1 files changed, 728 insertions, 0 deletions
diff --git a/lib/rbot/httputil.rb b/lib/rbot/httputil.rb
new file mode 100644
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--- /dev/null
+++ b/lib/rbot/httputil.rb
@@ -0,0 +1,728 @@
+# encoding: UTF-8
+#-- vim:sw=2:et
+#++
+#
+# :title: rbot HTTP provider
+#
+# Author:: Tom Gilbert <tom@linuxbrit.co.uk>
+# Author:: Giuseppe "Oblomov" Bilotta <giuseppe.bilotta@gmail.com>
+# Author:: Dmitry "jsn" Kim <dmitry point kim at gmail point com>
+
+require 'resolv'
+require 'net/http'
+require 'cgi'
+
+begin
+  require 'nokogiri'
+rescue LoadError => e
+  error "No nokogiri library found, some features might not be available!"
+end
+
+# To handle Gzipped pages
+require 'stringio'
+require 'zlib'
+
+module ::Net
+  class HTTPResponse
+    attr_accessor :no_cache
+    unless method_defined? :raw_body
+      alias :raw_body :body
+    end
+
+    def body_charset(str=self.raw_body)
+      ctype = self['content-type'] || 'text/html'
+      return nil unless ctype =~ /^text/i || ctype =~ /x(ht)?ml/i
+
+      charsets = ['ISO-8859-1'] # should be in config
+
+      if ctype.match(/charset=["']?([^\s"']+)["']?/i)
+        charsets << $1
+        debug "charset #{charsets.last} added from header"
+      end
+
+      # str might be invalid utf-8 that will crash on the pattern match:
+      str.encode!('UTF-8', 'UTF-8', :invalid => :replace)
+      case str
+      when /<\?xml\s[^>]*encoding=['"]([^\s"'>]+)["'][^>]*\?>/i
+        charsets << $1
+        debug "xml charset #{charsets.last} added from xml pi"
+      when /<(meta\s[^>]*http-equiv=["']?Content-Type["']?[^>]*)>/i
+        meta = $1
+        if meta =~ /charset=['"]?([^\s'";]+)['"]?/
+          charsets << $1
+          debug "html charset #{charsets.last} added from meta"
+        end
+      end
+      return charsets.uniq
+    end
+
+    def body_to_utf(str)
+      charsets = self.body_charset(str) or return str
+
+      charsets.reverse_each do |charset|
+        begin
+          debug "try decoding using #{charset}"
+          str.force_encoding(charset)
+          tmp = str.encode('UTF-16le', :invalid => :replace, :replace => '').encode('UTF-8')
+          if tmp
+            str = tmp
+            break
+          end
+        rescue
+          error 'failed to use encoding'
+          error $!
