Class: Pebbles::River::RateLimiter

Inherits:
Object
  • Object
show all
Defined in:
lib/pebbles/river/rate_limiter.rb

Overview

Simple queueless token-bucket limiter.

Instance Method Summary collapse

Constructor Details

#initialize(max_rate, window_seconds) ⇒ RateLimiter

Returns a new instance of RateLimiter.



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# File 'lib/pebbles/river/rate_limiter.rb', line 7

def initialize(max_rate, window_seconds)
  @last_check = Time.now
  @max_rate = @allowance = max_rate
  @window_seconds = window_seconds
end

Instance Method Details

#increment ⇒ Object 



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# File 'lib/pebbles/river/rate_limiter.rb', line 13

def increment
  now = Time.now
  time_passed = now - @last_check
  @last_check = now

  @allowance += time_passed * (@max_rate / @window_seconds)
  if @allowance > @max_rate
    @allowance = @max_rate
  end
  if @allowance < 1
    sleep((1 - @allowance) * (@window_seconds / @max_rate))
    @allowance = 0
  else
    @allowance -= 1
  end
end