https://github.com/vyos/vyos-1x/blob/current/src/op_mode/firewall.py#L66
firewall['interface'] = []
needs to be
firewall['interface'] = {}
otherwise you end up with, when you try to do show firewall name <name>
Traceback (most recent call last): Rule Information File "/usr/libexec/vyos/op_mode/firewall.py", line 343, in <module> show_firewall_rule(args.name, args.rule, args.ipv6) File "/usr/libexec/vyos/op_mode/firewall.py", line 224, in show_firewall_rule firewall = get_config_firewall(conf, name, ipv6) File "/usr/libexec/vyos/op_mode/firewall.py", line 76, in get_config_firewall get_firewall_interfaces(firewall, name, ipv6) File "/usr/libexec/vyos/op_mode/firewall.py", line 31, in get_firewall_interfaces for ifname, if_conf in firewall['interface'].items(): AttributeError: 'list' object has no attribute 'items'