Cannot create a network topology other than very simple

[Akihiro Motoki]

In the current Quantum Router support in Horizon, when connecting a subnet to a router, a gateway IP address of the subnet is always used as an IP address of the router interface. This means that a subnet can connect to only a router and create a very limited topology.
A simple topology below cannot be created.

external network ---- router 1 ---- front net --- router2 ---- backend net

It can be easily addressed by adding IP address field in "Add Interface" form in Router Detail pane. IP address is optional and if IP address is specified, Horizon first creates a quantum port and then calls router-interface-add by passing port-id instead of subnet-id.

Since we have a nice topology view, if this issue has been addressed it must be valuable.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/23554

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/23554
Committed: http://github.com/openstack/horizon/commit/80f78f12e599a225dc8390f6beb4335217775597
Submitter: Jenkins
Branch: master

commit 80f78f12e599a225dc8390f6beb4335217775597
Author: Akihiro MOTOKI <email address hidden>
Date: Tue Mar 5 22:58:12 2013 +0900

    Allow users to create a rich network topology

    Fixes bug 1146926

    This commit enables Quantum Router support to create a router
    interface with a specified IP address. Previously we can connect
    one network (subnet) to only one router and a topology we can create
    is limited. By this commit we can connect one network to multiple
    routers and create a rich network topology through Dashboard.

    This commit also fixes the folowing bugs:
    * subnet_id in "Add Interface" form and network_id in "Set Gateway"
      form should be required=True since they are required fields.
    * An error message is display twice when the above two forms.

    Change-Id: Ifb90f70a4468fdf4e8ba356080cd0333f10e595f