forgeplus/app/services/token_bucket_rate_limiter.rb

class TokenBucketRateLimiter
	def initialize(user_id,rate, capacity)
		@rate = rate  # 令牌发放速率（每秒发放的令牌数）
		@capacity = capacity  # 令牌桶容量
		@redis = $redis_cache
		@key = "#{user_id}:TokenBucket"
	end

	def refill
		now = Time.now.to_f * 1000
		tokens = $redis_cache.hget(@key, 'tokens')
		timestamp = $redis_cache.hget(@key, 'timestamp')

		if tokens.nil?
		tokens = @capacity
		timestamp = now
		else
		tokens = [@capacity, tokens.to_i + (now - timestamp.to_f) * @rate / 1000].min
		timestamp = now
		end

		$redis_cache.hset(@key, 'tokens', tokens)
		$redis_cache.hset(@key, 'timestamp', timestamp)
	end

	def allow_request
		refill
		tokens = @redis.hget(@key, 'tokens')
		if !tokens.nil? && tokens.to_i >= 1
			@redis.hset(@key, 'tokens', tokens.to_i - 1)
			return true
		end
		false
	end
end

=begin
	#测试通过
	limiter = TokenBucketRateLimiter.new(user_id,10, 40) # 设置令牌发放速率为10，令牌桶容量为40
	30.times do
		if limiter.allow_request
			puts "Allow"
		else
			puts "Reject"
		end
	end

=end