[dbapi] makes anonymous_connection a computed property The current implementation is a boolean flag set manually by client code after connection creation. This led to different way to decide a anonymous_connection should be True (eg. different in the test than in the actual application code). It should not be client responsibility to set this flag. ``cnx.anonymous_connection`` is now a purely computed property. Connection with user in the "guests" group are anonymous, the other ain't. ``Session.anonymous_session`` is computed from ``cnx.anonymous_connection`` and get the updated behavior transparently. Closes #2953943

from logilab.common.shellutils import generate_password
from cubicweb.server.utils import crypt_password

for user in rql('CWUser U WHERE U cw_source S, S name "system", U upassword P, U login L').entities():
    salt = user.upassword.getvalue()
    if crypt_password('', salt) == salt:
        passwd = generate_password()
        print 'setting random password for user %s' % user.login
        user.set_attributes(upassword=passwd)

commit()