Return IP from multiple NICs

[Colin]

You can use the ip command in an exec node to fetch the data you want. For example to get information on all interfaces (try these in a terminal first so you can see what you are dealing with)
ip address show
so you could run that and then parse the result to find what you want. Alternatively, to get the data for particular interfaces you can run
ip address show eth0
ip address show wlan0
You could do some of the parsing in the command, so to get the ip4 address (I guess you want that rather than ip6) for wlan0
ip address show wlan0 | grep "inet "
which should then be quite easy to extract the address from.
If you study the docs for the ip command there may well be options you can specify to home in on exactly what you want, there are lots of options and I don't know it well enough to say.