dokytree/samples/it_v1/schemas_builder/parts/netdev_roles.json

{
	"$schema": "http://json-schema.org/draft-07/schema#",
  "properties": {
		"roles": {
			"type": "array",
			"items": {
				"anyOf": [
					{ "type": "string" },
					{ "enum": [
						"''",
						"'DHCP'",
						"'DNS'",
						"'VPN'",
						"'Firewall'",
						"'Router'"
					]}
				]
			}	
		}
	}
}