vsphere-iso: Add support for vApp properties

[ghost]

This issue was originally opened by @jpbuecken as hashicorp/packer#10319. It was migrated here as a result of the Packer plugin split. The original body of the issue is below.

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Description

In vSphere, you can enable vApp Options of a VM via Configure -> vApp Options -> Edit
After that, you can add Properties to the vApp / VM (same window)

This should be possible via the vsphere-iso builder.

Use Case(s)

With this, you can create a VM with vApp Properties.
Use Case 1: You can add a public-keys property. Configure your Suse autoyast / Redhat/Ubuntu kickstart / Ubuntu preseed to make use of the value during boot (write your own script or make use of cloud-init).
After you have done this, your new vm can be used in turn as a source for vsphere-clone builder.
Since vsphere-clone supports temporary keys for the public-keys property, there is no need to store a password or public-key file in your source image.
I see this as an absolut security win.

Use Case 2: Similar to vsphere-clone, vsphere-iso may use the public-keys property itself:

1. vsphere-iso creates the vapp property public-keys
2. vsphere-iso is able to generate temporary key pairs and add them as value to the public-keys (additional new feature, same logic as vsphere-clone)
3. Your automatic installation process make use of the value in public-keys and add them to your connect user (e.g. root)
4. vsphere-iso can connect with the ssh communicator with the temporary key pair
   Now the same argument as above applies, there is no need to store a hardcoded password or key files inside your vm before you connect with vsphere-iso. E.g. we have the policy to recreate key files regularly. If they are created and removed "on the fly" temporary, this policy is easily fulfilled.

Potential configuration

     "builders": [
      {
         "type":                      "vsphere-iso",
[...]
        
        "vapp": {
             "enable_vapp_options": true
            "properties": {
                "public-keys": "",
            }
        }
     ]

Potential References

https://www.packer.io/docs/builders/vmware/vsphere-clone#ssh (search for public-keys and vapp on the side)

[khelansible]

Any ETA on this feature will help my planning.

Many Thanks

[theunknownport]

In the need of this feature. Setting vApps like this:

configuration_parameters = {
    "disk.EnableUUID" = "true",
        "vAppConfig" = <<EOF
ALOT OF XML CODE HERE

doesn't work for me.

[MrKeiKun]

Any update regarding this feature?

[Gankarloo]

Also very interested in an update for this feature

[aatzer]

Any updates regarding this feature?

[consummo]

I'm also very interested in this feature.