+        end
+      end
+
+      return str
+    end
+
+    def decompress_body(str)
+      method = self['content-encoding']
+      case method
+      when nil
+        return str
+      when /gzip/ # Matches gzip, x-gzip, and the non-rfc-compliant gzip;q=\d sent by some servers
+        debug "gunzipping body"
+        begin
+          return Zlib::GzipReader.new(StringIO.new(str)).read
+        rescue Zlib::Error => e
+          # If we can't unpack the whole stream (e.g. because we're doing a
+          # partial read
+          debug "full gunzipping failed (#{e}), trying to recover as much as possible"
+          ret = ''
+          ret.force_encoding(Encoding::ASCII_8BIT)
+          begin
+            Zlib::GzipReader.new(StringIO.new(str)).each_byte { |byte|
+              ret << byte
+            }
+          rescue
+          end
+          return ret
+        end
+      when 'deflate'
+        debug "inflating body"
+        # From http://www.koders.com/ruby/fid927B4382397E5115AC0ABE21181AB5C1CBDD5C17.aspx?s=thread:
+        # -MAX_WBITS stops zlib from looking for a zlib header
+        inflater = Zlib::Inflate.new(-Zlib::MAX_WBITS)
+        begin
+          return inflater.inflate(str)
+        rescue Zlib::Error => e
+          raise e
+          # TODO
+          # debug "full inflation failed (#{e}), trying to recover as much as possible"
+        end
+      when /^(?:iso-8859-\d+|windows-\d+|utf-8|utf8)$/i
+        # B0rked servers (Freshmeat being one of them) sometimes return the charset
+        # in the content-encoding; in this case we assume that the document has
+        # a standard content-encoding
+        old_hsh = self.to_hash
+        self['content-type']= self['content-type']+"; charset="+method.downcase
+        warning "Charset vs content-encoding confusion, trying to recover: from\n#{old_hsh.pretty_inspect}to\n#{self.to_hash.pretty_inspect}"
+        return str
+      else
+        debug self.to_hash
+        raise "Unhandled content encoding #{method}"
+      end
+    end
+
+    def cooked_body
+      return self.body_to_utf(self.decompress_body(self.raw_body))
+    end
+
+    # Read chunks from the body until we have at least _size_ bytes, yielding
+    # the partial text at each chunk. Return the partial body.
+    def partial_body(size=0, &block)
+
+      partial = String.new
+
+      if @read
+        debug "using body() as partial"
+        partial = self.body
+        yield self.body_to_utf(self.decompress_body(partial)) if block_given?
+      else
+        debug "disabling cache"
+        self.no_cache = true
+        self.read_body { |chunk|
+          partial << chunk
+          yield self.body_to_utf(self.decompress_body(partial)) if block_given?
+          break if size and size > 0 and partial.length >= size
+        }
+      end
+
+      return self.body_to_utf(self.decompress_body(partial))
+    end
+
+    def xpath(path)
+      document = Nokogiri::HTML.parse(self.body)
+      document.xpath(path)
+    end
+
+    def to_json
+      JSON::parse(self.body)
+    end
+  end
+end
+
+module ::Irc
+module Utils
+
+# class for making http requests easier (mainly for plugins to use)
+# this class can check the bot proxy configuration to determine if a proxy
+# needs to be used, which includes support for per-url proxy configuration.
+class HttpUtil
+    Bot::Config.register Bot::Config::IntegerValue.new('http.read_timeout',
+      :default => 10, :desc => "Default read timeout for HTTP connections")
+    Bot::Config.register Bot::Config::IntegerValue.new('http.open_timeout',
+      :default => 20, :desc => "Default open timeout for HTTP connections")
+    Bot::Config.register Bot::Config::BooleanValue.new('http.use_proxy',
+      :default => false, :desc => "should a proxy be used for HTTP requests?")
+    Bot::Config.register Bot::Config::StringValue.new('http.proxy_uri', :default => false,
+      :desc => "Proxy server to use for HTTP requests (URI, e.g http://proxy.host:port)")
+    Bot::Config.register Bot::Config::StringValue.new('http.proxy_user',
+      :default => nil,
+      :desc => "User for authenticating with the http proxy (if required)")
+    Bot::Config.register Bot::Config::StringValue.new('http.proxy_pass',
+      :default => nil,
+      :desc => "Password for authenticating with the http proxy (if required)")
+    Bot::Config.register Bot::Config::ArrayValue.new('http.proxy_include',
+      :default => [],
+      :desc => "List of regexps to check against a URI's hostname/ip to see if we should use the proxy to access this URI. All URIs are proxied by default if the proxy is set, so this is only required to re-include URIs that might have been excluded by the exclude list. e.g. exclude /.*\.foo\.com/, include bar\.foo\.com")
+    Bot::Config.register Bot::Config::ArrayValue.new('http.proxy_exclude',
+      :default => [],
+      :desc => "List of regexps to check against a URI's hostname/ip to see if we should use avoid the proxy to access this URI and access it directly")
+    Bot::Config.register Bot::Config::IntegerValue.new('http.max_redir',
+      :default => 5,
+      :desc => "Maximum number of redirections to be used when getting a document")
+    Bot::Config.register Bot::Config::IntegerValue.new('http.expire_time',
+      :default => 60,
+      :desc => "After how many minutes since last use a cached document is considered to be expired")
+    Bot::Config.register Bot::Config::IntegerValue.new('http.max_cache_time',
+      :default => 60*24,
+      :desc => "After how many minutes since first use a cached document is considered to be expired")
+    Bot::Config.register Bot::Config::BooleanValue.new('http.no_expire_cache',
+      :default => false,
+      :desc => "Set this to true if you want the bot to never expire the cached pages")
+    Bot::Config.register Bot::Config::IntegerValue.new('http.info_bytes',
+      :default => 8192,
+      :desc => "How many bytes to download from a web page to find some information. Set to 0 to let the bot download the whole page.")
