wxWidgets/wxPython/samples/ide/activegrid/util/cachedloader.py
2005-04-08 22:54:02 +00:00

88 lines
2.5 KiB
Python

#----------------------------------------------------------------------------
# Name: cachedloader.py
# Purpose:
#
# Author: Joel Hare
#
# Created: 8/31/04
# CVS-ID: $Id$
# Copyright: (c) 2004-2005 ActiveGrid, Inc.
# License: wxWindows License
#----------------------------------------------------------------------------
import copy
import os.path
import string
import cStringIO
import time
# TODO: Instantiate the database and create a pool
class CachedLoader(object):
def __init__(self):
self.cache = {}
self.baseLoadDir = None
def fullPath(self, fileName):
if os.path.isabs(fileName):
absPath = fileName
elif self.baseLoadDir:
absPath = os.path.join(self.baseLoadDir, fileName)
else:
absPath = os.path.abspath(fileName)
return absPath
def setPrototype(self, fileName, loadedFile):
absPath = self.fullPath(fileName)
mtime = time.time() + 31536000.0 # Make sure prototypes aren't replaced by files on disk
self.cache[absPath] = (mtime, loadedFile)
def update(self, loader):
self.cache.update(loader.cache)
def clear(self):
self.cache.clear()
def delete(self, fileName):
absPath = self.fullPath(fileName)
del self.cache[absPath]
def needsLoad(self, fileName):
absPath = self.fullPath(fileName)
try:
cached = self.cache[absPath]
cachedTime = cached[0]
if cachedTime >= os.path.getmtime(absPath):
return False
except KeyError:
pass
return True
def load(self, fileName, loader):
absPath = self.fullPath(fileName)
loadedFile = None
try:
cached = self.cache[absPath]
except KeyError:
cached = None
if cached:
cachedTime = cached[0]
# ToDO We might need smarter logic for checking if a file needs to be reloaded
# ToDo We need a way to disable checking if this is a production server
if cachedTime >= os.path.getmtime(absPath):
loadedFile = cached[1]
if not loadedFile:
targetFile = file(absPath)
try:
mtime = os.path.getmtime(absPath)
loadedFile = loader(targetFile)
self.cache[absPath] = (mtime, loadedFile)
finally:
targetFile.close()
return loadedFile