blacklist.rb

module Kerrigan
  module Util
    class Blacklist
      def initialize(values)
        update values
      end

      def match?(url)
        p [url, url.class, String === url]
        case url
        when Array
          p :array
          url.any? {|u| match? u }
        when String
          p :string
          url.match(@re).present?
        when URI
          p :uri
          match? url.to_s
        else
          p [:missing, url.class]
          false
        end
      end

      def refresh!(key)
        update self.class.matches_for(key)
      end

      def update(values)
        @re = Regexp.union values
      end

      class << self
        def from_key(key)
          new matches_for(key)
        end

        def matches_for(key)
          db_matches(key) | config_matches(key)
        end

        def db_matches(key)
          doc = MongoMapper.database["config"].find_one(_id: key)
          return [] if doc.nil?
          doc.fetch("string", []) + doc.fetch("regex", []).map {|v| Regexp.new v }
        end

        def config_matches(key)
          Kerrigan.config.value(key.to_s, []) + Kerrigan.config.value("#{key}_re", []).map {|v| Regexp.new v }
        end
      end
    end
  end
end

wtf.txt

> u = Kerrigan::Util::Blacklist.new ["www.amazon.com"]
 => #<Kerrigan::Util::Blacklist:0x5809fa26 @re=/www\.amazon\.com/>

> s = "http://www.amazon.com/kids-hobbies-coins-models/b/ref=sv_t_7/175-7766400-4073802"
 => "http://www.amazon.com/kids-hobbies-coins-models/b/ref=sv_t_7/175-7766400-4073802"

> u.match? s
["http://www.amazon.com/kids-hobbies-coins-models/b/ref=sv_t_7/175-7766400-4073802", String, false]
[:missing, String]
 => false

> String === s
 => true