Class: Hedra::RateLimiter

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

Overview

Token bucket rate limiter

Instance Method Summary collapse

Constructor Details

#initialize(rate_string) ⇒ RateLimiter

Returns a new instance of RateLimiter.



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# File 'lib/hedra/rate_limiter.rb', line 6

def initialize(rate_string)
  @requests, period = parse_rate(rate_string)
  @period = period_to_seconds(period)
  @tokens = @requests
  @last_refill = Time.now
  @mutex = Mutex.new
end

Instance Method Details

#acquire ⇒ Object 



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# File 'lib/hedra/rate_limiter.rb', line 14

def acquire
  @mutex.synchronize do
    refill_tokens

    if @tokens >= 1
      @tokens -= 1
      return
    end

    # Wait until we have tokens
    sleep_time = @period / @requests
    sleep(sleep_time)
    refill_tokens
    @tokens -= 1
  end
end