Add snapshot size to snapshot.tree

[Matty9191]

It would be really cool to be able to retrieve the size of each VM snapshot by passing a size argument to snapshot.tree.

[dougm]

Taking a quick look where we can find this data, it would be useful if you could share the output of this command in your environment and let us know if the Size field alone looks correct:

% govc vm.info -json '*' | jq '.VirtualMachines[].LayoutEx.File[] | select(.Type == "snapshotData")'
{
  "Key": 6,
  "Name": "[datastore1] foo/foo-Snapshot1.vmsn",
  "Type": "snapshotData",
  "Size": 1120676,
  "UniqueSize": 1120676,
  "BackingObjectId": "",
  "Accessible": true
}

[atc0005]

@dougm Having this support would likely be useful for other clients of the govmomi package as well. Do you see adding it as a field to the types.VirtualMachineSnapshotTree type?

[dougm]

@atc0005 agreed it would be generally useful. We can't add fields to vim25/types however, those are generated from SDK spec (wsdl). But you can add helper types and methods by using a different type. A few examples:

govmomi/object/authorization_manager.go

Lines 40 to 60 in c43a1c8

	type AuthorizationRoleList []types.AuthorizationRole
	func (l AuthorizationRoleList) ById(id int32) *types.AuthorizationRole {
	for _, role := range l {
	if role.RoleId == id {
	return &role
	}
	}
	return nil
	}
	func (l AuthorizationRoleList) ByName(name string) *types.AuthorizationRole {
	for _, role := range l {
	if role.Name == name {
	return &role
	}
	}
	return nil
	}

govmomi/license/manager.go

Lines 183 to 195 in c43a1c8

	type InfoList []types.LicenseManagerLicenseInfo
	func (l InfoList) WithFeature(key string) InfoList {
	var result InfoList
	for _, license := range l {
	if HasFeature(license, key) {
	result = append(result, license)
	}
	}
	return result
	}

govmomi/object/virtual_device_list.go

Lines 41 to 42 in c43a1c8

	// VirtualDeviceList provides helper methods for working with a list of virtual devices.
	type VirtualDeviceList []types.BaseVirtualDevice

govmomi/object/host_firewall_system.go

Lines 81 to 85 in c43a1c8

	// HostFirewallRulesetList provides helpers for a slice of types.HostFirewallRuleset
	type HostFirewallRulesetList []types.HostFirewallRuleset
	// ByRule returns a HostFirewallRulesetList where Direction, PortType and Protocol are equal and Port is within range
	func (l HostFirewallRulesetList) ByRule(rule types.HostFirewallRule) HostFirewallRulesetList {

There's more too, but those should give you the idea. I think similar could be done for types.VirtualMachineSnapshotTree

[atc0005]

@dougm: Taking a quick look where we can find this data, it would be useful if you could share the output of this command in your environment and let us know if the Size field alone looks correct:

FWIW: This isn't from govc, but accessing the Size field seems to yield the size of the vmsn file itself (e.g., RHEL7-TEST-Snapshot9.vmsn) and not the snapshot as "seen" by Get-Snapshot PowerCLI cmdlet or the vSphere web client. Your question was from a bit ago, but since I'm working on this I thought I'd offer the feedback, just in case it was useful.

[dougm]

#2269 added a -s flag to the snapshot.tree command.