magic-removal: Merged to [2387]
git-svn-id: http://code.djangoproject.com/svn/django/branches/magic-removal@2388 bcc190cf-cafb-0310-a4f2-bffc1f526a37
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@ -16,7 +16,7 @@ your computer is "internal").</p>
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{% endblocktrans %}
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{% endblocktrans %}
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<div id="content-main">
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<div id="content-main">
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<h3><a href="javascript:(function(){if(typeof ActiveXObject!='undefined'){x=new ActiveXObject('Microsoft.XMLHTTP')}else if(typeof XMLHttpRequest!='undefined'){x=new XMLHttpRequest()}else{return;}x.open('HEAD',location.href,false);x.send(null);try{view=x.getResponseHeader('x-view');}catch(e){alert('No view found for this page');return;}if(view=="undefined"){alert("No view found for this page");}document.location='{{ admin_url }}doc/views/'+view+'/';})()">{% trans "Documentation for this page" %}</a></h3>
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<h3><a href="javascript:(function(){if(typeof ActiveXObject!='undefined'){x=new ActiveXObject('Microsoft.XMLHTTP')}else if(typeof XMLHttpRequest!='undefined'){x=new XMLHttpRequest()}else{return;}x.open('HEAD',location.href,false);x.send(null);try{view=x.getResponseHeader('x-view');}catch(e){alert('No view found for this page');return;}if(view=='undefined'){alert('No view found for this page');}document.location='{{ admin_url }}doc/views/'+view+'/';})()">{% trans "Documentation for this page" %}</a></h3>
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<p>{% trans "Jumps you from any page to the documentation for the view that generates that page." %}</p>
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<p>{% trans "Jumps you from any page to the documentation for the view that generates that page." %}</p>
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<h3><a href="javascript:(function(){if(typeof ActiveXObject!='undefined'){x=new ActiveXObject('Microsoft.XMLHTTP')}else if(typeof XMLHttpRequest!='undefined'){x=new XMLHttpRequest()}else{return;}x.open('GET',location.href,false);x.send(null);try{type=x.getResponseHeader('x-object-type');id=x.getResponseHeader('x-object-id');}catch(e){type='(none)';id='(none)';}d=document;b=d.body;e=d.createElement('div');e.id='xxxhhh';s=e.style;s.position='absolute';s.left='10px';s.top='10px';s.font='10px monospace';s.border='1px black solid';s.padding='4px';s.backgroundColor='#eee';e.appendChild(d.createTextNode('Type: '+type));e.appendChild(d.createElement('br'));e.appendChild(d.createTextNode('ID: '+id));e.appendChild(d.createElement('br'));l=d.createElement('a');l.href='#';l.onclick=function(){b.removeChild(e);};l.appendChild(d.createTextNode('[close]'));l.style.textDecoration='none';e.appendChild(l);b.appendChild(e);})();">{% trans "Show object ID" %}</a></h3>
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<h3><a href="javascript:(function(){if(typeof ActiveXObject!='undefined'){x=new ActiveXObject('Microsoft.XMLHTTP')}else if(typeof XMLHttpRequest!='undefined'){x=new XMLHttpRequest()}else{return;}x.open('GET',location.href,false);x.send(null);try{type=x.getResponseHeader('x-object-type');id=x.getResponseHeader('x-object-id');}catch(e){type='(none)';id='(none)';}d=document;b=d.body;e=d.createElement('div');e.id='xxxhhh';s=e.style;s.position='absolute';s.left='10px';s.top='10px';s.font='10px monospace';s.border='1px black solid';s.padding='4px';s.backgroundColor='#eee';e.appendChild(d.createTextNode('Type: '+type));e.appendChild(d.createElement('br'));e.appendChild(d.createTextNode('ID: '+id));e.appendChild(d.createElement('br'));l=d.createElement('a');l.href='#';l.onclick=function(){b.removeChild(e);};l.appendChild(d.createTextNode('[close]'));l.style.textDecoration='none';e.appendChild(l);b.appendChild(e);})();">{% trans "Show object ID" %}</a></h3>
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@ -1,502 +0,0 @@
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"""
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Caching framework.
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This module defines set of cache backends that all conform to a simple API.
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In a nutshell, a cache is a set of values -- which can be any object that
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may be pickled -- identified by string keys. For the complete API, see
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the abstract Cache object, below.
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Client code should not access a cache backend directly; instead
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it should use the get_cache() function. This function will look at
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settings.CACHE_BACKEND and use that to create and load a cache object.
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The CACHE_BACKEND setting is a quasi-URI; examples are:
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memcached://127.0.0.1:11211/ A memcached backend; the server is running
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on localhost port 11211. You can use
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multiple memcached servers by separating
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them with semicolons.
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db://tablename/ A database backend in a table named
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"tablename". This table should be created
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with "django-admin createcachetable".
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file:///var/tmp/django_cache/ A file-based cache stored in the directory
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/var/tmp/django_cache/.
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simple:/// A simple single-process memory cache; you
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probably don't want to use this except for
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testing. Note that this cache backend is
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NOT threadsafe!
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locmem:/// A more sophisticated local memory cache;
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this is multi-process- and thread-safe.
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dummy:/// Doesn't actually cache. For use in test
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environments.
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All caches may take arguments; these are given in query-string style. Valid
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arguments are:
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timeout
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Default timeout, in seconds, to use for the cache. Defaults
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to 5 minutes (300 seconds).
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max_entries
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For the simple, file, and database backends, the maximum number of
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entries allowed in the cache before it is cleaned. Defaults to
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300.
