diff options
Diffstat (limited to 'django/core/cache')
| -rw-r--r-- | django/core/cache/backends/filebased.py | 110 |
1 files changed, 74 insertions, 36 deletions
diff --git a/django/core/cache/backends/filebased.py b/django/core/cache/backends/filebased.py index 72cb877f6f..c1277bf20c 100644 --- a/django/core/cache/backends/filebased.py +++ b/django/core/cache/backends/filebased.py @@ -1,12 +1,12 @@ "File-based cache backend" +import md5 import os, time try: import cPickle as pickle except ImportError: import pickle from django.core.cache.backends.base import BaseCache -from django.utils.http import urlquote_plus class CacheClass(BaseCache): def __init__(self, dir, params): @@ -29,24 +29,10 @@ class CacheClass(BaseCache): self._createdir() def add(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) - if os.path.basename(fname) not in filelist: - try: - f = open(fname, 'wb') - now = time.time() - pickle.dump(now + timeout, f, 2) - pickle.dump(value, f, 2) - except (IOError, OSError): - pass + if self.has_key(key): + return None + + self.set(key, value, timeout) def get(self, key, default=None): fname = self._key_to_file(key) @@ -56,7 +42,7 @@ class CacheClass(BaseCache): now = time.time() if exp < now: f.close() - os.remove(fname) + self._delete(fname) else: return pickle.load(f) except (IOError, OSError, EOFError, pickle.PickleError): @@ -65,40 +51,74 @@ class CacheClass(BaseCache): def set(self, key, value, timeout=None): fname = self._key_to_file(key) + dirname = os.path.dirname(fname) + if timeout is None: timeout = self.default_timeout + + self._cull() + try: - filelist = os.listdir(self._dir) - except (IOError, OSError): - self._createdir() - filelist = [] - if len(filelist) > self._max_entries: - self._cull(filelist) - try: + if not os.path.exists(dirname): + os.makedirs(dirname) + f = open(fname, 'wb') now = time.time() - pickle.dump(now + timeout, f, 2) - pickle.dump(value, f, 2) + pickle.dump(now + timeout, f, pickle.HIGHEST_PROTOCOL) + pickle.dump(value, f, pickle.HIGHEST_PROTOCOL) except (IOError, OSError): pass def delete(self, key): try: - os.remove(self._key_to_file(key)) + self._delete(self._key_to_file(key)) + except (IOError, OSError): + pass + + def _delete(self, fname): + os.remove(fname) + try: + # Remove the 2 subdirs if they're empty + dirname = os.path.dirname(fname) + os.rmdir(dirname) + os.rmdir(os.path.dirname(dirname)) except (IOError, OSError): pass def has_key(self, key): - return os.path.exists(self._key_to_file(key)) + fname = self._key_to_file(key) + try: + f = open(fname, 'rb') + exp = pickle.load(f) + now = time.time() + if exp < now: + f.close() + self._delete(fname) + return False + else: + return True + except (IOError, OSError, EOFError, pickle.PickleError): + return False - def _cull(self, filelist): + def _cull(self): + if int(self._num_entries) < self._max_entries: + return + + try: + filelist = os.listdir(self._dir) + except (IOError, OSError): + return + 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: + doomed = [os.path.join(self._dir, k) for (i, k) in enumerate(filelist) if i % self._cull_frequency == 0] + + for topdir in doomed: try: - os.remove(os.path.join(self._dir, fname)) + for root, _, files in os.walk(topdir): + for f in files: + self._delete(os.path.join(root, f)) except (IOError, OSError): pass @@ -109,4 +129,22 @@ class CacheClass(BaseCache): 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, urlquote_plus(key)) + """ + Convert the filename into an md5 string. We'll turn the first couple + bits of the path into directory prefixes to be nice to filesystems + that have problems with large numbers of files in a directory. + + Thus, a cache key of "foo" gets turnned into a file named + ``{cache-dir}ac/bd/18db4cc2f85cedef654fccc4a4d8``. + """ + path = md5.new(key.encode('utf-8')).hexdigest() + path = os.path.join(path[:2], path[2:4], path[4:]) + return os.path.join(self._dir, path) + + def _get_num_entries(self): + count = 0 + for _,_,files in os.walk(self._dir): + count += len(files) + return count + _num_entries = property(_get_num_entries) + |