Validate portgroup physical network consistency

When creating or updating a port that is a member of a portgroup, we
need to validate the consistency of the physical networks of the ports
in the portgroup.

There are 3 cases we are interested in:

- Creating a port which is a member of a portgroup.
- Updating the physical network of a port which is a member of a
  portgroup.
- Updating the portgroup of a port.

All ports in a portgroup should have the same value (which may be None)
for their physical_network field.

During creation or update of a port in a portgroup we apply the
following validation criteria:

- If the portgroup has existing ports with different physical networks,
  we raise PortgroupPhysnetInconsistent. This shouldn't ever happen.
- If the port has a physical network that is inconsistent with other
  ports in the portgroup, we raise exception.Conflict.

If a port's physical network is None, this indicates that ironic's VIF
attachment mapping algorithm should operate in a legacy (physical
network unaware) mode for this port or portgroup. This allows existing
ironic nodes to continue to function after an upgrade to a release
including physical network support.

Change-Id: I6a6d248155f98109dd36dba5837494f6974846e6
Partial-Bug: #1666009

1 files changed, 22 insertions, 0 deletions

diff --git a/ironic/common/network.py b/ironic/common/network.py
index 17d753be5..895ff8741 100644
--- a/ironic/common/network.py
+++ b/ironic/common/network.py
@@ -42,3 +42,25 @@ def get_node_vif_ids(task):
             port_vifs[port.uuid] = vif
     vifs['ports'] = port_vifs
     return vifs
+
+
+def get_portgroup_by_id(task, portgroup_id):
+    """Lookup a portgroup by ID on a task object.
+
+    :param task: a TaskManager instance
+    :param portgroup_id: ID of the portgroup.
+    :returns: A Portgroup object or None.
+    """
+    for portgroup in task.portgroups:
+        if portgroup.id == portgroup_id:
+            return portgroup
+
+
+def get_ports_by_portgroup_id(task, portgroup_id):
+    """Lookup ports by their portgroup ID on a task object.
+
+    :param task: a TaskManager instance
+    :param portgroup_id: ID of the portgroup.
+    :returns: A list of Port objects.
+    """
+    return [port for port in task.ports if port.portgroup_id == portgroup_id]