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cull_percentage
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The percentage of entries that are culled when max_entries is reached.
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The actual percentage is 1/cull_percentage, so set cull_percentage=3 to
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cull 1/3 of the entries when max_entries is reached.
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A value of 0 for cull_percentage means that the entire cache will be
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dumped when max_entries is reached. This makes culling *much* faster
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at the expense of more cache misses.
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For example:
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memcached://127.0.0.1:11211/?timeout=60
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db://tablename/?timeout=120&max_entries=500&cull_percentage=4
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Invalid arguments are silently ignored, as are invalid values of known
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arguments.
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"""
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##############
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# Exceptions #
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##############
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class InvalidCacheBackendError(Exception):
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pass
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################################
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# Abstract base implementation #
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################################
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class _Cache:
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def __init__(self, params):
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timeout = params.get('timeout', 300)
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try:
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timeout = int(timeout)
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except (ValueError, TypeError):
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timeout = 300
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self.default_timeout = timeout
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def get(self, key, default=None):
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'''
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Fetch a given key from the cache. If the key does not exist, return
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default, which itself defaults to None.
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'''
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raise NotImplementedError
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def set(self, key, value, timeout=None):
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'''
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Set a value in the cache. If timeout is given, that timeout will be
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used for the key; otherwise the default cache timeout will be used.
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'''
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raise NotImplementedError
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def delete(self, key):
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'''
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Delete a key from the cache, failing silently.
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'''
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raise NotImplementedError
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def get_many(self, keys):
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'''
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Fetch a bunch of keys from the cache. For certain backends (memcached,
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pgsql) this can be *much* faster when fetching multiple values.
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Returns a dict mapping each key in keys to its value. If the given
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key is missing, it will be missing from the response dict.
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'''
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d = {}
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for k in keys:
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val = self.get(k)
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if val is not None:
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d[k] = val
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return d
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def has_key(self, key):
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'''
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Returns True if the key is in the cache and has not expired.
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'''
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return self.get(key) is not None
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###########################
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# memcached cache backend #
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###########################
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try:
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import memcache
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except ImportError:
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_MemcachedCache = None
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else:
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class _MemcachedCache(_Cache):
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"Memcached cache backend."
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def __init__(self, server, params):
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_Cache.__init__(self, params)
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self._cache = memcache.Client(server.split(';'))
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def get(self, key, default=None):
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val = self._cache.get(key)
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if val is None:
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return default
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else:
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return val
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def set(self, key, value, timeout=0):
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self._cache.set(key, value, timeout)
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def delete(self, key):
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self._cache.delete(key)
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def get_many(self, keys):
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return self._cache.get_multi(keys)
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##################################
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# Single-process in-memory cache #
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##################################
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import time
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class _SimpleCache(_Cache):
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"Simple single-process in-memory cache."
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def __init__(self, host, params):
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_Cache.__init__(self, params)
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self._cache = {}
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self._expire_info = {}
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max_entries = params.get('max_entries', 300)
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try:
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self._max_entries = int(max_entries)
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except (ValueError, TypeError):
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self._max_entries = 300
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cull_frequency = params.get('cull_frequency', 3)
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try:
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self._cull_frequency = int(cull_frequency)
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except (ValueError, TypeError):
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self._cull_frequency = 3
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def get(self, key, default=None):
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now = time.time()
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exp = self._expire_info.get(key)
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if exp is None:
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return default
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elif exp < now:
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del self._cache[key]
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del self._expire_info[key]
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return default
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else:
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return self._cache[key]
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def set(self, key, value, timeout=None):
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if len(self._cache) >= self._max_entries:
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self._cull()
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if timeout is None:
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timeout = self.default_timeout
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self._cache[key] = value
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self._expire_info[key] = time.time() + timeout
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def delete(self, key):
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try:
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del self._cache[key]
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except KeyError:
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pass
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try:
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del self._expire_info[key]
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except KeyError:
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pass
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def has_key(self, key):
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return self._cache.has_key(key)
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def _cull(self):
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if self._cull_frequency == 0:
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self._cache.clear()
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self._expire_info.clear()
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else:
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doomed = [k for (i, k) in enumerate(self._cache) if i % self._cull_frequency == 0]
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for k in doomed:
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self.delete(k)
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###############################
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# Thread-safe in-memory cache #
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###############################
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try:
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import cPickle as pickle
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except ImportError:
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import pickle
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import copy
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from django.utils.synch import RWLock
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class _LocMemCache(_SimpleCache):
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"Thread-safe in-memory cache."
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def __init__(self, host, params):
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_SimpleCache.__init__(self, host, params)
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self._lock = RWLock()
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def get(self, key, default=None):
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should_delete = False
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self._lock.reader_enters()
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try:
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now = time.time()
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exp = self._expire_info.get(key)
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if exp is None:
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return default
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elif exp < now:
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should_delete = True
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else:
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return copy.deepcopy(self._cache[key])
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finally:
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self._lock.reader_leaves()
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if should_delete:
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self._lock.writer_enters()
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try:
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del self._cache[key]
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del self._expire_info[key]
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return default
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finally:
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self._lock.writer_leaves()
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def set(self, key, value, timeout=None):
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self._lock.writer_enters()
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try:
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_SimpleCache.set(self, key, value, timeout)
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finally:
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self._lock.writer_leaves()
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def delete(self, key):
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self._lock.writer_enters()
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try:
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_SimpleCache.delete(self, key)
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finally:
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self._lock.writer_leaves()
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###############
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# Dummy cache #
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###############
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class _DummyCache(_Cache):
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def __init__(self, *args, **kwargs):
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pass
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def get(self, *args, **kwargs):
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pass
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def set(self, *args, **kwargs):
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pass
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def delete(self, *args, **kwargs):
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pass
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def get_many(self, *args, **kwargs):
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pass
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def has_key(self, *args, **kwargs):
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return False
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####################
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# File-based cache #
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####################
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import os
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import urllib
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|
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class _FileCache(_SimpleCache):
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"File-based cache."
