Initial rework of widget datasources and transformations

scripts/lua/modules/datasources/datasource.lua

@@ -0,0 +1,57 @@
+--
+-- (C) 2013-21 - ntop.org
+--
+
+local dirs = ntop.getDirs()
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+package.path = dirs.installdir .. "/scripts/lua/modules/datasources/?.lua;" .. package.path
+
+local json = require "dkjson"
+local rest_utils = require "rest_utils"
+-- Import the classes library.
+local classes = require "classes"
+
+-- ##############################################
+
+local datasource = classes.class()
+
+-- ##############################################
+
+-- @brief Base class constructor
+function datasource:init()
+end
+
+-- ##############################################
+
+-- @brief Deserializes REST endpoint response into an internal datamodel
+-- @param rest_response_data Response data as obtained from the REST call
+function datasource:deserialize(rest_response_data)
+   if rest_response_data and rest_response_data.RESPONSE_CODE == 200 then
+      local data = json.decode(rest_response_data.CONTENT)
+      local when = os.time()
+
+      if data and data.rc == rest_utils.consts.success.ok.rc then
+	 self.m = self.meta.datamodel:create(data.rsp.header)
+
+	 for _, row in ipairs(data.rsp.rows) do
+	    self.m:appendRow(when, data.rsp.header, row)
+	 end
+      end
+   end
+end
+
+-- ##############################################
+
+-- @brief Transform data according to the specified transformation
+-- @param data The data to be transformed
+-- @param transformation The transformation to be applied
+-- @return transformed data
+function datasource:transform(transformation)
+   return self.m:getData(transformation)
+end
+
+-- ##############################################
+
+return datasource
+
+-- ##############################################