Inconsistent enable_snat management

[Cedric Brandily]

Neutron reset enable_snat on router-gateway-clear but not on router-gateway-set which implies inconsistent behavior:

# pub1, pub2 are external networks and router1 is a router

(neutron) router-gateway-set router1 pub1 --disable-snat
Set gateway for router router
(neutron) router-show router1 -c external_gateway_info
+-----------------------+------------------------------------------------------------------------------+
| Field | Value |
+-----------------------+------------------------------------------------------------------------------+
| external_gateway_info | {"network_id": "1682e4f4-7dc4-4ed0-bd10-e526ab2f6f81", "enable_snat": false} |
+-----------------------+------------------------------------------------------------------------------+
(neutron) router-gateway-clear router
Removed gateway from router router
(neutron) router-gateway-set router pub2
Set gateway for router router
(neutron) router-show router1 -c external_gateway_info
+-----------------------+------------------------------------------------------------------------------+
| Field | Value |
+-----------------------+------------------------------------------------------------------------------+
| external_gateway_info | {"network_id": "a32bcb44-165a-4de8-a8db-35f6ff8f2712", "enable_snat": true} |
+-----------------------+------------------------------------------------------------------------------+

==> enable_snat == False lost during router-gateway-clear

(neutron) router-gateway-set router1 pub1 --disable-snat
Set gateway for router router
(neutron) router-show router1 -c external_gateway_info
+-----------------------+------------------------------------------------------------------------------+
| Field | Value |
+-----------------------+------------------------------------------------------------------------------+
| external_gateway_info | {"network_id": "1682e4f4-7dc4-4ed0-bd10-e526ab2f6f81", "enable_snat": false} |
+-----------------------+------------------------------------------------------------------------------+
(neutron) router-gateway-set router pub2
Set gateway for router router
(neutron) router-show router1 -c external_gateway_info
+-----------------------+------------------------------------------------------------------------------+
| Field | Value |
+-----------------------+------------------------------------------------------------------------------+
| external_gateway_info | {"network_id": "a32bcb44-165a-4de8-a8db-35f6ff8f2712", "enable_snat": false} |
+-----------------------+------------------------------------------------------------------------------+

==> enable_snat == False not lost during router-gateway-set

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/130199

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/130199
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=ccd30a8cab6b91259cfb09b16a8fbbf69747cdf4
Submitter: Jenkins
Branch: master

commit ccd30a8cab6b91259cfb09b16a8fbbf69747cdf4
Author: Cedric Brandily <email address hidden>
Date: Wed Oct 22 14:03:13 2014 +0200

    Correct inconsistent enable_snat management

    Neutron resets enable_snat attribute when external_gateway_info is
    cleared but not when external_gateway_info is only updated which
    implies the following sets of actions have different behaviors:

      neutron router-gateway-set router1 pub1 --disable-snat
      neutron router-gateway-set router1 pub2

    enable_snat is False after the last command

      neutron router-gateway-set router1 pub1 --disable-snat
      neutron router-gateway-clear router1
      neutron router-gateway-set router1 pub2

    enable_snat is True after the 2nd command resets the gateway AND
    enable_snat.

    This change proposes to always reset the attribute enable_snat when
    enable_snat is not provided in external_gateway_info on POST/PUT for
    consistency.

    APIImpact
    Change-Id: Ibab289936c55b1cf9614b44a4f18f54c959ee9e8
    Closes-Bug: #1384146

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: neutron-pecan
Review: https://review.openstack.org/185072