Major overhaul for standalone operation.

This removes some of the `edbob` reliance, as well as borrowing some templates
and styling etc. from Dtail.

tailbone/app.py

@@ -0,0 +1,81 @@
+#!/usr/bin/env python
+# -*- coding: utf-8  -*-
+################################################################################
+#
+#  Rattail -- Retail Software Framework
+#  Copyright © 2010-2012 Lance Edgar
+#
+#  This file is part of Rattail.
+#
+#  Rattail is free software: you can redistribute it and/or modify it under the
+#  terms of the GNU Affero General Public License as published by the Free
+#  Software Foundation, either version 3 of the License, or (at your option)
+#  any later version.
+#
+#  Rattail 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 Affero General Public License for
+#  more details.
+#
+#  You should have received a copy of the GNU Affero General Public License
+#  along with Rattail.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+
+"""
+Application Entry Point
+"""
+
+from pyramid.config import Configurator
+
+import os.path
+import edbob
+
+import edbob.db
+from .db import Session
+from zope.sqlalchemy import ZopeTransactionExtension
+
+from pyramid.authentication import SessionAuthenticationPolicy
+from .auth import TailboneAuthorizationPolicy
+
+
+def main(global_config, **settings):
+    """
+    This function returns a Pyramid WSGI application.
+    """
+
+    # Use Tailbone templates by default.
+    settings.setdefault('mako.directories', ['tailbone:templates'])
+
+    # Make two attempts when "retryable" errors happen during transactions.
+    # This is intended to gracefully handle database restarts.
+    settings.setdefault('tm.attempts', 2)
+
+    config = Configurator(settings=settings)
+
+    # Initialize edbob, dammit.
+    edbob.init('rattail', os.path.abspath(settings['edbob.config']))
+    edbob.init_modules(['edbob.time', 'edbob.db', 'rattail.db'])
+
+    # Configure the primary database session.  For now, this leverages edbob's
+    # initialization to define the engine connection.
+    assert edbob.db.engine
+    Session.configure(bind=edbob.db.engine)
+    Session.configure(extension=ZopeTransactionExtension())
+
+    # Configure user authentication / authorization.
+    config.set_authentication_policy(SessionAuthenticationPolicy())
+    config.set_authorization_policy(TailboneAuthorizationPolicy())
+
+    # Bring in some Pyramid goodies.
+    config.include('pyramid_beaker')
+    config.include('pyramid_tm')
+
+    # Bring in the rest of Tailbone.
+    config.include('tailbone')
+
+    # Consider PostgreSQL server restart errors to be "retryable."
+    config.add_tween('edbob.pyramid.tweens.sqlerror_tween_factory',
+                     under='pyramid_tm.tm_tween_factory')
+
+    return config.make_wsgi_app()