+
+  class CachedObject
+    attr_accessor :response, :last_used, :first_used, :count, :expires, :date
+
+    def self.maybe_new(resp)
+      debug "maybe new #{resp}"
+      return nil if resp.no_cache
+      return nil unless Net::HTTPOK === resp ||
+      Net::HTTPMovedPermanently === resp ||
+      Net::HTTPFound === resp ||
+      Net::HTTPPartialContent === resp
+
+      cc = resp['cache-control']
+      return nil if cc && (cc =~ /no-cache/i)
+
+      date = Time.now
+      if d = resp['date']
+        date = Time.httpdate(d)
+      end
+
+      return nil if resp['expires'] && (Time.httpdate(resp['expires']) < date)
+
+      debug "creating cache obj"
+
+      self.new(resp)
+    end
+
+    def use
+      now = Time.now
+      @first_used = now if @count == 0
+      @last_used = now
+      @count += 1
+    end
+
+    def expired?
+      debug "checking expired?"
+      if cc = self.response['cache-control'] && cc =~ /must-revalidate/
+        return true
+      end
+      return self.expires < Time.now
+    end
+
+    def setup_headers(hdr)
+      hdr['if-modified-since'] = self.date.rfc2822
+
+      debug "ims == #{hdr['if-modified-since']}"
+
+      if etag = self.response['etag']
+        hdr['if-none-match'] = etag
+        debug "etag: #{etag}"
+      end
+    end
+
+    def revalidate(resp = self.response)
+      @count = 0
+      self.use
+      self.date = resp.key?('date') ? Time.httpdate(resp['date']) : Time.now
+
+      cc = resp['cache-control']
+      if cc && (cc =~ /max-age=(\d+)/)
+        self.expires = self.date + $1.to_i
+      elsif resp.key?('expires')
+        self.expires = Time.httpdate(resp['expires'])
+      elsif lm = resp['last-modified']
+        delta = self.date - Time.httpdate(lm)
+        delta = 10 if delta <= 0
+        delta /= 5
+        self.expires = self.date + delta
+      else
+        self.expires = self.date + 300
+      end
+      # self.expires = Time.now + 10 # DEBUG
+      debug "expires on #{self.expires}"
+
+      return true
+    end
+
+    private
+    def initialize(resp)
+      @response = resp
+      begin
+        self.revalidate
+        self.response.raw_body
+      rescue Exception => e
+        error e
+        raise e
+      end
+    end
+  end
+
+  # Create the HttpUtil instance, associating it with Bot _bot_
+  #
+  def initialize(bot)
+    @bot = bot
+    @cache = Hash.new
+    @headers = {
+      'Accept-Charset' => 'utf-8;q=1.0, *;q=0.8',
+      'Accept-Encoding' => 'gzip;q=1, deflate;q=1, identity;q=0.8, *;q=0.2',
+      'User-Agent' =>
+        "rbot http util #{$version} (#{Irc::Bot::SOURCE_URL})"
+    }
+    debug "starting http cache cleanup timer"
+    @timer = @bot.timer.add(300) {
+      self.remove_stale_cache unless @bot.config['http.no_expire_cache']
+    }
+  end
+
+  # Clean up on HttpUtil unloading, by stopping the cache cleanup timer.
