Minetest - Metadata spy

gistfile1.lua

minetest.register_craftitem("metaspy:metaspy", {
	description = "Metadata Spy",
	inventory_image = "default_wood",
	on_use = function(itemstack, user, pointed_thing)
		local plname = user:get_player_name()
		local send = minetest.chat_send_player
		if pointed_thing.type == "node" then
			local meta = minetest.get_meta(pointed_thing.under):to_table()
			if meta.fields then
				send(plname, "METAFIELDS:")
				for k, v in pairs(meta.fields) do
					send(plname, ("  %q = %q"):format(k, tostring(v)))
				end
			end
			if meta.inventory then
				send(plname, "INVENTORY LISTS:")
				for k, v in pairs(meta.inventory) do
					send(plname, ("  %q (%d items)"):format(k, #v))
				end
			end
		end
	end,
})