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def __init__(self, dir, params):
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self._dir = dir
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if not os.path.exists(self._dir):
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self._createdir()
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_SimpleCache.__init__(self, dir, params)
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del self._cache
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del self._expire_info
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def get(self, key, default=None):
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fname = self._key_to_file(key)
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try:
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f = open(fname, 'rb')
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exp = pickle.load(f)
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now = time.time()
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if exp < now:
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f.close()
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os.remove(fname)
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else:
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return pickle.load(f)
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except (IOError, OSError, EOFError, pickle.PickleError):
|
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pass
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return default
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|
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def set(self, key, value, timeout=None):
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fname = self._key_to_file(key)
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if timeout is None:
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timeout = self.default_timeout
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try:
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filelist = os.listdir(self._dir)
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except (IOError, OSError):
|
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self._createdir()
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filelist = []
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if len(filelist) > self._max_entries:
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self._cull(filelist)
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try:
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f = open(fname, 'wb')
|
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now = time.time()
|
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pickle.dump(now + timeout, f, 2)
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|
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pickle.dump(value, f, 2)
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|
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except (IOError, OSError):
|
|
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pass
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|
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def delete(self, key):
|
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try:
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os.remove(self._key_to_file(key))
|
|
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except (IOError, OSError):
|
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pass
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|
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def has_key(self, key):
|
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return os.path.exists(self._key_to_file(key))
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|
||||||
|
|
||||||
def _cull(self, filelist):
|
|
||||||
if self._cull_frequency == 0:
|
|
||||||
doomed = filelist
|
|
||||||
else:
|
|
||||||
doomed = [k for (i, k) in enumerate(filelist) if i % self._cull_frequency == 0]
|
|
||||||
for fname in doomed:
|
|
||||||
try:
|
|
||||||
os.remove(os.path.join(self._dir, fname))
|
|
||||||
except (IOError, OSError):
|
|
||||||
pass
|
|
||||||
|
|
||||||
def _createdir(self):
|
|
||||||
try:
|
|
||||||
os.makedirs(self._dir)
|
|
||||||
except OSError:
|
|
||||||
raise EnvironmentError, "Cache directory '%s' does not exist and could not be created'" % self._dir
|
|
||||||
|
|
||||||
def _key_to_file(self, key):
|
|
||||||
return os.path.join(self._dir, urllib.quote_plus(key))
|
|
||||||
|
|
||||||
#############
|
|
||||||
# SQL cache #
|
|
||||||
#############
|
|
||||||
|
|
||||||
import base64
|
|
||||||
from django.db import connection, DatabaseError
|
|
||||||
from datetime import datetime
|
|
||||||
|
|
||||||
class _DBCache(_Cache):
|
|
||||||
"SQL cache backend."
|
|
||||||
def __init__(self, table, params):
|
|
||||||
_Cache.__init__(self, params)
|
|
||||||
self._table = table
|
|
||||||
max_entries = params.get('max_entries', 300)
|
|
||||||
try:
|
|
||||||
self._max_entries = int(max_entries)
|
|
||||||
except (ValueError, TypeError):
|
|
||||||
self._max_entries = 300
|
|
||||||
cull_frequency = params.get('cull_frequency', 3)
|
|
||||||
try:
|
|
||||||
self._cull_frequency = int(cull_frequency)
|
|
||||||
except (ValueError, TypeError):
|
|
||||||
self._cull_frequency = 3
|
|
||||||
|
|
||||||
def get(self, key, default=None):
|
|
||||||
cursor = connection.cursor()
|
|
||||||
cursor.execute("SELECT cache_key, value, expires FROM %s WHERE cache_key = %%s" % self._table, [key])
|
|
||||||
row = cursor.fetchone()
|
|
||||||
if row is None:
|
|
||||||
return default
|
|
||||||
now = datetime.now()
|
|
||||||
if row[2] < now:
|
|
||||||
