# encoding: utf-8 require "yaml" # persistence module LogStash module PluginMixins module Jdbc class ValueTracking def self.build_last_value_tracker(plugin) if plugin.use_column_value && plugin.tracking_column_type == "numeric" # use this irrespective of the jdbc_default_timezone setting klass = NumericValueTracker else if plugin.jdbc_default_timezone.nil? || plugin.jdbc_default_timezone.empty? # no TZ stuff for Sequel, use Time klass = TimeValueTracker else # Sequel does timezone handling on DateTime only klass = DateTimeValueTracker end end handler = NullFileHandler.new(plugin.last_run_metadata_path) if plugin.record_last_run handler = FileHandler.new(plugin.last_run_metadata_path) end if plugin.clean_run handler.clean end instance = klass.new(handler) end attr_reader :value def initialize(handler) @file_handler = handler set_value(get_initial) end def get_initial # override in subclass end def set_value(value) # override in subclass end def write @file_handler.write(@value) end end class NumericValueTracker < ValueTracking def get_initial @file_handler.read || 0 end def set_value(value) return unless value.is_a?(Numeric) @value = value end end class DateTimeValueTracker < ValueTracking def get_initial @file_handler.read || DateTime.new(1970) end def set_value(value) if value.respond_to?(:to_datetime) @value = value.to_datetime else @value = DateTime.parse(value) end end end class TimeValueTracker < ValueTracking def get_initial @file_handler.read || Time.at(0).utc end def set_value(value) if value.respond_to?(:to_time) @value = value.to_time else @value = DateTime.parse(value).to_time end end end class FileHandler def initialize(path) @path = path @exists = ::File.exist?(@path) end def clean return unless @exists ::File.delete(@path) @exists = false end def read return unless @exists YAML.load(::File.read(@path)) end def write(value) ::File.write(@path, YAML.dump(value)) @exists = true end end class NullFileHandler def initialize(path) end def clean end def read end def write(value) end end end end end