Migrates alerts to an object-oriented implementation

scripts/lua/modules/alert_definitions/alert_influxdb_error.lua

@@ -2,39 +2,51 @@
 -- (C) 2019-20 - ntop.org
 --
 
+-- ##############################################
+
 local alert_keys = require "alert_keys"
+-- Import the classes library.
+local classes = require "classes"
+-- Make sure to import the Superclass!
+local alert = require "alert"
 
--- #######################################################
+-- ##############################################
 
--- @brief Prepare an alert table used to generate the alert
--- @param alert_severity A severity as defined in `alert_severities`
--- @param alert_granularity A granularity as defined in `alert_consts.alerts_granularities`
--- @param last_error A string with the lastest influxdb error
--- @return A table with the alert built
-local function createInfluxdbError(alert_severity, alert_granularity, last_error)
-   local threshold_type = {
-      alert_severity = alert_severity,
-      alert_granularity = alert_granularity,
-      alert_type_params = {
-	 error_msg = last_error
-      },
-   }
+local alert_influxdb_error = classes.class(alert)
 
-   return threshold_type
-end
+-- ##############################################
 
--- #######################################################
-
-local function formatInfluxdbErrorMessage(ifid, alert, status)
-  return(status.error_msg)
-end
-
--- #######################################################
-
-return {
+alert_influxdb_error.meta = {
   alert_key = alert_keys.ntopng.alert_influxdb_error,
   i18n_title = "alerts_dashboard.influxdb_error",
-  i18n_description = formatInfluxdbErrorMessage,
   icon = "fas fa-database",
-  creator = createInfluxdbError,
 }
+
+-- ##############################################
+
+-- @brief Prepare an alert table used to generate the alert
+-- @param last_error A string with the lastest influxdb error
+-- @return A table with the alert built
+function alert_influxdb_error:init(last_error)
+   -- Call the paren constructor
+   self.super:init()
+
+   self.alert_type_params = {
+    error_msg = last_error
+   }
+end
+
+-- #######################################################
+
+-- @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_influxdb_error.format(ifid, alert, alert_type_params)
+  return(alert_type_params.error_msg)
+end
+
+-- #######################################################
+
+return alert_influxdb_error