relationship('Permission')
     repository = relationship('Repository')
 
 class UserToPerm(Base, BaseModel):
     __tablename__ = 'user_to_perm'
     __table_args__ = (UniqueConstraint('user_id', 'permission_id'), {'extend_existing':True})
     user_to_perm_id = Column("user_to_perm_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     user_id = Column("user_id", Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)
     permission_id = Column("permission_id", Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)
 
     user = relationship('User')
     permission = relationship('Permission')
 
     @classmethod
     def has_perm(cls, user_id, perm):
         if not isinstance(perm, Permission):
             raise Exception('perm needs to be an instance of Permission class')
 
         return Session.query(cls).filter(cls.user_id == user_id)\
             .filter(cls.permission == perm).scalar() is not None
 
     @classmethod
     def grant_perm(cls, user_id, perm):
         if not isinstance(perm, Permission):
             raise Exception('perm needs to be an instance of Permission class')
 
         new = cls()
         new.user_id = user_id
         new.permission = perm
         try:
             Session.add(new)
             Session.commit()
         except:
             Session.rollback()
 
 
     @classmethod
     def revoke_perm(cls, user_id, perm):
         if not isinstance(perm, Permission):
             raise Exception('perm needs to be an instance of Permission class')
 
         try:
             Session.query(cls).filter(cls.user_id == user_id)\
                 .filter(cls.permission == perm).delete()
             Session.commit()
         except:
             Session.rollback()
 
 class UsersGroupRepoToPerm(Base, BaseModel):
     __tablename__ = 'users_group_repo_to_perm'
     __table_args__ = (UniqueConstraint('repository_id', 'users_group_id', 'permission_id'), {'extend_existing':True})
     users_group_to_perm_id = Column("users_group_to_perm_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     users_group_id = Column("users_group_id", Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)
     permission_id = Column("permission_id", Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)
     repository_id = Column("repository_id", Integer(), ForeignKey('repositories.repo_id'), nullable=False, unique=None, default=None)
 
     users_group = relationship('UsersGroup')
     permission = relationship('Permission')
     repository = relationship('Repository')
 
 
 class UsersGroupToPerm(Base, BaseModel):
     __tablename__ = 'users_group_to_perm'
     users_group_to_perm_id = Column("users_group_to_perm_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     users_group_id = Column("users_group_id", Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)
     permission_id = Column("permission_id", Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)
 
     users_group = relationship('UsersGroup')
     permission = relationship('Permission')
 
 
     @classmethod
     def has_perm(cls, users_group_id, perm):
         if not isinstance(perm, Permission):
             raise Exception('perm needs to be an instance of Permission class')
 
         return Session.query(cls).filter(cls.users_group_id ==
                                          users_group_id)\
                                          .filter(cls.permission == perm)\
                                          .scalar() is not None
 
     @classmethod
     def grant_perm(cls, users_group_id, perm):
         if not isinstance(perm, Permission):
             raise Exception('perm needs to be an instance of Permission class')
 
         new = cls()
         new.users_group_id = users_group_id
         new.permission = perm
         try:
             Session.add(new)
             Session.commit()
         except:
             Session.rollback()
 
 
     @classmethod
     def revoke_perm(cls, users_group_id, perm):
         if not isinstance(perm, Permission):
             raise Exception('perm needs to be an instance of Permission class')
 
         try:
             Session.query(cls).filter(cls.users_group_id == users_group_id)\
                 .filter(cls.permission == perm).delete()
             Session.commit()
         except:
             Session.rollback()
 
 
 class GroupToPerm(Base, BaseModel):
     __tablename__ = 'group_to_perm'
     __table_args__ = (UniqueConstraint('group_id', 'permission_id'), {'extend_existing':True})
 
     group_to_perm_id = Column("group_to_perm_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     user_id = Column("user_id", Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)
     permission_id = Column("permission_id", Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)
     group_id = Column("group_id", Integer(), ForeignKey('groups.group_id'), nullable=False, unique=None, default=None)
 
     user = relationship('User')
     permission = relationship('Permission')
     group = relationship('Group')
 
 class Statistics(Base, BaseModel):
     __tablename__ = 'statistics'
     __table_args__ = (UniqueConstraint('repository_id'), {'extend_existing':True})
     stat_id = Column("stat_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     repository_id = Column("repository_id", Integer(), ForeignKey('repositories.repo_id'), nullable=False, unique=True, default=None)
     stat_on_revision = Column("stat_on_revision", Integer(), nullable=False)
     commit_activity = Column("commit_activity", LargeBinary(1000000), nullable=False)#JSON data
     commit_activity_combined = Column("commit_activity_combined", LargeBinary(), nullable=False)#JSON data
     languages = Column("languages", LargeBinary(1000000), nullable=False)#JSON data
 
     repository = relationship('Repository', single_parent=True)
 
 class UserFollowing(Base, BaseModel):
     __tablename__ = 'user_followings'
     __table_args__ = (UniqueConstraint('user_id', 'follows_repository_id'),
                       UniqueConstraint('user_id', 'follows_user_id')
                       , {'extend_existing':True})
 
     user_following_id = Column("user_following_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     user_id = Column("user_id", Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)
     follows_repo_id = Column("follows_repository_id", Integer(), ForeignKey('repositories.repo_id'), nullable=True, unique=None, default=None)
     follows_user_id = Column("follows_user_id", Integer(), ForeignKey('users.user_id'), nullable=True, unique=None, default=None)
     follows_from = Column('follows_from', DateTime(timezone=False), nullable=True, unique=None, default=datetime.datetime.now)
 
     user = relationship('User', primaryjoin='User.user_id==UserFollowing.user_id')
 
     follows_user = relationship('User', primaryjoin='User.user_id==UserFollowing.follows_user_id')
     follows_repository = relationship('Repository', order_by='Repository.repo_name')
 
 
     @classmethod
     def get_repo_followers(cls, repo_id):
         return Session.query(cls).filter(cls.follows_repo_id == repo_id)
 
 class CacheInvalidation(Base, BaseModel):
     __tablename__ = 'cache_invalidation'
     __table_args__ = (UniqueConstraint('cache_key'), {'extend_existing':True})
     cache_id = Column("cache_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)
     cache_key = Column("cache_key", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     cache_args = Column("cache_args", String(length=255, convert_unicode=False, assert_unicode=None), nullable=True, unique=None, default=None)
     cache_active = Column("cache_active", Boolean(), nullable=True, unique=None, default=False)
 
 
     def __init__(self, cache_key, cache_args=''):
         self.cache_key = cache_key
         self.cache_args = cache_args
         self.cache_active = False
 
     def __repr__(self):
         return "<%s('%s:%s')>" % (self.__class__.__name__,
                                   self.cache_id, self.cache_key)
 
 class DbMigrateVersion(Base, BaseModel):
     __tablename__ = 'db_migrate_version'
     __table_args__ = {'extend_existing':True}
     repository_id = Column('repository_id', String(250), primary_key=True)
     repository_path = Column('repository_path', Text)
     version = Column('version', Integer)