cursor.execute("DELETE FROM %s WHERE cache_key = %%s" % self._table, [key])
|
|
||||||
connection.commit()
|
|
||||||
return default
|
|
||||||
return pickle.loads(base64.decodestring(row[1]))
|
|
||||||
|
|
||||||
def set(self, key, value, timeout=None):
|
|
||||||
if timeout is None:
|
|
||||||
timeout = self.default_timeout
|
|
||||||
cursor = connection.cursor()
|
|
||||||
cursor.execute("SELECT COUNT(*) FROM %s" % self._table)
|
|
||||||
num = cursor.fetchone()[0]
|
|
||||||
now = datetime.now().replace(microsecond=0)
|
|
||||||
exp = datetime.fromtimestamp(time.time() + timeout).replace(microsecond=0)
|
|
||||||
if num > self._max_entries:
|
|
||||||
self._cull(cursor, now)
|
|
||||||
encoded = base64.encodestring(pickle.dumps(value, 2)).strip()
|
|
||||||
cursor.execute("SELECT cache_key FROM %s WHERE cache_key = %%s" % self._table, [key])
|
|
||||||
try:
|
|
||||||
if cursor.fetchone():
|
|
||||||
cursor.execute("UPDATE %s SET value = %%s, expires = %%s WHERE cache_key = %%s" % self._table, [encoded, str(exp), key])
|
|
||||||
else:
|
|
||||||
cursor.execute("INSERT INTO %s (cache_key, value, expires) VALUES (%%s, %%s, %%s)" % self._table, [key, encoded, str(exp)])
|
|
||||||
except DatabaseError:
|
|
||||||
# To be threadsafe, updates/inserts are allowed to fail silently
|
|
||||||
pass
|
|
||||||
else:
|
|
||||||
connection.commit()
|
|
||||||
|
|
||||||
def delete(self, key):
|
|
||||||
cursor = connection.cursor()
|
|
||||||
cursor.execute("DELETE FROM %s WHERE cache_key = %%s" % self._table, [key])
|
|
||||||
connection.commit()
|
|
||||||
|
|
||||||
def has_key(self, key):
|
|
||||||
cursor = connection.cursor()
|
|
||||||
cursor.execute("SELECT cache_key FROM %s WHERE cache_key = %%s" % self._table, [key])
|
|
||||||
return cursor.fetchone() is not None
|
|
||||||
|
|
||||||
def _cull(self, cursor, now):
|
|
||||||
if self._cull_frequency == 0:
|
|
||||||
cursor.execute("DELETE FROM %s" % self._table)
|
|
||||||
else:
|
|
||||||
cursor.execute("DELETE FROM %s WHERE expires < %%s" % self._table, [str(now)])
|
|
||||||
cursor.execute("SELECT COUNT(*) FROM %s" % self._table)
|
|
||||||
num = cursor.fetchone()[0]
|
|
||||||
if num > self._max_entries:
|
|
||||||
cursor.execute("SELECT cache_key FROM %s ORDER BY cache_key LIMIT 1 OFFSET %%s" % self._table, [num / self._cull_frequency])
|
|
||||||
cursor.execute("DELETE FROM %s WHERE cache_key < %%s" % self._table, [cursor.fetchone()[0]])
|
|
||||||
|
|
||||||
##########################################
|
|
||||||
# Read settings and load a cache backend #
|
|
||||||
##########################################
|
|
||||||
|
|
||||||
from cgi import parse_qsl
|
|
||||||
|
|
||||||
_BACKENDS = {
|
|
||||||
'memcached': _MemcachedCache,
|
|
||||||
'simple': _SimpleCache,
|
|
||||||
'locmem': _LocMemCache,
|
|
||||||
'file': _FileCache,
|
|
||||||
'db': _DBCache,
|
|
||||||
'dummy': _DummyCache,
|
|
||||||
}
|
|
||||||
|
|
||||||
def get_cache(backend_uri):
|
|
||||||
if backend_uri.find(':') == -1:
|
|
||||||
raise InvalidCacheBackendError("Backend URI must start with scheme://")
|
|
||||||
scheme, rest = backend_uri.split(':', 1)
|
|
||||||
if not rest.startswith('//'):
|
|
||||||
raise InvalidCacheBackendError("Backend URI must start with scheme://")
|
|
||||||
if scheme not in _BACKENDS.keys():
|
|
||||||
raise InvalidCacheBackendError("%r is not a valid cache backend" % scheme)
|
|
||||||
|
|
||||||
host = rest[2:]
|
|
||||||
qpos = rest.find('?')
|
|
||||||
if qpos != -1:
|
|
||||||
params = dict(parse_qsl(rest[qpos+1:]))
|
|
||||||
host = rest[2:qpos]
|
|
||||||
else:
|
|
||||||
params = {}
|
|
||||||
if host.endswith('/'):
|
|
||||||
host = host[:-1]
|
|
||||||
|
|
||||||
return _BACKENDS[scheme](host, params)
|
|
||||||
|
|
||||||
from django.conf import settings
|
|
||||||
cache = get_cache(settings.CACHE_BACKEND)
|
|
|
@ -0,0 +1,54 @@
|
||||||
|
"""
|
||||||
|
Caching framework.
|
||||||
|
|
||||||
|
This package defines set of cache backends that all conform to a simple API.
|
||||||
|
In a nutshell, a cache is a set of values -- which can be any object that
|
||||||
|
may be pickled -- identified by string keys. For the complete API, see
|
||||||
|
the abstract BaseCache class in django.core.cache.backends.base.
|
||||||
|
|
||||||
|
Client code should not access a cache backend directly; instead it should
|
||||||
|
either use the "cache" variable made available here, or it should use the
|
||||||
|
get_cache() function made available here. get_cache() takes a backend URI
|
||||||
|
(e.g. "memcached://127.0.0.1:11211/") and returns an instance of a backend
|
||||||
|
cache class.
|
||||||
|
|
||||||
|
See docs/cache.txt for information on the public API.
|
||||||
|
"""
|
||||||
|
|
||||||
|
from cgi import parse_qsl
|
||||||
|
from django.conf import settings
|
||||||
|
from django.core.cache.backends.base import InvalidCacheBackendError
|
||||||
|
|
||||||
|
BACKENDS = {
|
||||||
|
# name for use in settings file --> name of module in "backends" directory
|
||||||
|
'memcached': 'memcached',
|
||||||
|
'simple': 'simple',
|
||||||
|
'locmem': 'locmem',
|
||||||
|
'file': 'filebased',
|
||||||
|
'db': 'db',
|
||||||
|
'dummy': 'dummy',
|
||||||
|
}
|
||||||
|
|
||||||
|
def get_cache(backend_uri):
|
||||||
|
if backend_uri.find(':') == -1:
|
||||||
|
raise InvalidCacheBackendError, "Backend URI must start with scheme://"
|
||||||
|
scheme, rest = backend_uri.split(':', 1)
|
||||||
|
if not rest.startswith('//'):
|
||||||
|
raise InvalidCacheBackendError, "Backend URI must start with scheme://"
|
||||||
|
if scheme not in BACKENDS:
|
||||||
|
raise InvalidCacheBackendError, "%r is not a valid cache backend" % scheme
|
||||||
|
|
||||||
|
host = rest[2:]
|
||||||
|
qpos = rest.find('?')
