use session.delete(x) rather than del x

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

diff --git a/sfa/storage/alchemy.py b/sfa/storage/alchemy.py
index fce441b..ead5219 100644 (file)
--- a/sfa/storage/alchemy.py
+++ b/sfa/storage/alchemy.py
@@ -3,14 +3,14 @@ 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 persistentobjs can be loaded from anywhere including the client-side
 
 class Alchemy:
 
@@ -48,15 +48,6 @@ 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 ()
@@ -82,57 +73,9 @@ class Alchemy:
         self.commit()
 
     def remove (self, record):
-        del record
+        self.delete(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():
-            # experimental
-            if isinstance(v, StringTypes):
-                if v.lower() in ['true']: v=True
-                if v.lower() in ['false']: v=False
-            setattr(self,k,v)
-
 ####################
 from sfa.util.config import Config