How to use packer export_opts? - virtualbox

Question

I build a VirtualBox VM using Packer and I would like to set some VM meta data (e.g. description, version) using the export_opts parameter. The docs say
export_opts (array of strings) - Additional options to pass to the VBoxManage export. This can be useful for passing product information to include in the resulting appliance file.
I am trying to do this in a bash script calling packer:
desc=' ... some ...'
desc+=' ... multiline ...'
desc+=' ... description ...'
# this is actually done using printf, shortened for clarity
export_opts='[ "version", "0.2.0", "description", "${desc}" ]'
# the assembled string looks OK
echo "export_opts: ${export_opts}"
packer build \
... (more options) ...
-var "export_opts=${export_opts}" \
... (more options) ...
<packer configuration file>
I also tried --version instead of version and putting version and the value into the same string, but none of this works; once exported and re-imported, the VM description is empty.
Does anyone have some working sample code or can help me out with what I'm doing wrong ?
Thank you very much.
Update:
Following Anthony Staunton's approach, I figured out that adding
"export_opts": [ "--vsys", "0", "--version", "0.2.0", "--description", "some test description" ],
to the Packer JSON file does work; passing the same string as --var to Packer does not work.

Answer 1

Fixed the problem at long last, updated the packer documentation with the example below, pull requests pending:
Packer JSON configuration file example:
{
"type": "virtualbox-ovf",
"export_opts":
[
"--manifest",
"--vsys", "0",
"--description", "{{user `vm_description`}}",
"--version", "{{user `vm_version`}}"
],
"format": "ova",
}
A VirtualBox VM description may contain arbitrary strings; the GUI interprets HTML formatting. However, the JSON format does not allow arbitrary newlines within a value. Add a multi-line description by preparing the string in the shell before the packer call like this (shell > continuation character snipped for easier copy & paste):
vm_description='some
multiline
description'
vm_version='0.2.0'
packer build \
-var "vm_description=${vm_description}" \
-var "vm_version=${vm_version}" \
"packer_conf.json"

Answer 2

You may have to specify the data as
in your packer json file
"export_opts": [ "--vsys 0 --version \"0.2.0\"", "{{.Name}} --description \"${desc}\" " ],