Scripts to run Shrinksafe during build.
The function that runs shrinksafe over JS files has been put
to a separate shell file to be run standalone without building
if needed.
import errno
import os
import tempfile
from django.conf import settings
from django.contrib.sessions.backends.base import SessionBase, CreateError
from django.core.exceptions import SuspiciousOperation, ImproperlyConfigured
class SessionStore(SessionBase):
"""
Implements a file based session store.
"""
def __init__(self, session_key=None):
self.storage_path = getattr(settings, "SESSION_FILE_PATH", None)
if not self.storage_path:
self.storage_path = tempfile.gettempdir()
# Make sure the storage path is valid.
if not os.path.isdir(self.storage_path):
raise ImproperlyConfigured(
"The session storage path %r doesn't exist. Please set your"
" SESSION_FILE_PATH setting to an existing directory in which"
" Django can store session data." % self.storage_path)
self.file_prefix = settings.SESSION_COOKIE_NAME
super(SessionStore, self).__init__(session_key)
def _key_to_file(self, session_key=None):
"""
Get the file associated with this session key.
"""
if session_key is None:
session_key = self.session_key
# Make sure we're not vulnerable to directory traversal. Session keys
# should always be md5s, so they should never contain directory
# components.
if os.path.sep in session_key:
raise SuspiciousOperation(
"Invalid characters (directory components) in session key")
return os.path.join(self.storage_path, self.file_prefix + session_key)
def load(self):
session_data = {}
try:
session_file = open(self._key_to_file(), "rb")
try:
file_data = session_file.read()
# Don't fail if there is no data in the session file.
# We may have opened the empty placeholder file.
if file_data:
try:
session_data = self.decode(file_data)
except (EOFError, SuspiciousOperation):
self.create()
finally:
session_file.close()
except IOError:
pass
return session_data
def create(self):
while True:
self._session_key = self._get_new_session_key()
try:
self.save(must_create=True)
except CreateError:
continue
self.modified = True
self._session_cache = {}
return
def save(self, must_create=False):
# Get the session data now, before we start messing
# with the file it is stored within.
session_data = self._get_session(no_load=must_create)
session_file_name = self._key_to_file()
try:
# Make sure the file exists. If it does not already exist, an
# empty placeholder file is created.
flags = os.O_WRONLY | os.O_CREAT | getattr(os, 'O_BINARY', 0)
if must_create:
flags |= os.O_EXCL
fd = os.open(session_file_name, flags)
os.close(fd)
except OSError, e:
if must_create and e.errno == errno.EEXIST:
raise CreateError
raise
# Write the session file without interfering with other threads
# or processes. By writing to an atomically generated temporary
# file and then using the atomic os.rename() to make the complete
# file visible, we avoid having to lock the session file, while
# still maintaining its integrity.
#
# Note: Locking the session file was explored, but rejected in part
# because in order to be atomic and cross-platform, it required a
# long-lived lock file for each session, doubling the number of
# files in the session storage directory at any given time. This
# rename solution is cleaner and avoids any additional overhead
# when reading the session data, which is the more common case
# unless SESSION_SAVE_EVERY_REQUEST = True.
#
# See ticket #8616.
dir, prefix = os.path.split(session_file_name)
try:
output_file_fd, output_file_name = tempfile.mkstemp(dir=dir,
prefix=prefix + '_out_')
renamed = False
try:
try:
os.write(output_file_fd, self.encode(session_data))
finally:
os.close(output_file_fd)
os.rename(output_file_name, session_file_name)
renamed = True
finally:
if not renamed:
os.unlink(output_file_name)
except (OSError, IOError, EOFError):
pass
def exists(self, session_key):
if os.path.exists(self._key_to_file(session_key)):
return True
return False
def delete(self, session_key=None):
if session_key is None:
if self._session_key is None:
return
session_key = self._session_key
try:
os.unlink(self._key_to_file(session_key))
except OSError:
pass
def clean(self):
pass