2to3 -f raise

[sfa.git] / sfa / storage / alchemy.py

diff --git a/sfa/storage/alchemy.py b/sfa/storage/alchemy.py
index ead5219..fb8dfac 100644 (file)
--- a/sfa/storage/alchemy.py
+++ b/sfa/storage/alchemy.py
@@ -4,18 +4,17 @@ from sqlalchemy import create_engine
 from sqlalchemy.orm import sessionmaker
 
 from sqlalchemy import Column, Integer, String
-from sqlalchemy.orm import relationship, backref
 from sqlalchemy import ForeignKey
 
 from sfa.util.sfalogging import logger
 
 # this module is designed to be loaded when the configured db server is reachable
-# OTOH persistentobjs can be loaded from anywhere including the client-side
+# OTOH model can be loaded from anywhere including the client-side
 
 class Alchemy:
 
     def __init__ (self, config):
-        dbname="sfa"
+        dbname = "sfa"
         # will be created lazily on-demand
         self._session = None
         # the former PostgreSQL.py used the psycopg2 directly and was doing
@@ -25,21 +24,23 @@ class Alchemy:
         # we indeed have /var/lib/pgsql/data/postgresql.conf where
         # this setting is unset, it might be an angle to tweak that if need be
         # try a unix socket first - omitting the hostname does the trick
-        unix_desc = "postgresql+psycopg2://%s:%s@:%s/%s"%\
+        unix_url = "postgresql+psycopg2://%s:%s@:%s/%s"%\
             (config.SFA_DB_USER,config.SFA_DB_PASSWORD,config.SFA_DB_PORT,dbname)
         # the TCP fallback method
-        tcp_desc = "postgresql+psycopg2://%s:%s@%s:%s/%s"%\
+        tcp_url = "postgresql+psycopg2://%s:%s@%s:%s/%s"%\
             (config.SFA_DB_USER,config.SFA_DB_PASSWORD,config.SFA_DB_HOST,config.SFA_DB_PORT,dbname)
-        for engine_desc in [ unix_desc, tcp_desc ] :
+        for url in [ unix_url, tcp_url ] :
             try:
-                self.engine = create_engine (engine_desc)
+                logger.debug("Trying db URL %s"%url)
+                self.engine = create_engine (url)
                 self.check()
+                self.url=url
                 return
             except:
                 pass
         self.engine=None
-        raise Exception,"Could not connect to database"
-                
+        raise Exception("Could not connect to database %s as %s with psycopg2"%(dbname,config.SFA_DB_USER))
+
 
     # expects boolean True: debug is ON or False: debug is OFF
     def debug (self, echo):
@@ -48,38 +49,34 @@ class Alchemy:
     def check (self):
         self.engine.execute ("select 1").scalar()
 
-    def session (self):
+    def global_session (self):
         if self._session is None:
             Session=sessionmaker ()
             self._session=Session(bind=self.engine)
+            logger.debug('alchemy.global_session created session %s'%self._session)
         return self._session
 
-    def close_session (self):
+    def close_global_session (self):
         if self._session is None: return
+        logger.debug('alchemy.close_global_session %s'%self._session)
         self._session.close()
         self._session=None
 
-    def commit (self):
-        self.session().commit()
-            
-    def insert (self, stuff, commit=False):
-        if isinstance (stuff,list):
-            self.session().add_all(stuff)
-        else:
-            self.session().add(obj)
-
-    # for compat with the previous PostgreSQL stuff
-    def update (self, record):
-        self.commit()
+    # create a dbsession to be managed separately
+    def session (self):
+        Session=sessionmaker()
+        session=Session (bind=self.engine)
+        logger.debug('alchemy.session created session %s'%session)
+        return session
 
-    def remove (self, record):
-        self.delete(record)
-        self.commit()
+    def close_session (self, session):
+        logger.debug('alchemy.close_session closed session %s'%session)
+        session.close()
 
 ####################
 from sfa.util.config import Config
 
 alchemy=Alchemy (Config())
 engine=alchemy.engine
-dbsession=alchemy.session()
+global_dbsession=alchemy.global_session()