Class: Dynflow::Dispatcher::ClientDispatcher::PingCache

Inherits:
Object
  • Object
show all
Defined in:
lib/dynflow/dispatcher/client_dispatcher.rb

Overview

Class used for reducing the number of sent Pings among worlds. World’s coordinator record include the time when was the world seen for the last time. This class can be used to query this information and determine whether the record is “fresh enough” or whether the Ping really needs to be sent.

Constant Summary collapse

TIME_FORMAT =

Format string used for formating and parsing times

'%Y-%m-%d %H:%M:%S.%L'
DEFAULT_MAX_AGE = 
60

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(world, max_age = DEFAULT_MAX_AGE) ⇒ PingCache

Returns a new instance of PingCache.

Parameters:

  • world (World) —

    the world to which the PingCache belongs



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# File 'lib/dynflow/dispatcher/client_dispatcher.rb', line 57

def initialize(world, max_age = DEFAULT_MAX_AGE)
  @world = world
  @max_age = max_age
  @executor = {}
end

Class Method Details

.format_time(time = Time.now) ⇒ String

Formats time into a string

Parameters:

  • time (Time) (defaults to: Time.now) —

    the time to format

Returns:

  • (String) —

    the formatted time



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# File 'lib/dynflow/dispatcher/client_dispatcher.rb', line 44

def self.format_time(time = Time.now)
  time.strftime(TIME_FORMAT)
end

.load_time(time) ⇒ Time

Parses time from a string

Parameters:

  • time (String) —

    the time string to parse

Returns:

  • (Time) —

    the parsed time



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# File 'lib/dynflow/dispatcher/client_dispatcher.rb', line 52

def self.load_time(time)
  Time.strptime(time, TIME_FORMAT)
end

Instance Method Details

#add_record(id, time = Time.now) ⇒ Object

Records when was the world seen into the world’s coordinator record

Parameters:

  • id (String) —

    Id of the world to be added to the cache

  • time (Time) (defaults to: Time.now) —

    Time when was the world last seen



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# File 'lib/dynflow/dispatcher/client_dispatcher.rb', line 67

def add_record(id, time = Time.now)
  record = find_world id
  @executor[id] ||= record.data[:class] == 'Dynflow::Coordinator::ExecutorWorld'
  record.data[:meta].update(:last_seen => self.class.format_time(time))
  @world.coordinator.update_record(record)
end

#executor?(id) ⇒ TrueClass, ...

Looks into the cache whether the world has an executor

Parameters:

  • id (String) —

    Id of the world

Returns:

  • (TrueClass) —

    if the world has an executor

  • (FalseClass) —

    if the world is a client world

  • (NilClass) —

    if unknown



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# File 'lib/dynflow/dispatcher/client_dispatcher.rb', line 80

def executor?(id)
  @executor[id]
end

#fresh_record?(id) ⇒ TrueClass, FalseClass

Loads the coordinator record from the database and checks whether the world was last seen within the time limit

Parameters:

  • id (String) —

    Id of the world to be checked

Returns:

  • (TrueClass) —

    if the world was last seen within the limit

  • (FalseClass) —

    if the world was last seen after the limit passed



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# File 'lib/dynflow/dispatcher/client_dispatcher.rb', line 90

def fresh_record?(id)
  record = find_world(id)
  return false if record.nil?
  @executor[id] = record.data[:class] == 'Dynflow::Coordinator::ExecutorWorld'
  time = self.class.load_time(record.data[:meta][:last_seen])
  time >= Time.now - @max_age
end