Add the 'pyramid-session-secret' option to all-in-one.conf
This value is used by pyramid_cubicweb to initialize the cookie factory.
from logilab.common.configuration import REQUIRED
import cubicweb.schema
cubicweb.schema.INTERNAL_TYPES.add('CWSession')
options = (
('pyramid-session-secret', {
'type': 'string',
'default': REQUIRED,
'help': 'Secret phrase to sign the session cookie',
'group': 'pyramid',
'level': 3
}),
)