Adds new REST API v2/

Addresses #5269

scripts/lua/rest/v2/get/alert/severity/consts.lua

@@ -0,0 +1,31 @@
+--
+-- (C) 2013-21 - ntop.org
+--
+
+local dirs = ntop.getDirs()
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+
+require "lua_utils"
+local json = require "dkjson"
+local alert_severities = require "alert_severities"
+local rest_utils = require "rest_utils"
+
+--
+-- Read all the defined alert severity constants
+-- Example: curl -u admin:admin -H "Content-Type: application/json" http://localhost:3000/lua/rest/v2/get/alert/severity/consts.lua
+--
+-- NOTE: in case of invalid login, no error is returned but redirected to login
+--
+
+local rc = rest_utils.consts.success.ok
+local res = {}
+
+for severity, severity_descr in pairs(alert_severities) do
+   res[#res + 1] = {
+     severity = severity,
+     id = severity_descr.severity_id,
+   }
+end
+
+rest_utils.answer(rc, res)
+