Removed plugin from ntopng and migrated all of them

scripts/lua/modules/check_definitions/interface/slow_periodic_activity.lua

@@ -0,0 +1,57 @@
+--
+-- (C) 2019-21 - ntop.org
+--
+
+local alert_consts = require("alert_consts")
+local alerts_api = require("alerts_api")
+local checks = require("checks")
+
+local script
+
+-- #################################################################
+
+local function check_slow_periodic_activity(params)
+   local scripts_stats = interface.getPeriodicActivitiesStats()
+
+   for ps_name, ps_stats in pairs(scripts_stats) do
+      local delta = alerts_api.interface_delta_val(script.key..ps_name --[[ metric name --]], params.granularity, ps_stats["num_is_slow"] or 0)
+
+      local alert = alert_consts.alert_types.alert_slow_periodic_activity.new(
+         ps_name,
+         (ps_stats["max_duration_secs"] or 0) * 1000
+      )
+
+      alert:set_score_warning()
+      alert:set_granularity(params.granularity)
+      alert:set_subtype(ps_name)
+
+      if delta > 0 then
+	 -- tprint({ps_name = ps_name, s = ">>>>>>>>>>>>>>>>>>>>>> TRIGGER"})
+         alert:trigger(params.alert_entity, nil, params.cur_alerts)
+      else
+	 -- tprint({ps_name = ps_name, s = "---------------------- RELEASE"})
+         alert:release(params.alert_entity, nil, params.cur_alerts)
+      end
+   end
+end
+
+-- #################################################################
+
+script = {
+   -- Script category
+   category = checks.check_categories.internals,
+
+
+   hooks = {
+      min = check_slow_periodic_activity,
+   },
+
+   gui = {
+      i18n_title = "alerts_dashboard.slow_periodic_activity",
+      i18n_description = "alerts_dashboard.slow_periodic_activity_descr",
+   }
+}
+
+-- #################################################################
+
+return script