Authentication cannot be scoped to multiple targets during hook-clear

[Joe D'Andrea]

In heat-newton, when trying to clear a pre-create hook for a floating IP resource, the following error is returned: "ERROR: HEAT-E99001 Service neutron is not available for resource type OS::Neutron::Port, reason: Authentication cannot be scoped to multiple targets. Pick one of: project, domain, trust or unscoped."

The OS_* environment variables appear correct, e.g.:

OS_AUTH_URL=http://controller:35357/v3
OS_IDENTITY_API_VERSION=3
OS_INSECURE=1
OS_PASSWORD=password
OS_PROJECT_DOMAIN_ID=default
OS_PROJECT_NAME=my_project
OS_REGION_NAME=RegionOne
OS_TENANT_NAME=my_project
OS_USERNAME=username
OS_USER_DOMAIN_ID=default

Heat environment contains the following in order to set the hook:

resource_registry:
  resources:
    "*_floating_ip":
      hooks: pre-create

Meanwhile, polling shows:

Resource Name: my_floating_ip
ID: abd58e48-1b05-4f77-84be-77d9c8b5aa03
Resource Status Reason: CREATE paused until Hook pre-create is cleared
Resource Status: INIT_COMPLETE

Then, to clear the hook:

# openstack stack hook clear my_stack my_floating_ip --pre-create
ERROR: HEAT-E99001 Service neutron is not available for resource type OS::Neutron::Port, reason: Authentication cannot be scoped to multiple targets. Pick one of: project, domain, trust or unscoped

Using the UUID results in no visible ERROR message, and the hook still isn't cleared.

Possibly related: https://bugs.launchpad.net/heat/+bug/1526293