|
||||||
|
if qpos != -1:
|
||||||
|
params = dict(parse_qsl(rest[qpos+1:]))
|
||||||
|
host = rest[2:qpos]
|
||||||
|
else:
|
||||||
|
params = {}
|
||||||
|
if host.endswith('/'):
|
||||||
|
host = host[:-1]
|
||||||
|
|
||||||
|
cache_class = getattr(__import__('django.core.cache.backends.%s' % BACKENDS[scheme], '', '', ['']), 'CacheClass')
|
||||||
|
return cache_class(host, params)
|
||||||
|
|
||||||
|
cache = get_cache(settings.CACHE_BACKEND)
|
|
@ -0,0 +1,56 @@
|
||||||
|
"Base Cache class."
|
||||||
|
|
||||||
|
from django.core.exceptions import ImproperlyConfigured
|
||||||
|
|
||||||
|
class InvalidCacheBackendError(ImproperlyConfigured):
|
||||||
|
pass
|
||||||
|
|
||||||
|
class BaseCache:
|
||||||
|
def __init__(self, params):
|
||||||
|
timeout = params.get('timeout', 300)
|
||||||
|
try:
|
||||||
|
timeout = int(timeout)
|
||||||
|
except (ValueError, TypeError):
|
||||||
|
timeout = 300
|
||||||
|
self.default_timeout = timeout
|
||||||
|
|
||||||
|
def get(self, key, default=None):
|
||||||
|
"""
|
||||||
|
Fetch a given key from the cache. If the key does not exist, return
|
||||||
|
default, which itself defaults to None.
|
||||||
|
"""
|
||||||
|
raise NotImplementedError
|
||||||
|
|
||||||
|
def set(self, key, value, timeout=None):
|
||||||
|
"""
|
||||||
|
Set a value in the cache. If timeout is given, that timeout will be
|
||||||
|
used for the key; otherwise the default cache timeout will be used.
|
||||||
|
"""
|
||||||
|
raise NotImplementedError
|
||||||
|
|
||||||
|
def delete(self, key):
|
||||||
|
"""
|
||||||
|
Delete a key from the cache, failing silently.
|
||||||
|
"""
|
||||||
|
raise NotImplementedError
|
||||||
|
|
||||||
|
def get_many(self, keys):
|
||||||
|
"""
|
||||||
|
Fetch a bunch of keys from the cache. For certain backends (memcached,
|
||||||
|
pgsql) this can be *much* faster when fetching multiple values.
|
||||||
|
|
||||||
|
Returns a dict mapping each key in keys to its value. If the given
|
||||||
|
key is missing, it will be missing from the response dict.
|
||||||
|
"""
|
||||||
|
d = {}
|
||||||
|
for k in keys:
|
||||||
|
val = self.get(k)
|
||||||
|
if val is not None:
|
||||||
|
d[k] = val
|
||||||
|
return d
|
||||||
|
|
||||||
|
def has_key(self, key):
|
||||||
|
"""
|
||||||
|
Returns True if the key is in the cache and has not expired.
|
||||||
|
"""
|
||||||
|
return self.get(key) is not None
|
|
@ -0,0 +1,82 @@
|
||||||
|
"Database cache backend."
|
||||||
|
|
||||||
|
from django.core.cache.backends.base import BaseCache
|
||||||
|
from django.db import connection
|
||||||
|
import base64, time
|
||||||
|
from datetime import datetime
|
||||||
|
try:
|
||||||
|
import cPickle as pickle
|
||||||
|
except ImportError:
|
||||||
|
import pickle
|
||||||
|
|
||||||
|
class CacheClass(BaseCache):
|
||||||
|
def __init__(self, table, params):
|
||||||
|
BaseCache.__init__(self, params)
|
||||||
|
self._table = table
|
||||||
|
max_entries = params.get('max_entries', 300)
|
||||||
|
try:
|
||||||
|
self._max_entries = int(max_entries)
|
||||||
|
except (ValueError, TypeError):
|
||||||
|
self._max_entries = 300
|
||||||
|
cull_frequency = params.get('cull_frequency', 3)
|
||||||
|
try:
|
||||||
|
self._cull_frequency = int(cull_frequency)
|
||||||
|
except (ValueError, TypeError):
|
||||||
|
self._cull_frequency = 3
|
||||||
|
|
||||||
|
def get(self, key, default=None):
|
||||||
|
cursor = connection.cursor()
|
||||||
|
cursor.execute("SELECT cache_key, value, expires FROM %s WHERE cache_key = %%s" % self._table, [key])
|
||||||
|
row = cursor.fetchone()
|
||||||
|
if row is None:
|
||||||
|
return default
|
||||||
|
now = datetime.now()
|
||||||
|
if row[2] < now:
|
||||||
|
cursor.execute("DELETE FROM %s WHERE cache_key = %%s" % self._table, [key])
|
||||||
|
connection.commit()
|
||||||
|
return default
|
||||||
|
return pickle.loads(base64.decodestring(row[1]))
|
||||||
|
|
||||||
|
def set(self, key, value, timeout=None):
|
||||||
|
if timeout is None:
|
||||||
|
timeout = self.default_timeout
|
||||||
|
cursor = connection.cursor()