+  def cleanup
+    debug 'stopping http cache cleanup timer'
+    @bot.timer.remove(@timer)
+  end
+
+  # This method checks if a proxy is required to access _uri_, by looking at
+  # the values of config values +http.proxy_include+ and +http.proxy_exclude+.
+  #
+  # Each of these config values, if set, should be a Regexp the server name and
+  # IP address should be checked against.
+  #
+  def proxy_required(uri)
+    use_proxy = true
+    if @bot.config["http.proxy_exclude"].empty? && @bot.config["http.proxy_include"].empty?
+      return use_proxy
+    end
+
+    list = [uri.host]
+    begin
+      list.concat Resolv.getaddresses(uri.host)
+    rescue StandardError => err
+      warning "couldn't resolve host uri.host"
+    end
+
+    unless @bot.config["http.proxy_exclude"].empty?
+      re = @bot.config["http.proxy_exclude"].collect{|r| Regexp.new(r)}
+      re.each do |r|
+        list.each do |item|
+          if r.match(item)
+            use_proxy = false
+            break
+          end
+        end
+      end
+    end
+    unless @bot.config["http.proxy_include"].empty?
+      re = @bot.config["http.proxy_include"].collect{|r| Regexp.new(r)}
+      re.each do |r|
+        list.each do |item|
+          if r.match(item)
+            use_proxy = true
+            break
+          end
+        end
+      end
+    end
+    debug "using proxy for uri #{uri}?: #{use_proxy}"
+    return use_proxy
+  end
+
+  # _uri_:: URI to create a proxy for
+  #
+  # Return a net/http Proxy object, configured for proxying based on the
+  # bot's proxy configuration. See proxy_required for more details on this.
+  #
+  def get_proxy(uri, options = {})
+    opts = {
+      :read_timeout => @bot.config["http.read_timeout"],
+      :open_timeout => @bot.config["http.open_timeout"]
+    }.merge(options)
+
+    proxy = nil
+    proxy_host = nil
+    proxy_port = nil
+    proxy_user = nil
+    proxy_pass = nil
+
+    if @bot.config["http.use_proxy"]
+      if (ENV['http_proxy'])
+        proxy = URI.parse ENV['http_proxy'] rescue nil
+      end
+      if (@bot.config["http.proxy_uri"])
+        proxy = URI.parse @bot.config["http.proxy_uri"] rescue nil
+      end
+      if proxy
+        debug "proxy is set to #{proxy.host} port #{proxy.port}"
+        if proxy_required(uri)
+          proxy_host = proxy.host
+          proxy_port = proxy.port
+          proxy_user = @bot.config["http.proxy_user"]
+          proxy_pass = @bot.config["http.proxy_pass"]
+        end
+      end
+    end
+
+    h = Net::HTTP.new(uri.host, uri.port, proxy_host, proxy_port, proxy_user, proxy_pass)
+    h.use_ssl = true if uri.scheme == "https"
+
+    h.read_timeout = opts[:read_timeout]
+    h.open_timeout = opts[:open_timeout]
+    return h
+  end
+
+  # Internal method used to hanlde response _resp_ received when making a
+  # request for URI _uri_.
+  #
+  # It follows redirects, optionally yielding them if option :yield is :all.
+  #
+  # Also yields and returns the final _resp_.
+  #
+  def handle_response(uri, resp, opts, &block) # :yields: resp
+    if Net::HTTPRedirection === resp && opts[:max_redir] >= 0
+      if resp.key?('location')
+        raise 'Too many redirections' if opts[:max_redir] <= 0
+        yield resp if opts[:yield] == :all && block_given?
