cromlech.wsgistate 0.3b2

Session handling for cromlech using wsgistate

cromlech.beaker is an integration of beaker to cromlech for session management.

Context manager

Let’s import some helpers:

>>> import pytest
>>> from webtest import TestApp
>>> SK = 'session.key'

And our session controller:

>>> from cromlech.wsgistate import WsgistateSession
>>> from cromlech.wsgistate.controlled import WsgistateSession

>>> def simple_app(environ, start_response):
...     """retained visited path, raise exception if path contain 'fail'
...     """
...     with WsgistateSession(environ, SK) as session:
...         path = environ['PATH_INFO']
...         history = session.setdefault('path', [])
...         history.append(path)
...         if path == '/fail':
...             raise ValueError
...     start_response('200 OK', [('Content-type', 'text/plain')])
...     return [', '.join(history)]

Then run it with wsgistate middelware:

>>> from cromlech.wsgistate import session_wrapper
>>> wsgi_app = TestApp(session_wrapper(simple_app, session_key=SK))
>>> result = wsgi_app.get('/foo')
>>> result.status
'200 OK'
>>> result.body
'/foo'

>>> result = wsgi_app.get('/bar')
>>> result.status
'200 OK'
>>> result.body
'/foo, /bar'

If application raise an exception, the context manager wont save the session:

>>> result = wsgi_app.get('/fail')
Traceback (most recent call last):
...
ValueError
>>> result.status
'200 OK'
>>> result.body
'/foo, /bar'

Testing the transaction awareness

>>> import transaction
>>> from cromlech.wsgistate import SessionStateException

>>> def transactional_app(environ, start_response):
...
...     with transaction.manager as tm:
...         with WsgistateSession(environ, SK, tm) as session:
...             session['crom'] = 'Pyramid'
...             tm.abort()
...
...     assert not session
...
...     with transaction.manager as tm:
...         with WsgistateSession(environ, SK, tm) as session:
...             session['crom'] = 'Crom'
...
...     with transaction.manager as tm:
...         with WsgistateSession(environ, SK, tm) as session:
...             session['lech'] = 'Lech'
...             sp1 = tm.savepoint()
...
...             session['crom'] = 'Zope'
...             session['lech'] = 'Quack'
...             sp2 = tm.savepoint()
...
...             session['crom'] = 'PHP'
...             sp3 = tm.savepoint()
...
...             sp2.rollback()
...             assert session['crom'] == 'Zope'
...             assert session['lech'] == 'Quack'
...
...             session['crom'] = 'Zorglub'
...             session['lech'] = 'Zimbabwe'
...
...             sp1.rollback()
...
...     # outside of a transaction, the writing is prohibited
...     with pytest.raises(SessionStateException) as e:
...         session['fail'] = True
...
...     assert e.value.message == (
...         "Session's current state disallows writing")
...
...     start_response('200 OK', [('Content-type', 'text/plain')])
...     return [session.get('crom', ''), session.get('lech', '')]

>>> wsgi_app = TestApp(session_wrapper(transactional_app, session_key=SK))
>>> result = wsgi_app.get('/bar')
>>> result.body
'CromLech'

Changelog

0.3b2 (2017-03-18)

• Added python3 compatibility

0.3b1 (2016-11-29)

• Added Timeout exception and bubbling up through the environ, to know when a session expired.

0.2 (2014-08-06)

• Forwarding the local_conf options to the decorator, for further configuration

0.1 (2013-03-13)

• Initial release