metamaps--metamaps/config/initializers/rack-attack.rb

class Rack::Attack
  Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new

  # Throttle all requests by IP (60rpm)
  #
  # Key: "rack::attack:#{Time.now.to_i/:period}:req/ip:#{req.ip}"
  # throttle('req/ip', :limit => 300, :period => 5.minutes) do |req|
  #   req.ip # unless req.path.start_with?('/assets')
  # end

  # Throttle POST requests to /login by IP address
  #
  # Key: "rack::attack:#{Time.now.to_i/:period}:logins/ip:#{req.ip}"
  throttle('logins/ip', :limit => 5, :period => 20.seconds) do |req|
    if req.path == '/login' && req.post?
      req.ip
    end
  end

  # Throttle POST requests to /login by email param
  #
  # Key: "rack::attack:#{Time.now.to_i/:period}:logins/email:#{req.email}"
  #
  # Note: This creates a problem where a malicious user could intentionally
  # throttle logins for another user and force their login requests to be
  # denied, but that's not very common and shouldn't happen to you. (Knock
  # on wood!)
  throttle("logins/email", :limit => 5, :period => 20.seconds) do |req|
    if req.path == '/login' && req.post?
      # return the email if present, nil otherwise
      req.params['email'].presence
    end
  end

  throttle('load_url_title/req/5mins/ip', :limit => 300, :period => 5.minutes) do |req|
    req.ip if req.path == 'hacks/load_url_title'
  end
  throttle('load_url_title/req/1s/ip', :limit => 5, :period => 1.second) do |req|
    # If the return value is truthy, the cache key for the return value
    # is incremented and compared with the limit. In this case:
    #   "rack::attack:#{Time.now.to_i/1.second}:load_url_title/req/ip:#{req.ip}"
    #
    # If falsy, the cache key is neither incremented nor checked.

    req.ip if req.path == 'hacks/load_url_title'
  end

  self.throttled_response = lambda do |env|
		now = Time.now
		match_data = env['rack.attack.match_data']
    period = match_data[:period]
    limit = match_data[:limit]

		headers = {
      'X-RateLimit-Limit' => limit.to_s,
			'X-RateLimit-Remaining' => '0',
			'X-RateLimit-Reset' => (now + (period - now.to_i % period)).to_s
		}

    [429, headers, ['']]
  end
end