61 lines
2.1 KiB
Ruby
61 lines
2.1 KiB
Ruby
# frozen_string_literal: true
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module CrawlerDetection
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WAYBACK_MACHINE_URL = "web.archive.org"
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def self.to_matcher(string, type: nil)
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escaped = string.split('|').map { |agent| Regexp.escape(agent) }.join('|')
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if type == :real && Rails.env == "test"
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# we need this bypass so we properly render views
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escaped << "|Rails Testing"
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end
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Regexp.new(escaped, Regexp::IGNORECASE)
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end
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def self.crawler?(user_agent, via_header = nil)
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return true if user_agent.nil? || via_header&.include?(WAYBACK_MACHINE_URL)
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# this is done to avoid regenerating regexes
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@non_crawler_matchers ||= {}
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@matchers ||= {}
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possibly_real = (@non_crawler_matchers[SiteSetting.non_crawler_user_agents] ||= to_matcher(SiteSetting.non_crawler_user_agents, type: :real))
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if user_agent.match?(possibly_real)
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known_bots = (@matchers[SiteSetting.crawler_user_agents] ||= to_matcher(SiteSetting.crawler_user_agents))
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if user_agent.match?(known_bots)
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bypass = (@matchers[SiteSetting.crawler_check_bypass_agents] ||= to_matcher(SiteSetting.crawler_check_bypass_agents))
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!user_agent.match?(bypass)
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else
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false
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end
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else
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true
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end
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end
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# Given a user_agent that returns true from crawler?, should its request be allowed?
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def self.allow_crawler?(user_agent)
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return true if SiteSetting.whitelisted_crawler_user_agents.blank? &&
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SiteSetting.blacklisted_crawler_user_agents.blank?
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@whitelisted_matchers ||= {}
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@blacklisted_matchers ||= {}
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if SiteSetting.whitelisted_crawler_user_agents.present?
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whitelisted = @whitelisted_matchers[SiteSetting.whitelisted_crawler_user_agents] ||= to_matcher(SiteSetting.whitelisted_crawler_user_agents)
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!user_agent.nil? && user_agent.match?(whitelisted)
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else
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blacklisted = @blacklisted_matchers[SiteSetting.blacklisted_crawler_user_agents] ||= to_matcher(SiteSetting.blacklisted_crawler_user_agents)
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user_agent.nil? || !user_agent.match?(blacklisted)
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end
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end
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def self.is_blocked_crawler?(user_agent)
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crawler?(user_agent) && !allow_crawler?(user_agent)
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end
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end
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