|
||||||
|
cursor.execute("SELECT COUNT(*) FROM %s" % self._table)
|
||||||
|
num = cursor.fetchone()[0]
|
||||||
|
now = datetime.now().replace(microsecond=0)
|
||||||
|
exp = datetime.fromtimestamp(time.time() + timeout).replace(microsecond=0)
|
||||||
|
if num > self._max_entries:
|
||||||
|
self._cull(cursor, now)
|
||||||
|
encoded = base64.encodestring(pickle.dumps(value, 2)).strip()
|
||||||
|
cursor.execute("SELECT cache_key FROM %s WHERE cache_key = %%s" % self._table, [key])
|
||||||
|
try:
|
||||||
|
if cursor.fetchone():
|
||||||
|
cursor.execute("UPDATE %s SET value = %%s, expires = %%s WHERE cache_key = %%s" % self._table, [encoded, str(exp), key])
|
||||||
|
else:
|
||||||
|
cursor.execute("INSERT INTO %s (cache_key, value, expires) VALUES (%%s, %%s, %%s)" % self._table, [key, encoded, str(exp)])
|
||||||
|
except DatabaseError:
|
||||||
|
# To be threadsafe, updates/inserts are allowed to fail silently
|
||||||
|
pass
|
||||||
|
else:
|
||||||
|
connection.commit()
|
||||||
|
|
||||||
|
def delete(self, key):
|
||||||
|
cursor = connection.cursor()
|
||||||
|
cursor.execute("DELETE FROM %s WHERE cache_key = %%s" % self._table, [key])
|
||||||
|
connection.commit()
|
||||||
|
|
||||||
|
def has_key(self, key):
|
||||||
|
cursor = connection.cursor()
|
||||||
|
cursor.execute("SELECT cache_key FROM %s WHERE cache_key = %%s" % self._table, [key])
|
||||||
|
return cursor.fetchone() is not None
|
||||||
|
|
||||||
|
def _cull(self, cursor, now):
|
||||||
|
if self._cull_frequency == 0:
|
||||||
|
cursor.execute("DELETE FROM %s" % self._table)
|
||||||
|
else:
|
||||||
|
cursor.execute("DELETE FROM %s WHERE expires < %%s" % self._table, [str(now)])
|
||||||
|
cursor.execute("SELECT COUNT(*) FROM %s" % self._table)
|
||||||
|
num = cursor.fetchone()[0]
|
||||||
|
if num > self._max_entries:
|
||||||
|
cursor.execute("SELECT cache_key FROM %s ORDER BY cache_key LIMIT 1 OFFSET %%s" % self._table, [num / self._cull_frequency])
|
||||||
|
cursor.execute("DELETE FROM %s WHERE cache_key < %%s" % self._table, [cursor.fetchone()[0]])
|
|
@ -0,0 +1,22 @@
|
||||||
|
"Dummy cache backend"
|
||||||
|
|
||||||
|
from django.core.cache.backends.base import BaseCache
|
||||||
|
|
||||||
|
class CacheClass(BaseCache):
|
||||||
|
def __init__(self, *args, **kwargs):
|
||||||
|
pass
|
||||||
|
|
||||||
|
def get(self, *args, **kwargs):
|
||||||
|
pass
|
||||||
|
|
||||||
|
def set(self, *args, **kwargs):
|
||||||
|
pass
|
||||||
|
|
||||||
|
def delete(self, *args, **kwargs):
|
||||||
|
pass
|
||||||
|
|
||||||
|
def get_many(self, *args, **kwargs):
|
||||||
|
pass
|
||||||
|
|
||||||
|
def has_key(self, *args, **kwargs):
|
||||||
|
return False
|
|
@ -0,0 +1,80 @@
|
||||||
|
"File-based cache backend"
|
||||||
|
|
||||||
|
from django.core.cache.backends.simple import CacheClass as SimpleCacheClass
|
||||||
|
import os, time, urllib
|
||||||
|
try:
|
||||||
|
import cPickle as pickle
|
||||||
|
except ImportError:
|
||||||
|
import pickle
|
||||||
|
|
||||||
|
class CacheClass(SimpleCacheClass):
|
||||||
|
def __init__(self, dir, params):
|
||||||
|
self._dir = dir
|
||||||
|
if not os.path.exists(self._dir):
|
||||||
|
self._createdir()
|
||||||
|
SimpleCacheClass.__init__(self, dir, params)
|
||||||
|
del self._cache
|
||||||
|
del self._expire_info
|
||||||
|
|
||||||
|
def get(self, key, default=None):
|
||||||
|
fname = self._key_to_file(key)
|
||||||
|
try:
|
||||||
|
f = open(fname, 'rb')
|
||||||
|
exp = pickle.load(f)
|
||||||
|
now = time.time()
|
||||||
|
if exp < now:
|
||||||
|
f.close()
|
||||||
|
os.remove(fname)
|
||||||
|
else:
|
||||||
|
return pickle.load(f)
|
||||||
|
except (IOError, OSError, EOFError, pickle.PickleError):
|
||||||
|
pass
|
||||||
|
return default
|
||||||
|
|
||||||
|
def set(self, key, value, timeout=None):
|
||||||
|
fname = self._key_to_file(key)
|
||||||
|
if timeout is None:
|
||||||
|
timeout = self.default_timeout
|
||||||
|
try:
|
||||||
|
filelist = os.listdir(self._dir)
|
||||||
|
except (IOError, OSError):
|
||||||
|
self._createdir()
|
||||||
