Accommodate non-NSX-T Distributed Virtual Switches

Previously the vSphere CPI NSX-T Policy API assumed _all_ Distributed
Virtual Switches (DVSes) were NSX-T Segments, but that assummption was
false; DVSes may be managed by vSphere and not NSX-T.

We now check whether the network interface controller (NIC) is
NSX-T-managed before attempting to tag the NIC's port with NSX-T
metadata.

fixes:
```
unable to create bosh vm:CPI 'set_vm_metadata' method responded with error: CmdError{"type":"Unknown","message":"Invalid Query","ok_to_retry":false}
```

[fixes #302]
[#179334136](https://www.pivotaltracker.com/story/show/179334136)

Signed-off-by: Brian Cunnie <bcunnie@vmware.com>

src/vsphere_cpi/lib/cloud/vsphere/resources/vm.rb

@@ -79,20 +79,20 @@ def system_disk
       end
 
       def get_nsxt_segment_vif_list
-        nsxt_nics = get_nsxt_nics
-        if nsxt_nics.empty?
+        potential_nsxt_nics = get_potential_nsxt_nics
+        if potential_nsxt_nics.empty?
           logger.info("No NSXT network/nic present on the VM")
           return nil
         end
         nsxt_networks_id_name_map = get_nsxt_networks_id_name_map
-        nsxt_nics.reduce([]) do |list, nic|
+        potential_nsxt_nics.reduce([]) do |list, nic|
           if nic.backing.is_a?(VimSdk::Vim::Vm::Device::VirtualEthernetCard::DistributedVirtualPortBackingInfo)
             segment_name = nsxt_networks_id_name_map[nic.backing.port.portgroup_key]
           else
             segment_name = nsxt_networks_id_name_map[nic.backing.opaque_network_id]
           end
           port_id = nic.external_id
-          list << [segment_name, port_id]
+          list << [segment_name, port_id] unless segment_name.nil?
         end
       end
 
@@ -419,7 +419,7 @@ def self.create_edit_device_spec(device)
 
       private
 
-      def get_nsxt_nics
+      def get_potential_nsxt_nics
         nsxt_nics = nics.select do |nic|
           nic.backing.is_a?(VimSdk::Vim::Vm::Device::VirtualEthernetCard::DistributedVirtualPortBackingInfo) ||
             ( nic.backing.is_a?(VimSdk::Vim::Vm::Device::VirtualEthernetCard::OpaqueNetworkBackingInfo) &&

src/vsphere_cpi/spec/integration/nsxt_spec.rb

@@ -538,6 +538,41 @@ def initialize(name: "BOSH-CPI-test-#{SecureRandom.uuid}", id: SecureRandom.uuid
           expect(server_pool_2.members).to be_nil
         end
       end
+
+      context 'with non-nsxt distributed virtual switches' do
+        let(:nsxt_spec) { {} }
+        let(:dvpg_name) { ENV.fetch('BOSH_VSPHERE_CPI_FOLDER_PORTGROUP_ONE') }
+        let(:policy_network_spec) do
+          {
+            'static-bridged' => {
+              'ip' => "169.254.#{rand(1..254)}.#{rand(4..254)}",
+              'netmask' => '255.255.254.0',
+              'cloud_properties' => { 'name' => segment_1.name },
+              'default' => ['dns', 'gateway'],
+              'dns' => ['169.254.1.2'],
+              'gateway' => '169.254.1.3'
+            },
+            'static' => {
+              'ip' => "169.254.#{rand(1..254)}.#{rand(4..254)}",
+              'netmask' => '255.255.254.0',
+              'cloud_properties' => { 'name' => dvpg_name },
+              'default' => ['dns', 'gateway'],
+              'dns' => ['169.254.1.2'],
+              'gateway' => '169.254.1.3'
+            }
+          }
+        end
+        it 'creates a VM without errors' do
+          simple_vm_lifecycle(cpi, '', vm_type, policy_network_spec) do |vm_id|
+            cpi.set_vm_metadata(vm_id, {'id' => 'foo'})
+
+            vm = @cpi.vm_provider.find(vm_id)
+            segment_names = vm.get_nsxt_segment_vif_list.map { |x| x[0] }
+            expect(segment_names.length).to eq(1)
+            expect(segment_names).to include(segment_1.name)
+          end
+        end
+      end
     end
   end
 

src/vsphere_cpi/spec/unit/cloud/vsphere/resources/vm_spec.rb

@@ -651,4 +651,32 @@
       end
     end
   end
+
+  describe '#get_nsxt_segment_vif_list' do
+    let (:nic0) { instance_double(VimSdk::Vim::Vm::Device::VirtualEthernetCard) }
+    before(:each) do
+      expect(subject).to receive(:get_potential_nsxt_nics).and_return([nic0])
+      allow(nic0).to receive_message_chain(:backing, :is_a?).and_return(true)
+      expect(nic0).to receive(:external_id).and_return('nic-external-id')
+      allow(nic0).to receive_message_chain(:backing, :port, :portgroup_key).and_return('nic-portgroup-key')
+    end
+
+    context "when the NIC is an NSX-T DVS NIC" do
+      before do
+        allow(subject).to receive(:get_nsxt_networks_id_name_map).and_return({'nic-portgroup-key' => 'some-segment-name'})
+      end
+      it "is not returned in the list of NSX-T vifs" do
+        expect(subject.get_nsxt_segment_vif_list).to match_array([["some-segment-name", "nic-external-id"]])
+      end
+    end
+
+    context "when the NIC is a DVS NIC but NOT an NSX-T DVS nic" do
+      before do
+        allow(subject).to receive(:get_nsxt_networks_id_name_map).and_return({})
+      end
+      it "is not returned in the list of NSX-T vifs" do
+        expect(subject.get_nsxt_segment_vif_list).to be_nil
+      end
+    end
+  end
 end