Big Update: Automatic updating, Show what albums/songs you already have, Config fixes, Fixed restart & shutdown buttons

mako/cache.py

@@ -0,0 +1,124 @@
+# mako/cache.py
+# Copyright (C) 2006-2011 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+from mako import exceptions
+
+cache = None
+
+class BeakerMissing(object):
+    def get_cache(self, name, **kwargs):
+        raise exceptions.RuntimeException("the Beaker package is required to use cache functionality.")
+
+class Cache(object):
+    """Represents a data content cache made available to the module
+    space of a :class:`.Template` object.
+ 
+    :class:`.Cache` is a wrapper on top of a Beaker CacheManager object.
+    This object in turn references any number of "containers", each of
+    which defines its own backend (i.e. file, memory, memcached, etc.) 
+    independently of the rest.
+ 
+    """
+ 
+    def __init__(self, id, starttime):
+        self.id = id
+        self.starttime = starttime
+        self.def_regions = {}
+ 
+    def put(self, key, value, **kwargs):
+        """Place a value in the cache.
+ 
+        :param key: the value's key.
+        :param value: the value
+        :param \**kwargs: cache configuration arguments.  The 
+         backend is configured using these arguments upon first request.
+         Subsequent requests that use the same series of configuration
+         values will use that same backend.
+ 
+        """
+ 
+        defname = kwargs.pop('defname', None)
+        expiretime = kwargs.pop('expiretime', None)
+        createfunc = kwargs.pop('createfunc', None)
+ 
+        self._get_cache(defname, **kwargs).put_value(key, starttime=self.starttime, expiretime=expiretime)
+ 
+    def get(self, key, **kwargs):
+        """Retrieve a value from the cache.
+ 
+        :param key: the value's key.
+        :param \**kwargs: cache configuration arguments.  The 
+         backend is configured using these arguments upon first request.
+         Subsequent requests that use the same series of configuration
+         values will use that same backend.
+ 
+        """
+ 
+        defname = kwargs.pop('defname', None)
+        expiretime = kwargs.pop('expiretime', None)
+        createfunc = kwargs.pop('createfunc', None)
+ 
+        return self._get_cache(defname, **kwargs).get_value(key, starttime=self.starttime, expiretime=expiretime, createfunc=createfunc)
+ 
+    def invalidate(self, key, **kwargs):
+        """Invalidate a value in the cache.
+ 
+        :param key: the value's key.
+        :param \**kwargs: cache configuration arguments.  The 
+         backend is configured using these arguments upon first request.
+         Subsequent requests that use the same series of configuration
+         values will use that same backend.
+ 
+        """
+        defname = kwargs.pop('defname', None)
+        expiretime = kwargs.pop('expiretime', None)
+        createfunc = kwargs.pop('createfunc', None)
+ 
+        self._get_cache(defname, **kwargs).remove_value(key, starttime=self.starttime, expiretime=expiretime)
+ 
+    def invalidate_body(self):
+        """Invalidate the cached content of the "body" method for this template.
+ 
+        """
+        self.invalidate('render_body', defname='render_body')
+ 
+    def invalidate_def(self, name):
+        """Invalidate the cached content of a particular <%def> within this template."""
+ 
+        self.invalidate('render_%s' % name, defname='render_%s' % name)
+ 
+    def invalidate_closure(self, name):
+        """Invalidate a nested <%def> within this template.
+ 
+        Caching of nested defs is a blunt tool as there is no
+        management of scope - nested defs that use cache tags
+        need to have names unique of all other nested defs in the 
+        template, else their content will be overwritten by 
+        each other.
+ 
+        """
+ 
+        self.invalidate(name, defname=name)
+ 
+    def _get_cache(self, defname, type=None, **kw):
+        global cache
+        if not cache:
+            try:
+                from beaker import cache as beaker_cache
+                cache = beaker_cache.CacheManager()
+            except ImportError:
+                # keep a fake cache around so subsequent 
+                # calls don't attempt to re-import
+                cache = BeakerMissing()
+
+        if type == 'memcached':
+            type = 'ext:memcached'
+        if not type:
+            (type, kw) = self.def_regions.get(defname, ('memory', {}))
+        else:
+            self.def_regions[defname] = (type, kw)
+        return cache.get_cache(self.id, type=type, **kw)
+