Class: DistributedRateQueue

Inherits:
Object
  • Object
show all
Defined in:
lib/limiter/distributed_rate_queue.rb

Overview

medium.com/@jaimersonn/throttling-api-calls-in-a-distributed-environment-76d2789a796d

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(redis_urls:, key:, rate: 60, interval: 60) ⇒ DistributedRateQueue

Returns a new instance of DistributedRateQueue.



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# File 'lib/limiter/distributed_rate_queue.rb', line 7

def initialize(redis_urls:, key:, rate: 60, interval: 60)
  @lock_duration = ((interval / rate.to_f) * 1000).to_i # Redlock deals with miliseconds
  @lock_manager = Redlock::Client.new(redis_urls)
  @key = key
end

Instance Attribute Details

#key ⇒ Object (readonly)

Returns the value of attribute key.



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# File 'lib/limiter/distributed_rate_queue.rb', line 5

def key
  @key
end

#lock_duration ⇒ Object (readonly)

Returns the value of attribute lock_duration.



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# File 'lib/limiter/distributed_rate_queue.rb', line 5

def lock_duration
  @lock_duration
end

#lock_manager ⇒ Object (readonly)

Returns the value of attribute lock_manager.



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# File 'lib/limiter/distributed_rate_queue.rb', line 5

def lock_manager
  @lock_manager
end

Instance Method Details

#shift(&block) ⇒ Object 



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# File 'lib/limiter/distributed_rate_queue.rb', line 13

def shift(&block)
  if lock_manager.lock(key, lock_duration)
    # puts "timestamp: #{Time.now.to_i}"
    yield
  else
    # Logger.log("Lock not acquired, waiting for next turn...", Process.pid)
    wait_for_next_turn
    shift(&block)
  end
end