debian-mirror-gitlab/lib/gitlab/action_rate_limiter.rb
2018-12-13 13:39:08 +05:30

49 lines
1.4 KiB
Ruby

# frozen_string_literal: true
module Gitlab
# This class implements a simple rate limiter that can be used to throttle
# certain actions. Unlike Rack Attack and Rack::Throttle, which operate at
# the middleware level, this can be used at the controller level.
class ActionRateLimiter
TIME_TO_EXPIRE = 60 # 1 min
attr_accessor :action, :expiry_time
def initialize(action:, expiry_time: TIME_TO_EXPIRE)
@action = action
@expiry_time = expiry_time
end
# Increments the given cache key and increments the value by 1 with the
# given expiration time. Returns the incremented value.
#
# key - An array of ActiveRecord instances
def increment(key)
value = 0
Gitlab::Redis::Cache.with do |redis|
cache_key = action_key(key)
value = redis.incr(cache_key)
redis.expire(cache_key, expiry_time) if value == 1
end
value
end
# Increments the given key and returns true if the action should
# be throttled.
#
# key - An array of ActiveRecord instances
# threshold_value - The maximum number of times this action should occur in the given time interval
def throttled?(key, threshold_value)
self.increment(key) > threshold_value
end
private
def action_key(key)
serialized = key.map { |obj| "#{obj.class.model_name.to_s.underscore}:#{obj.id}" }.join(":")
"action_rate_limiter:#{action}:#{serialized}"
end
end
end