def __call__(self, cookie=None, **settings):
"""
Create a new session by calling a :cls:`sessionmaker` instance.
"""
if not hasattr(self, "settings"):
raise SessionConfigurationError("Session not configured yet.")
self._check_call_settings_sanity(settings)
all_settings = self.settings.copy()
# Add custom added params
if settings:
all_settings.update(settings)
# If requesting a different backend, give it
if 'backend' in settings:
session_class = get_session_class(settings['backend'])
else:
if not hasattr(self, 'session_class'):
raise SessionConfigurationError("No backend was configured")
session_class = self.session_class
# Delete the sessionmaker only settings
for sessionmaker_only in ["enable_encryption", "secret_file",
"backend"]:
if sessionmaker_only in all_settings:
del all_settings[sessionmaker_only]
# Create a new instance of a session
return session_class(cookie, **all_settings)
def configure(self, **settings):
"""
Configure sessions with default arguments. The settings passed in here
will be used for all newly created sessions, unless superseded by the
settings explicity passed to :meth:`sessionmaker.__call__`.
The following configuration settings are available exclusively to the
sessionmaker:
:param backend: The name of the backend to be used. This setting is
mandatory, but can also be passed individually on
session creation.
:param secret_file: If this is specified, a file is used to store keys
for both encryption and signing of the cookie.
This option conflicts with the ``signature_key``
and ``encryption_key`` options, so you can only use
one of them. Defaults to a file called `secret` in
the current working directory.
:param enable_encryption: Only useful in conjunction with
``secret_file``, as it specifies to not only
load a signature key but also an encryption
key. This requires `PyCrypto`_. Defaults to
no encryption.
.. _PyCrypto: https://www.dlitz.net/software/pycrypto/
"""
if hasattr(self, 'settings'):
raise SessionConfigurationError("Session already configured.")
self._check_settings_sanity(settings)
self._init_keys(settings)
assert 'signature_key' in settings
self.settings = settings
try:
backend = self.settings['backend']
self.session_class = get_session_class(backend)
except ValueError:
raise SessionConfigurationError("Backend %s not found." % backend)
except KeyError:
raise SessionConfigurationError("No backend given, please "
"specifiy a 'backend' setting.")
# Check if we can encrypt:
# This is just a failsafe check to throw up at configuration already
if 'encryption_key' in self.settings and not encryption_available():
raise CryptoError("Encryption not available, install pycrypto.")
