--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/backend/sqlalchemy/Database.py	Sun Aug 21 03:55:16 2011 +0200
@@ -0,0 +1,36 @@
+
+from sqlalchemy.engine import create_engine
+from sqlalchemy.orm import sessionmaker
+import Mapping
+import sys
+import util
+
+# Keep the connection to the database only once. The feed updater and the GUI app will
+# operate on a single engine/session but this comes in handy for interactive use
+engine = None
+SessionMaker = None
+
+def createSession(databaseUrl=None):
+    if databaseUrl is None:
+        databaseUrl = _getDatabaseUrl()
+    initEngine(databaseUrl)
+    Mapping.createMapping(engine)
+    initSessionMaker()
+    return SessionMaker()
+
+def _getDatabaseUrl():
+    if len(sys.argv) < 2:
+        print("Usage: %s <database url>" % (sys.argv[0]))
+        sys.exit(1)
+    return sys.argv[1]
+
+def initEngine(databaseUrl):
+    global engine
+    if engine is None:
+        verbose = util.databaseLoggingEnabled()
+        engine = create_engine(databaseUrl, echo=verbose)
+
+def initSessionMaker():
+    global SessionMaker
+    if SessionMaker is None:
+        SessionMaker = sessionmaker(bind=engine)