X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=sfa%2Fstorage%2Falchemy.py;h=e9f96dd6875f42ea4962f8e36cfd63fdf51e41a8;hb=1cc8e9613cab8b5b22478de369f259e591c54e6d;hp=9e00e1bbbfa798c775c1dad215df668ab763d360;hpb=eb7d0272ff33c228dbb5d1207fbcb057f835d00b;p=sfa.git

diff --git a/sfa/storage/alchemy.py b/sfa/storage/alchemy.py
index 9e00e1bb..e9f96dd6 100644
--- a/sfa/storage/alchemy.py
+++ b/sfa/storage/alchemy.py
@@ -1,14 +1,15 @@
+from types import StringTypes
+
 from sqlalchemy import create_engine
 from sqlalchemy.orm import sessionmaker
 
-from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy import Column, Integer, String
-from sqlalchemy.orm import relationship, backref
 from sqlalchemy import ForeignKey
 
 from sfa.util.sfalogging import logger
 
-Base=declarative_base()
+# this module is designed to be loaded when the configured db server is reachable
+# OTOH model can be loaded from anywhere including the client-side
 
 class Alchemy:
 
@@ -23,21 +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):
@@ -46,15 +49,6 @@ class Alchemy:
     def check (self):
         self.engine.execute ("select 1").scalar()
 
-    # create schema
-    # warning: need to have all Base subclass loaded for this to work
-    def create_schema (self):
-        return Base.metadata.create_all(self.engine)
-
-    # does a complete wipe of the schema, use with care
-    def drop_schema (self):
-        return Base.metadata.drop_all(self.engine)
-
     def session (self):
         if self._session is None:
             Session=sessionmaker ()
@@ -66,67 +60,6 @@ class Alchemy:
         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()
-
-    def remove (self, record):
-        del record
-        self.commit()
-
-####################
-# dicts vs objects
-####################
-# historically the front end to the db dealt with dicts, so the code was only dealing with dicts
-# sqlalchemy however offers an object interface, meaning that you write obj.id instead of obj['id']
-# which is admittedly much nicer
-# however we still need to deal with dictionaries if only for the xmlrpc layer
-# 
-# here are a few utilities for this 
-# 
-# (*) first off, when an old pieve of code needs to be used as-is, if only temporarily, the simplest trick
-# is to use obj.__dict__
-# this behaves exactly like required, i.e. obj.__dict__['field']='new value' does change obj.field
-# however this depends on sqlalchemy's implementation so it should be avoided 
-#
-# (*) second, when an object needs to be exposed to the xmlrpc layer, we need to convert it into a dict
-# remember though that writing the resulting dictionary won't change the object
-# essentially obj.__dict__ would be fine too, except that we want to discard alchemy private keys starting with '_'
-# 2 ways are provided for that:
-# . dict(obj)
-# . obj.todict()
-# the former dict(obj) relies on __iter__() and next() below, and does not rely on the fields names
-# although it seems to work fine, I've found cases where it issues a weird python error that I could not get right
-# so the latter obj.todict() seems more reliable but more hacky as is relies on the form of fields, so this can probably be improved
-#
-# (*) finally for converting a dictionary into an sqlalchemy object, we provide
-# obj.set_from_dict(dict)
-
-from sqlalchemy.orm import object_mapper
-class AlchemyObj:
-    def __iter__(self): 
-        self._i = iter(object_mapper(self).columns)
-        return self 
-    def next(self): 
-        n = self._i.next().name
-        return n, getattr(self, n)
-    def todict (self):
-        d=self.__dict__
-        keys=[k for k in d.keys() if not k.startswith('_')]
-        return dict ( [ (k,d[k]) for k in keys ] )
-    def set_from_dict (self, d):
-        for (k,v) in d.iteritems():
-            setattr(self,k,v)
-
 ####################
 from sfa.util.config import Config