prometheus-node-exporter-lua: hostad ubus stats

There is already the hostapd_stations exporter, which uses
hostapd-utils (more precisely hostapd-cli) to get client statistics.
However, the ubus interface is permanently integrated under hostapd
in OpenWrt. So this exporter needs one dependency less.

For now it exports mainly the rrm statistics. Many people are
interested in what your device supports. The exporter provides
information about the radio-resource-managment extensions.

Signed-off-by: Nick Hainke <vincent@systemli.org>

utils/prometheus-node-exporter-lua/Makefile

@@ -4,7 +4,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=prometheus-node-exporter-lua
-PKG_VERSION:=2020.10.01
+PKG_VERSION:=2020.10.10
 PKG_RELEASE:=1
 
 PKG_MAINTAINER:=Etienne CHAMPETIER <champetier.etienne@gmail.com>
@@ -100,6 +100,17 @@ define Package/prometheus-node-exporter-lua-hostapd_stations/install
 	$(INSTALL_BIN) ./files/usr/lib/lua/prometheus-collectors/hostapd_stations.lua $(1)/usr/lib/lua/prometheus-collectors/
 endef
 
+define Package/prometheus-node-exporter-lua-hostapd_ubus_stations
+  $(call Package/prometheus-node-exporter-lua/Default)
+  TITLE+= (hostapd_ubus_stations collector)
+  DEPENDS:=prometheus-node-exporter-lua +luabitop +libubus-lua
+endef
+
+define Package/prometheus-node-exporter-lua-hostapd_ubus_stations/install
+	$(INSTALL_DIR) $(1)/usr/lib/lua/prometheus-collectors
+	$(INSTALL_BIN) ./files/usr/lib/lua/prometheus-collectors/hostapd_ubus_stations.lua $(1)/usr/lib/lua/prometheus-collectors/
+endef
+
 define Package/prometheus-node-exporter-lua-ltq-dsl
   $(call Package/prometheus-node-exporter-lua/Default)
   TITLE+= (lantiq dsl collector)
@@ -193,6 +204,7 @@ $(eval $(call BuildPackage,prometheus-node-exporter-lua-bmx6))
 $(eval $(call BuildPackage,prometheus-node-exporter-lua-bmx7))
 $(eval $(call BuildPackage,prometheus-node-exporter-lua-dawn))
 $(eval $(call BuildPackage,prometheus-node-exporter-lua-hostapd_stations))
+$(eval $(call BuildPackage,prometheus-node-exporter-lua-hostapd_ubus_stations))
 $(eval $(call BuildPackage,prometheus-node-exporter-lua-ltq-dsl))
 $(eval $(call BuildPackage,prometheus-node-exporter-lua-nat_traffic))
 $(eval $(call BuildPackage,prometheus-node-exporter-lua-netstat))

utils/prometheus-node-exporter-lua/files/usr/lib/lua/prometheus-collectors/hostapd_ubus_stations.lua

@@ -0,0 +1,68 @@
+local ubus = require "ubus"
+local bit = require "bit32"
+
+local function get_wifi_interfaces() -- based on hostapd_stations.lua
+  local u = ubus.connect()
+  local status = u:call("network.wireless", "status", {})
+  local interfaces = {}
+
+  for _, dev_table in pairs(status) do
+    for _, intf in ipairs(dev_table['interfaces']) do
+      table.insert(interfaces, intf['ifname'])
+    end
+  end
+
+  return interfaces
+end
+
+local function scrape()
+  local metric_hostapd_ubus_station_rrm_caps_link_measurement =
+    metric("hostapd_ubus_station_rrm_caps_link_measurement", "gauge")
+  local metric_hostapd_ubus_station_rrm_caps_neighbor_report =
+    metric("hostapd_ubus_station_rrm_caps_neighbor_report", "gauge")
+  local metric_hostapd_ubus_station_rrm_caps_beacon_report_passive =
+    metric("hostapd_ubus_station_rrm_caps_beacon_report_passive", "gauge")
+  local metric_hostapd_ubus_station_rrm_caps_beacon_report_active =
+    metric("hostapd_ubus_station_rrm_caps_beacon_report_active", "gauge")
+  local metric_hostapd_ubus_station_rrm_caps_beacon_report_table =
+    metric("hostapd_ubus_station_rrm_caps_beacon_report_table", "gauge")
+  local metric_hostapd_ubus_station_rrm_caps_lci_measurement =
+    metric("hostapd_ubus_station_rrm_caps_lci_measurement", "gauge")
+  local metric_hostapd_ubus_station_rrm_caps_ftm_range_report =
+    metric("hostapd_ubus_station_rrm_caps_ftm_range_report", "gauge")
+
+  local function evaluate_metrics(ifname, freq, station, vals)
+    local label_station = {
+      ifname = ifname,
+      freq = freq,
+      station = station
+    }
+    local rrm_caps_link_measurement = bit.band(bit.lshift(1, 0), vals['rrm'][1]) > 0 and 1 or 0
+    local rrm_caps_neighbor_report = bit.band(bit.lshift(1, 1), vals['rrm'][1]) > 0 and 1 or 0
+    local rrm_caps_beacon_report_passive = bit.band(bit.lshift(1, 4), vals['rrm'][1]) > 0 and 1 or 0
+    local rrm_caps_beacon_report_active = bit.band(bit.lshift(1, 5), vals['rrm'][1]) > 0 and 1 or 0
+    local rrm_caps_beacon_report_table = bit.band(bit.lshift(1, 6), vals['rrm'][1]) > 0 and 1 or 0
+    local rrm_caps_lci_measurement = bit.band(bit.lshift(1, 4), vals['rrm'][2]) > 0 and 1 or 0
+    local rrm_caps_ftm_range_report = bit.band(bit.lshift(1, 2), vals['rrm'][5]) > 0 and 1 or 0
+
+    metric_hostapd_ubus_station_rrm_caps_link_measurement(label_station, rrm_caps_link_measurement)
+    metric_hostapd_ubus_station_rrm_caps_neighbor_report(label_station, rrm_caps_neighbor_report)
+    metric_hostapd_ubus_station_rrm_caps_beacon_report_passive(label_station, rrm_caps_beacon_report_passive)
+    metric_hostapd_ubus_station_rrm_caps_beacon_report_active(label_station, rrm_caps_beacon_report_active)
+    metric_hostapd_ubus_station_rrm_caps_beacon_report_table(label_station, rrm_caps_beacon_report_table)
+
+    metric_hostapd_ubus_station_rrm_caps_lci_measurement(label_station, rrm_caps_lci_measurement)
+    metric_hostapd_ubus_station_rrm_caps_ftm_range_report(label_station, rrm_caps_ftm_range_report)
+  end
+
+  for _, ifname in ipairs(get_wifi_interfaces()) do
+    local u = ubus.connect()
+    local clients_call = u:call("hostapd." .. ifname, "get_clients", {})
+
+    for client, client_table in pairs(clients_call['clients']) do
+      evaluate_metrics(ifname,  clients_call['freq'], client, client_table)
+    end
+  end
+end
+
+return { scrape = scrape }