Migrates alerts to an object-oriented implementation

scripts/lua/modules/alert_definitions/alert_device_disconnection.lua

@@ -2,12 +2,49 @@
 -- (C) 2019-20 - ntop.org
 --
 
+-- ##############################################
+
 local alert_keys = require "alert_keys"
 local alert_creators = require "alert_creators"
+-- Import the classes library.
+local classes = require "classes"
+-- Make sure to import the Superclass!
+local alert = require "alert"
+
+-- ##############################################
+
+local alert_device_disconnection = classes.class(alert)
+
+-- ##############################################
+
+alert_device_disconnection.meta = {
+  alert_key = alert_keys.ntopng.alert_device_disconnection,
+  i18n_title = "alerts_dashboard.device_disconnection",
+  icon = "fas fa-sign-out",
+}
+
+-- ##############################################
+
+-- @brief Prepare an alert table used to generate the alert
+-- @param device The a string with the name or ip address of the device that connected/disconnected
+-- @return A table with the alert built
+function alert_device_disconnection:init(device)
+   -- Call the paren constructor
+   self.super:init()
+
+   self.alert_type_params = {
+    device = device,
+   }
+end
 
 -- #######################################################
 
-local function formatDeviceDisconnectionAlert(ifid, alert, info)
+-- @brief Format an alert into a human-readable string
+-- @param ifid The integer interface id of the generated alert
+-- @param alert The alert description table, including alert data such as the generating entity, timestamp, granularity, type
+-- @param alert_type_params Table `alert_type_params` as built in the `:init` method
+-- @return A human-readable string
+function alert_device_disconnection.format(ifid, alert, alert_type_params)
   local device = info.device
 
   if not device or device == "" then
@@ -22,10 +59,4 @@ end
 
 -- #######################################################
 
-return {
-  alert_key = alert_keys.ntopng.alert_device_disconnection,
-  i18n_title = "alerts_dashboard.device_disconnection",
-  i18n_description = formatDeviceDisconnectionAlert,
-  icon = "fas fa-sign-out",
-  creator = alert_creators.createDeviceConnectionDisconnection,
-}
+return alert_device_disconnection