[Yt-svn] yt-commit r1029 - in branches/yt-object-serialization/yt: fido lagos

[mturk at wrangler.dreamhost.com]

Author: mturk
Date: Tue Dec 23 15:57:19 2008
New Revision: 1029
URL: http://yt.spacepope.org/changeset/1029

Log:
Adding a non-functional SQLite backend for parameter file storage and also a
caching mechanism for existant parameter files.



Added:
   branches/yt-object-serialization/yt/fido/ParameterFileStorage.py
Modified:
   branches/yt-object-serialization/yt/lagos/OutputTypes.py

Added: branches/yt-object-serialization/yt/fido/ParameterFileStorage.py
==============================================================================
--- (empty file)
+++ branches/yt-object-serialization/yt/fido/ParameterFileStorage.py	Tue Dec 23 15:57:19 2008
@@ -0,0 +1,53 @@
+"""
+A simple SQLite interface to grabbing and storing parameter files
+
+Author: Matthew Turk <matthewturk at gmail.com>
+Affiliation: KIPAC/SLAC/Stanford
+Homepage: http://yt.enzotools.org/
+License:
+  Copyright (C) 2008 Matthew Turk.  All Rights Reserved.
+
+  This file is part of yt.
+
+  yt is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 3 of the License, or
+  (at your option) any later version.
+
+  This program 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 General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+## This is going to be the means of interacting with an SQLite (no, I repeat,
+## ORM will be used here!) db in the ~/.yt/ directory where parameter files
+## will be stored.  It will be queried for a hash, which then gets instantiated
+## and returned to the user.
+
+## Non-functional right now.
+
+from yt.fido import *
+import sqlite
+
+class ParameterFileStore(object):
+    _shared_state = {} # Do we need this?
+
+    def __new__(cls, *args, **kwargs):
+        pass
+        
+    def _get_db_name(self):
+        return os.path.expanduser("~/.yt/pfdb.sql")
+
+    def _initialize_new(self, filename = None):
+        self._conn = sqlite.connect(self._get_db_name())
+
+    def get_pf(self, hash):
+        pass
+
+    def check_pf(self, fn = None, ctid = None, basedir = None,
+                 initial_time = None, hash = None):
+        pass

Modified: branches/yt-object-serialization/yt/lagos/OutputTypes.py
==============================================================================
--- branches/yt-object-serialization/yt/lagos/OutputTypes.py	(original)
+++ branches/yt-object-serialization/yt/lagos/OutputTypes.py	Tue Dec 23 15:57:19 2008
@@ -32,7 +32,22 @@
 # When such a thing comes to pass, I'll move all the stuff that is contant up
 # to here, and then have it instantiate EnzoStaticOutputs as appropriate.
 
+_cached_pfs = defaultdict(lambda: dict())
+
 class StaticOutput(object):
+    class __metaclass__(type):
+        def __call__(cls, *args, **kwargs):
+            return cls.__new__(cls, *args, **kwargs)
+
+    def __new__(cls, filename, *args, **kwargs):
+        apath = os.path.abspath(filename)
+        if not os.path.exists(apath): raise IOError
+        if apath not in _cached_pfs:
+            obj = object.__new__(cls)
+            _cached_pfs[apath] = obj
+            obj.__init__(filename, *args, **kwargs)
+        return _cached_pfs.pop(apath)
+
     def __init__(self, filename, data_style=None):
         """
         Base class for generating new output types.  Principally consists of