|
filelist = []
|
||||||
|
if len(filelist) > self._max_entries:
|
||||||
|
self._cull(filelist)
|
||||||
|
try:
|
||||||
|
f = open(fname, 'wb')
|
||||||
|
now = time.time()
|
||||||
|
pickle.dump(now + timeout, f, 2)
|
||||||
|
pickle.dump(value, f, 2)
|
||||||
|
except (IOError, OSError):
|
||||||
|
pass
|
||||||
|
|
||||||
|
def delete(self, key):
|
||||||
|
try:
|
||||||
|
os.remove(self._key_to_file(key))
|
||||||
|
except (IOError, OSError):
|
||||||
|
pass
|
||||||
|
|
||||||
|
def has_key(self, key):
|
||||||
|
return os.path.exists(self._key_to_file(key))
|
||||||
|
|
||||||
|
def _cull(self, filelist):
|
||||||
|
if self._cull_frequency == 0:
|
||||||
|
doomed = filelist
|
||||||
|
else:
|
||||||
|
doomed = [k for (i, k) in enumerate(filelist) if i % self._cull_frequency == 0]
|
||||||
|
for fname in doomed:
|
||||||
|
try:
|
||||||
|
os.remove(os.path.join(self._dir, fname))
|
||||||
|
except (IOError, OSError):
|
||||||
|
pass
|
||||||
|
|
||||||
|
def _createdir(self):
|
||||||
|
try:
|
||||||
|
os.makedirs(self._dir)
|
||||||
|
except OSError:
|
||||||
|
raise EnvironmentError, "Cache directory '%s' does not exist and could not be created'" % self._dir
|
||||||
|
|
||||||
|
def _key_to_file(self, key):
|
||||||
|
return os.path.join(self._dir, urllib.quote_plus(key))
|
|
@ -0,0 +1,51 @@
|
||||||
|
"Thread-safe in-memory cache backend."
|
||||||
|
|
||||||
|
from django.core.cache.backends.simple import CacheClass as SimpleCacheClass
|
||||||
|
from django.utils.synch import RWLock
|
||||||
|
import copy, time
|
||||||
|
try:
|
||||||
|
import cPickle as pickle
|
||||||
|
except ImportError:
|
||||||
|
import pickle
|
||||||
|
|
||||||
|
class CacheClass(SimpleCacheClass):
|
||||||
|
def __init__(self, host, params):
|
||||||
|
SimpleCacheClass.__init__(self, host, params)
|
||||||
|
self._lock = RWLock()
|
||||||
|
|
||||||
|
def get(self, key, default=None):
|
||||||
|
should_delete = False
|
||||||
|
self._lock.reader_enters()
|
||||||
|
try:
|
||||||
|
now = time.time()
|
||||||
|
exp = self._expire_info.get(key)
|
||||||
|
if exp is None:
|
||||||
|
return default
|
||||||
|
elif exp < now:
|
||||||
|
should_delete = True
|
||||||
|
else:
|
||||||
|
return copy.deepcopy(self._cache[key])
|
||||||
|
finally:
|
||||||
|
self._lock.reader_leaves()
|
||||||
|
if should_delete:
|
||||||
|
self._lock.writer_enters()
|
||||||
|
try:
|
||||||
|
del self._cache[key]
|
||||||
|
del self._expire_info[key]
|
||||||
|
return default
|
||||||
|
finally:
|
||||||
|
self._lock.writer_leaves()
|
||||||
|
|
||||||
|
def set(self, key, value, timeout=None):
|
||||||
|
self._lock.writer_enters()
|
||||||
|
try:
|
||||||
|
SimpleCacheClass.set(self, key, value, timeout)
|
||||||
|
finally:
|
||||||
|
self._lock.writer_leaves()
|
||||||
|
|
||||||
|
def delete(self, key):
|
||||||
|
self._lock.writer_enters()
|
||||||
|
try:
|
||||||
|
SimpleCacheClass.delete(self, key)
|
||||||
|
finally:
|
||||||
|
self._lock.writer_leaves()
|
|
@ -0,0 +1,29 @@
|
||||||
|
"Memcached cache backend"
|
||||||
|
|
||||||
|
from django.core.cache.backends.base import BaseCache, InvalidCacheBackendError
|
||||||
|
|
||||||
|
try:
|
||||||
|
import memcache
|
||||||
|
except ImportError:
|
||||||
|
raise InvalidCacheBackendError, "Memcached cache backend requires the 'memcache' library"
|
||||||
|
|
||||||
|
class CacheClass(BaseCache):
|
||||||
|
def __init__(self, server, params):
|
||||||
|
BaseCache.__init__(self, params)
|
||||||
|
self._cache = memcache.Client(server.split(';'))
|
||||||
|
|
||||||
|
def get(self, key, default=None):
|
||||||
|
val = self._cache.get(key)
|
||||||
|
if val is None:
|
||||||
|
return default
|
||||||
|
else:
|
||||||
|
return val
|
||||||
|
|
||||||
|
def set(self, key, value, timeout=0):
|
||||||
|
self._cache.set(key, value, timeout)
|
||||||
|
|
||||||
|
def delete(self, key):
|
||||||
|
self._cache.delete(key)
|
||||||
|
|
||||||
|
def get_many(self, keys):
|
||||||
|
return self._cache.get_multi(keys)
|
|
@ -0,0 +1,64 @@
|
||||||
|
"Single-process in-memory cache backend."
