Chef GCP firewall how to set multiple ports?

Question

Chef

gcompute_firewall 'test-fw-allow-ssh' do
  action :create
  allowed [
    {
      ip_protocol: 'tcp',
      ports: ['8081']  
    }
  ]
  target_tags [
    'instance-test'
  ]
  project ENV['GCP_PROJECT'] # ex: 'my-test-project'
  credential 'mycred'
end

1) How to set multiple ports?
So:

allowed                 [
    {
      ip_protocol string,
      ports       [
        string,
        ...
      ],
    },
    ...
  ]

2) Where can I find the dock for the gcompute_firewall resource?
Here: https://supermarket.chef.io/cookbooks/google-gcompute
3) I want to use chef as IaC is it worth it or is it customary to use other tools like teraform for this?