Avoid possible NPE in VirtualMachine.Device method

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ### unreleased
 
+* Avoid possible NPE in VirtualMachine.Device method
+
 * Add support for OpaqueNetwork type to Finder
 
 * Add HostConfigManager.AccountManager support for ESX 5.5

govc/CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ### unreleased
 
+* Add object.reload command
+
 * Add ESX 5.5 support to host.account commands
 
 ### 0.11.1 (2016-10-27)

govc/object/reload.go

@@ -0,0 +1,88 @@
+/*
+Copyright (c) 2016 VMware, Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package object
+
+import (
+	"context"
+	"flag"
+
+	"github.com/vmware/govmomi/govc/cli"
+	"github.com/vmware/govmomi/govc/flags"
+	"github.com/vmware/govmomi/vim25/methods"
+	"github.com/vmware/govmomi/vim25/types"
+)
+
+type reload struct {
+	*flags.DatacenterFlag
+}
+
+func init() {
+	cli.Register("object.reload", &reload{})
+}
+
+func (cmd *reload) Register(ctx context.Context, f *flag.FlagSet) {
+	cmd.DatacenterFlag, ctx = flags.NewDatacenterFlag(ctx)
+	cmd.DatacenterFlag.Register(ctx, f)
+}
+
+func (cmd *reload) Usage() string {
+	return "PATH..."
+}
+
+func (cmd *reload) Description() string {
+	return `Reload managed object state.
+
+Examples:
+  govc datastore.upload $vm.vmx $vm/$vm.vmx
+  govc object.reload /dc1/vm/$vm`
+}
+
+func (cmd *reload) Process(ctx context.Context) error {
+	if err := cmd.DatacenterFlag.Process(ctx); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (cmd *reload) Run(ctx context.Context, f *flag.FlagSet) error {
+	if f.NArg() == 0 {
+		return flag.ErrHelp
+	}
+
+	c, err := cmd.Client()
+	if err != nil {
+		return err
+	}
+
+	objs, err := cmd.ManagedObjects(ctx, f.Args())
+	if err != nil {
+		return err
+	}
+
+	for _, obj := range objs {
+		req := types.Reload{
+			This: obj,
+		}
+
+		_, err = methods.Reload(ctx, c, &req)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

govc/test/device.bats

@@ -260,3 +260,23 @@ load test_helper
   run govc vm.disk.create -vm "$vm" -name disk-16 -size 1K
   assert_success
 }
+
+
+@test "device nil config" {
+  vm=$(new_empty_vm)
+
+  run govc device.ls -vm "$vm"
+  assert_success
+
+  run govc datastore.rm "$vm"
+  assert_success
+
+  run govc object.reload "vm/$vm"
+  assert_success
+
+  run govc device.ls -vm "$vm"
+  assert_failure
+
+  run govc vm.unregister "$vm"
+  assert_success
+}

object/virtual_machine.go

@@ -302,11 +302,21 @@ func (v VirtualMachine) WaitForNetIP(ctx context.Context, v4 bool) (map[string][
 func (v VirtualMachine) Device(ctx context.Context) (VirtualDeviceList, error) {
 	var o mo.VirtualMachine
 
-	err := v.Properties(ctx, v.Reference(), []string{"config.hardware.device"}, &o)
+	err := v.Properties(ctx, v.Reference(), []string{"config.hardware.device", "summary.runtime.connectionState"}, &o)
 	if err != nil {
 		return nil, err
 	}
 
+	// Quoting the SDK doc:
+	//   The virtual machine configuration is not guaranteed to be available.
+	//   For example, the configuration information would be unavailable if the server
+	//   is unable to access the virtual machine files on disk, and is often also unavailable
+	//   during the initial phases of virtual machine creation.
+	if o.Config == nil {
+		return nil, fmt.Errorf("%s Config is not available, connectionState=%s",
+			v.Reference(), o.Summary.Runtime.ConnectionState)
+	}
+
 	return VirtualDeviceList(o.Config.Hardware.Device), nil
 }