|
||||||
|
|
||||||
|
from django.core.cache.backends.base import BaseCache
|
||||||
|
import time
|
||||||
|
|
||||||
|
class CacheClass(BaseCache):
|
||||||
|
def __init__(self, host, params):
|
||||||
|
BaseCache.__init__(self, params)
|
||||||
|
self._cache = {}
|
||||||
|
self._expire_info = {}
|
||||||
|
|
||||||
|
max_entries = params.get('max_entries', 300)
|
||||||
|
try:
|
||||||
|
self._max_entries = int(max_entries)
|
||||||
|
except (ValueError, TypeError):
|
||||||
|
self._max_entries = 300
|
||||||
|
|
||||||
|
cull_frequency = params.get('cull_frequency', 3)
|
||||||
|
try:
|
||||||
|
self._cull_frequency = int(cull_frequency)
|
||||||
|
except (ValueError, TypeError):
|
||||||
|
self._cull_frequency = 3
|
||||||
|
|
||||||
|
def get(self, key, default=None):
|
||||||
|
now = time.time()
|
||||||
|
exp = self._expire_info.get(key)
|
||||||
|
if exp is None:
|
||||||
|
return default
|
||||||
|
elif exp < now:
|
||||||
|
del self._cache[key]
|
||||||
|
del self._expire_info[key]
|
||||||
|
return default
|
||||||
|
else:
|
||||||
|
return self._cache[key]
|
||||||
|
|
||||||
|
def set(self, key, value, timeout=None):
|
||||||
|
if len(self._cache) >= self._max_entries:
|
||||||
|
self._cull()
|
||||||
|
if timeout is None:
|
||||||
|
timeout = self.default_timeout
|
||||||
|
self._cache[key] = value
|
||||||
|
self._expire_info[key] = time.time() + timeout
|
||||||
|
|
||||||
|
def delete(self, key):
|
||||||
|
try:
|
||||||
|
del self._cache[key]
|
||||||
|
except KeyError:
|
||||||
|
pass
|
||||||
|
try:
|
||||||
|
del self._expire_info[key]
|
||||||
|
except KeyError:
|
||||||
|
pass
|
||||||
|
|
||||||
|
def has_key(self, key):
|
||||||
|
return self._cache.has_key(key)
|
||||||
|
|
||||||
|
def _cull(self):
|
||||||
|
if self._cull_frequency == 0:
|
||||||
|
self._cache.clear()
|
||||||
|
self._expire_info.clear()
|
||||||
|
else:
|
||||||
|
doomed = [k for (i, k) in enumerate(self._cache) if i % self._cull_frequency == 0]
|
||||||
|
for k in doomed:
|
||||||
|
self.delete(k)
|
|
@ -16,6 +16,9 @@ def timesince(d, now=None):
|
||||||
(60 * 60, lambda n: ngettext('hour', 'hours', n)),
|
(60 * 60, lambda n: ngettext('hour', 'hours', n)),
|
||||||
(60, lambda n: ngettext('minute', 'minutes', n))
|
(60, lambda n: ngettext('minute', 'minutes', n))
|
||||||
)
|
)
|
||||||
|
# Convert datetime.date to datetime.datetime for comparison
|
||||||
|
if d.__class__ is not datetime.datetime:
|
||||||
|
d = datetime.datetime(d.year, d.month, d.day)
|
||||||
if now:
|
if now:
|
||||||
t = now.timetuple()
|
t = now.timetuple()
|
||||||
else:
|
else:
|
||||||
|
|
|
@ -33,6 +33,9 @@ Examples:
|
||||||
multiple memcached servers by separating
|
multiple memcached servers by separating
|
||||||
them with semicolons.
|
them with semicolons.
|
||||||
|
|
||||||
|
This backend requires the
|
||||||
|
`Python memcached bindings`_.
|
||||||
|
|
||||||
db://tablename/ A database backend in a table named
|
db://tablename/ A database backend in a table named
|
||||||
"tablename". This table should be created
|
"tablename". This table should be created
|
||||||
with "django-admin createcachetable".
|
with "django-admin createcachetable".
|
||||||
|
@ -82,6 +85,7 @@ Invalid arguments are silently ignored, as are invalid values of known
|
||||||
arguments.
|
arguments.
|
||||||
|
|
||||||
.. _memcached: http://www.danga.com/memcached/
|
.. _memcached: http://www.danga.com/memcached/
|
||||||
|
.. _Python memcached bindings: ftp://ftp.tummy.com/pub/python-memcached/
|
||||||
|
|
||||||
The per-site cache
|
The per-site cache
|
||||||
==================
|
==================
|
||||||
|
|
|
@ -237,6 +237,10 @@ False
|
||||||
>>> timesince(datetime.datetime.now() - datetime.timedelta(1))
|
>>> timesince(datetime.datetime.now() - datetime.timedelta(1))
|
||||||
'1 day'
|
'1 day'
|
||||||
|
|
||||||
|
# datetime.date compataibility with timesince
|
||||||
|
>>> timesince(datetime.date.today() - datetime.timedelta(1))
|
||||||
|
'1 day, 23 hours'
|
||||||
|
|
||||||
>>> default("val", "default")
|
>>> default("val", "default")
|
||||||
'val'
|
'val'
|
||||||
|
|
||||||
|
|
Loading…
Reference in New Issue