server/ovirtserver/model/__init__.py

   1 # Copyright (C) 2010, Red Hat, Inc.
   2 # Written by Darryl L. Pierce
   3 #
   4 # This program is free software; you can redistribute it and/or
   5 # modify it under the terms of the GNU General Public License
   6 # as published by the Free Software Foundation; either version 2
   7 # of the License, or (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program; if not, write to the Free Software
  16 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17
  18 """The application's model objects"""
  19
  20 from zope.sqlalchemy import ZopeTransactionExtension
  21 from sqlalchemy.orm import scoped_session, sessionmaker
  22 #from sqlalchemy import MetaData
  23 from sqlalchemy.ext.declarative import declarative_base
  24
  25 # Global session manager: DBSession() returns the Thread-local
  26 # session object appropriate for the current web request.
  27 maker = sessionmaker(autoflush=True, autocommit=False,
  28                      extension=ZopeTransactionExtension())
  29 DBSession = scoped_session(maker)
  30
  31 # Base class for all of our model classes: By default, the data model is
  32 # defined with SQLAlchemy's declarative extension, but if you need more
  33 # control, you can switch to the traditional method.
  34 DeclarativeBase = declarative_base()
  35
  36 # There are two convenient ways for you to spare some typing.
  37 # You can have a query property on all your model classes by doing this:
  38 # DeclarativeBase.query = DBSession.query_property()
  39 # Or you can use a session-aware mapper as it was used in TurboGears 1:
  40 # DeclarativeBase = declarative_base(mapper=DBSession.mapper)
  41
  42 # Global metadata.
  43 # The default metadata is the one from the declarative base.
  44 metadata = DeclarativeBase.metadata
  45
  46 # If you have multiple databases with overlapping table names, you'll need a
  47 # metadata for each database. Feel free to rename 'metadata2'.
  48 #metadata2 = MetaData()
  49
  50 #####
  51 # Generally you will not want to define your table's mappers, and data objects
  52 # here in __init__ but will want to create modules them in the model directory
  53 # and import them at the bottom of this file.
  54 #
  55 ######
  56
  57 def init_model(engine):
  58     """Call me before using any of the tables or classes in the model."""
  59
  60     DBSession.configure(bind=engine)
  61     # If you are using reflection to introspect your database and create
  62     # table objects for you, your tables must be defined and mapped inside
  63     # the init_model function, so that the engine is available if you
  64     # use the model outside tg2, you need to make sure this is called before
  65     # you use the model.
  66
  67     #
  68     # See the following example:
  69
  70     #global t_reflected
  71
  72     #t_reflected = Table("Reflected", metadata,
  73     #    autoload=True, autoload_with=engine)
  74
  75     #mapper(Reflected, t_reflected)
  76
  77 # Import your model modules here.