I want to create a luci app for the https_dns_proxy
package (I've also made the init script more OpenWrt-like and will be submitting PR pending Aaron's review) and I want to conceal some settings from the user and essentially give them the drop-down for picking provider rather than needing to input specific details: https://github.com/stangri/openwrt_packages/blob/master/luci-app-https_dns_proxy/luasrc/model/cbi/https_dns_proxy.lua#L12-L27
The only issue is setting the prov.default
-- how can I obtain the value of url_prefix
from the same section?