Ryu 4.2 appears broken with python 3, lock Ryu version at 4.0

[Ryan Tidwell]

Just saw a gate failure in neutron-dynamic-routing where the python34 check job fails with the following error http://paste.openstack.org/show/497444/. The gate job ran against Ryu 4.2 and failed, but the check job ran against Ryu 4.0. It appears a recent change in Ryu (https://github.com/osrg/ryu/commit/7d42aecb8d6b4e91e4704fabb1d9eca1d873c148) failed to add an implementation of __hash__() in the class RouteFamily to go along with an implementation of __eq__(). If we cap Ryu at version 4.0 while a fix is made to Ryu we don't have this problem. Neutron currently specifies the Ryu version as ryu>=3.30.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/317860

[Armando Migliaccio (armando-migliaccio)]

This is not strictly speaking a Neutron issue.

[Armando Migliaccio (armando-migliaccio)]

Ryu's fix:

https://github.com/osrg/ryu/commit/a20b9e1fcd675e593c8b4cb383f28f404ff62add

[OpenStack Infra (hudson-openstack)]

Change abandoned by Ryan Tidwell (<email address hidden>) on branch: master
Review: https://review.openstack.org/317860

[IWAMOTO Toshihiro (iwamoto)]

Ryu 4.2.1 is out with the fix mentioned in the comment #3.