Create subnet by domain

A cloud/domain admin should be able to create a subnet on any
project it is granted on.
This change adds the 'project' parameter that accepts either
a name (admin-only) or id.

lib/ansible/modules/cloud/openstack/os_subnet.py

@@ -105,6 +105,11 @@ options:
      choices: ['dhcpv6-stateful', 'dhcpv6-stateless', 'slaac']
      required: false
      default: None
+   project:
+     description:
+        - Project name or ID containing the subnet (name admin-only)
+     required: false
+     default: None
 requirements:
     - "python >= 2.6"
     - "shade"
@@ -233,6 +238,7 @@ def main():
         ipv6_ra_mode=dict(default=None, choice=ipv6_mode_choices),
         ipv6_address_mode=dict(default=None, choice=ipv6_mode_choices),
         state=dict(default='present', choices=['absent', 'present']),
+        project=dict(default=None)
     )
 
     module_kwargs = openstack_module_kwargs()
@@ -256,6 +262,7 @@ def main():
     host_routes = module.params['host_routes']
     ipv6_ra_mode = module.params['ipv6_ra_mode']
     ipv6_a_mode = module.params['ipv6_address_mode']
+    project = module.params.pop('project')
 
     # Check for required parameters when state == 'present'
     if state == 'present':
@@ -272,7 +279,17 @@ def main():
 
     try:
         cloud = shade.openstack_cloud(**module.params)
-        subnet = cloud.get_subnet(subnet_name)
+        if project is not None:
+            proj = cloud.get_project(project)
+            if proj is None:
+                module.fail_json(msg='Project %s could not be found' % project)
+            project_id = proj['id']
+            filters = {'tenant_id': project_id}
+        else:
+            project_id = None
+            filters = None
+
+        subnet = cloud.get_subnet(subnet_name, filters=filters)
 
         if module.check_mode:
             module.exit_json(changed=_system_state_change(module, subnet,
@@ -289,7 +306,8 @@ def main():
                                              allocation_pools=pool,
                                              host_routes=host_routes,
                                              ipv6_ra_mode=ipv6_ra_mode,
-                                             ipv6_address_mode=ipv6_a_mode)
+                                             ipv6_address_mode=ipv6_a_mode,
+                                             tenant_id=project_id)
                 changed = True
             else:
                 if _needs_update(subnet, module, cloud):