+        # some servers actually provide unescaped location, e.g.
+        # http://ulysses.soup.io/post/60734021/Image%20curve%20ball
+        # rediects to something like
+        # http://ulysses.soup.io/post/60734021/Image curve ball?sessid=8457b2a3752085cca3fb1d79b9965446
+        # causing the URI parser to (obviously) complain. We cannot just
+        # escape blindly, as this would make a mess of already-escaped
+        # locations, so we only do it if the URI.parse fails
+        loc = resp['location']
+        escaped = false
+        debug "redirect location: #{loc.inspect}"
+        begin
+          new_loc = URI.join(uri.to_s, loc) rescue URI.parse(loc)
+        rescue
+          if escaped
+            raise $!
+          else
+            loc = URI.escape(loc)
+            escaped = true
+            debug "escaped redirect location: #{loc.inspect}"
+            retry
+          end
+        end
+        new_opts = opts.dup
+        new_opts[:max_redir] -= 1
+        case opts[:method].to_s.downcase.intern
+        when :post, :"net::http::post"
+          new_opts[:method] = :get
+        end
+        if resp['set-cookie']
+          debug "set cookie request for #{resp['set-cookie']}"
+          cookie, cookie_flags = (resp['set-cookie']+'; ').split('; ', 2)
+          domain = uri.host
+          cookie_flags.scan(/(\S+)=(\S+);/) { |key, val|
+            if key.intern == :domain
+              domain = val
+              break
+            end
+          }
+          debug "cookie domain #{domain} / #{new_loc.host}"
+          if new_loc.host.rindex(domain) == new_loc.host.length - domain.length
+            debug "setting cookie"
+            new_opts[:headers] ||= Hash.new
+            new_opts[:headers]['Cookie'] = cookie
+          else
+            debug "cookie is for another domain, ignoring"
+          end
+        end
+        debug "following the redirect to #{new_loc}"
+        return get_response(new_loc, new_opts, &block)
+      else
+        warning ":| redirect w/o location?"
+      end
+    end
+    class << resp
+      undef_method :body
+      alias :body :cooked_body
+    end
+    unless resp['content-type']
+      debug "No content type, guessing"
+      resp['content-type'] =
+        case resp['x-rbot-location']
+        when /.html?$/i
+          'text/html'
+        when /.xml$/i
+          'application/xml'
+        when /.xhtml$/i
+          'application/xml+xhtml'
+        when /.(gif|png|jpe?g|jp2|tiff?)$/i
+          "image/#{$1.sub(/^jpg$/,'jpeg').sub(/^tif$/,'tiff')}"
+        else
+          'application/octetstream'
+        end
+    end
+    if block_given?
+      yield(resp)
+    else
+      # Net::HTTP wants us to read the whole body here
+      resp.raw_body
+    end
+    return resp
+  end
+
+  # _uri_::     uri to query (URI object or String)
+  #
+  # Generic http transaction method. It will return a Net::HTTPResponse
+  # object or raise an exception
+  #
+  # If a block is given, it will yield the response (see :yield option)
+  #
+  # Currently supported _options_:
+  #
+  # method::     request method [:get (default), :post or :head]
+  # open_timeout::     open timeout for the proxy
+  # read_timeout::     read timeout for the proxy
+  # cache::            should we cache results?
