Actually delete registry settings on VM deletion

- since the `human_readable_vm_name` feature, the key under which
  information are stored in the registry, is not necessarily the
  VM name
- this was not considered in `delete_vm`

[#144344945](https://www.pivotaltracker.com/story/show/144344945)

src/bosh_openstack_cpi/lib/cloud/openstack/cloud.rb

@@ -328,8 +328,9 @@ def delete_vm(server_id)
             catch_error('Removing ports') { NetworkConfigurator.cleanup_ports(@openstack, server_port_ids) },
             catch_error('Removing lbaas pool memberships') { LoadbalancerConfigurator.new(@openstack, @logger).cleanup_memberships(server_tags) },
             catch_error('Deleting registry settings') {
-              @logger.info("Deleting settings for server `#{server.id}'...")
-              @registry.delete_settings(server.name)
+              registry_key = registry_key_for(server)
+              @logger.info("Deleting settings for server `#{server.id}' with registry_key `#{registry_key}' ...")
+              @registry.delete_settings(registry_key)
             })
         else
           @logger.info("Server `#{server_id}' not found. Skipping.")
@@ -677,8 +678,7 @@ def is_v3
     # @param [Fog::Compute::OpenStack::Server] server OpenStack server
     def update_agent_settings(server)
       raise ArgumentError, 'Block is not provided' unless block_given?
-      registry_key_metadatum = server.metadata.get(REGISTRY_KEY_TAG)
-      registry_key = registry_key_metadatum ? registry_key_metadatum.value : server.name
+      registry_key = registry_key_for(server)
       @logger.info("Updating settings for server `#{server.id}' with registry key `#{registry_key}'...")
       settings = @registry.read_settings(registry_key)
       yield settings
@@ -693,6 +693,11 @@ def info
 
     private
 
+    def registry_key_for(server)
+      registry_key_metadatum = server.metadata.get(REGISTRY_KEY_TAG)
+      registry_key_metadatum ? registry_key_metadatum.value : server.name
+    end
+
     def not_existing_net_ids(nics)
       result = []
       begin

src/bosh_openstack_cpi/spec/unit/delete_vm_spec.rb

@@ -2,10 +2,13 @@
 
 describe Bosh::OpenStackCloud::Cloud do
 
+  let(:registry_key) { 'vm-registry-key' }
+
   let(:server_metadata) do
     [
       double('metadatum', :key => 'lbaas_pool_0', :value => 'pool-id-0/membership-id-0'),
-      double('metadatum', :key => 'job', :value => 'bosh')
+      double('metadatum', :key => 'job', :value => 'bosh'),
+      double('metadatum', key: :registry_key, value: registry_key)
     ]
   end
 
@@ -26,6 +29,9 @@
      allow(server).to receive(:destroy)
      allow(cloud.openstack).to receive(:wait_resource)
      allow(@registry).to receive(:delete_settings)
+     allow(server_metadata).to receive(:get) { |param|
+       server_metadata.find { |metadatum| metadatum.key == param}
+     }
      allow(Bosh::OpenStackCloud::LoadbalancerConfigurator).to receive(:new).and_return(loadbalancer_configurator)
      allow(loadbalancer_configurator).to receive(:cleanup_memberships)
    end
@@ -68,11 +74,12 @@
     expect(server).to have_received(:destroy)
     expect(cloud.openstack).to have_received(:wait_resource).with(server, [:terminated, :deleted], :state, true)
     expect(Bosh::OpenStackCloud::NetworkConfigurator).to have_received(:cleanup_ports).with(any_args, ['port_id'])
-    expect(@registry).to have_received(:delete_settings).with('i-foobar')
+    expect(@registry).to have_received(:delete_settings).with(registry_key)
     expect(loadbalancer_configurator).to have_received(:cleanup_memberships).with(
       {
         'lbaas_pool_0' => 'pool-id-0/membership-id-0',
-        'job' => 'bosh'
+        'job' => 'bosh',
+        :registry_key => 'vm-registry-key'
       }
     )
   end
@@ -105,11 +112,12 @@
         cloud.delete_vm('i-foobar')
       }.to raise_error(/BOOM!/)
 
-      expect(@registry).to have_received(:delete_settings).with('i-foobar')
+      expect(@registry).to have_received(:delete_settings).with(registry_key)
       expect(loadbalancer_configurator).to have_received(:cleanup_memberships).with(
         {
           'lbaas_pool_0' => 'pool-id-0/membership-id-0',
-          'job' => 'bosh'
+          'job' => 'bosh',
+          :registry_key => 'vm-registry-key'
         }
       )
     end
@@ -125,7 +133,7 @@
 
 
       expect(Bosh::OpenStackCloud::NetworkConfigurator).to have_received(:cleanup_ports).with(any_args, ['port_id'])
-      expect(@registry).to have_received(:delete_settings).with('i-foobar')
+      expect(@registry).to have_received(:delete_settings).with(registry_key)
     end
   end
 
@@ -143,10 +151,11 @@
       expect(loadbalancer_configurator).to have_received(:cleanup_memberships).with(
         {
           'lbaas_pool_0' => 'pool-id-0/membership-id-0',
-          'job' => 'bosh'
+          'job' => 'bosh',
+          :registry_key => 'vm-registry-key'
         }
       )
-      expect(@registry).to have_received(:delete_settings).with('i-foobar')
+      expect(@registry).to have_received(:delete_settings).with(registry_key)
     end
   end