Add metrics mod

mods/ctf_metrics/depends.txt

@@ -0,0 +1,3 @@
+ctf
+ctf_stats
+prometheus?

mods/ctf_metrics/init.lua

@@ -0,0 +1,29 @@
+if not minetest.global_exists("prometheus") then
+	return
+end
+
+local kill_counter = 0
+ctf.register_on_killedplayer(function(victim, killer, type)
+	kill_counter = kill_counter + 1
+end)
+
+local function step()
+	prometheus.post("minetest_kills", kill_counter)
+	kill_counter = 0
+
+	local sum = 0
+	local avg = 0
+	if #minetest.get_connected_players() > 0 then
+		for _, player in pairs(minetest.get_connected_players()) do
+			local total, match = ctf_stats.player(player:get_player_name())
+			sum = sum + total.score
+		end
+		avg = sum / #minetest.get_connected_players()
+	end
+
+	prometheus.post("minetest_ctf_score_total", sum)
+	prometheus.post("minetest_ctf_score_avg", avg)
+
+	minetest.after(15, step)
+end
+minetest.after(15, step)