Adds new REST API v2/

Addresses #5269

scripts/lua/rest/v2/charts/time/data.lua

@@ -0,0 +1,65 @@
+--
+-- (C) 2013-21 - ntop.org
+--
+
+local dirs = ntop.getDirs()
+
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+
+require "lua_utils"
+local rest_utils = require("rest_utils")
+
+local begin_epoch   = tonumber(_GET["begin_epoch"])
+local end_epoch     = tonumber(_GET["end_epoch"])
+local num_records   = tonumber(_GET["totalRows"]) or 24
+
+local rc = rest_utils.consts.success.ok
+
+local curr = begin_epoch
+
+-- 1 hour is 60*60=3600
+local datasets = {}
+local labels = {}
+
+for i = 1, num_records, 1 do
+
+    if (curr < end_epoch) then
+
+        local key = os.date("%x", curr)
+        if datasets[key] == nil then
+            datasets[key] = 0
+        end
+
+        -- add an hour?
+        datasets[key] = datasets[key] + 1
+
+        curr = curr + 3600 -- ad an hour
+    else
+        break
+    end
+
+end
+
+local flatten = {}
+local i = 1
+
+for k, d in pairsByKeys(datasets) do 
+
+    flatten[i] = d
+    labels[i] = k
+
+    i = i + 1
+end
+
+rest_utils.answer(rc, {
+    data = {
+        labels = labels,
+        datasets = {
+            {data = flatten, label = "Hours in a day", backgroundColor = "#f83a5dfa"}
+        }
+    },
+    options = {
+        maintainAspectRatio = false
+    },
+    redirect_url = ntop.getHttpPrefix() 
+})