+  # yield::      if :final [default], calls the block for the response object;
+  #              if :all, call the block for all intermediate redirects, too
+  # max_redir::  how many redirects to follow before raising the exception
+  #              if -1, don't follow redirects, just return them
+  # range::      make a ranged request (usually GET). accepts a string
+  #              for HTTP/1.1 "Range:" header (i.e. "bytes=0-1000")
+  # body::       request body (usually for POST requests)
+  # headers::    additional headers to be set for the request. Its value must
+  #              be a Hash in the form { 'Header' => 'value' }
+  #
+  def get_response(uri_or_s, options = {}, &block) # :yields: resp
+    uri = uri_or_s.kind_of?(URI) ? uri_or_s : URI.parse(uri_or_s.to_s)
+    unless URI::HTTP === uri
+      if uri.scheme
+        raise "#{uri.scheme.inspect} URI scheme is not supported"
+      else
+        raise "don't know what to do with #{uri.to_s.inspect}"
+      end
+    end
+
+    opts = {
+      :max_redir => @bot.config['http.max_redir'],
+      :yield => :final,
+      :cache => true,
+      :method => :GET
+    }.merge(options)
+
+    req_class = case opts[:method].to_s.downcase.intern
+                when :head, :"net::http::head"
+                  opts[:max_redir] = -1
+                  Net::HTTP::Head
+                when :get, :"net::http::get"
+                  Net::HTTP::Get
+                when :post, :"net::http::post"
+                  opts[:cache] = false
+                  opts[:body] or raise 'post request w/o a body?'
+                  warning "refusing to cache POST request" if options[:cache]
+                  Net::HTTP::Post
+                else
+                  warning "unsupported method #{opts[:method]}, doing GET"
+                  Net::HTTP::Get
+                end
+
+    if req_class != Net::HTTP::Get && opts[:range]
+      warning "can't request ranges for #{req_class}"
+      opts.delete(:range)
+    end
+
+    cache_key = "#{opts[:range]}|#{req_class}|#{uri.to_s}"
+
+    if req_class != Net::HTTP::Get && req_class != Net::HTTP::Head
+      if opts[:cache]
+        warning "can't cache #{req_class.inspect} requests, working w/o cache"
+        opts[:cache] = false
+      end
+    end
+
+    debug "get_response(#{uri}, #{opts.inspect})"
+
+    cached = @cache[cache_key]
+
+    if opts[:cache] && cached
+      debug "got cached"
+      if !cached.expired?
+        debug "using cached"
+        cached.use
+        return handle_response(uri, cached.response, opts, &block)
+      end
+    end
+
+    headers = @headers.dup.merge(opts[:headers] || {})
+    headers['Range'] = opts[:range] if opts[:range]
+    headers['Authorization'] = opts[:auth_head] if opts[:auth_head]
+
+    if opts[:cache] && cached && (req_class == Net::HTTP::Get)
+      cached.setup_headers headers
+    end
+
+    req = req_class.new(uri.request_uri, headers)
+    if uri.user && uri.password
+      req.basic_auth(uri.user, uri.password)
+      opts[:auth_head] = req['Authorization']
+    end
+    req.body = opts[:body] if req_class == Net::HTTP::Post
+    debug "prepared request: #{req.to_hash.inspect}"
+
+    begin
+      get_proxy(uri, opts).start do |http|
+        http.request(req) do |resp|
+          resp['x-rbot-location'] = uri.to_s
+          if Net::HTTPNotModified === resp
+            debug "not modified"
+            begin
+              cached.revalidate(resp)
+            rescue Exception => e
+              error e
+            end
+            debug "reusing cached"
+            resp = cached.response
+          elsif Net::HTTPServerError === resp || Net::HTTPClientError === resp
+            debug "http error, deleting cached obj" if cached
+            @cache.delete(cache_key)
+          end
+
+          begin
+            return handle_response(uri, resp, opts, &block)
+          ensure
+            if cached = CachedObject.maybe_new(resp) rescue nil
+              debug "storing to cache"
+              @cache[cache_key] = cached
+            end
+          end
+        end
+      end
+    rescue Exception => e
+      error e
+      raise e.message
+    end
+  end
+
+  # _uri_::     uri to query (URI object or String)
+  #
+  # Simple GET request, returns (if possible) response body following redirs
+  # and caching if requested, yielding the actual response(s) to the optional
+  # block. See get_response for details on the supported _options_
+  #
+  def get(uri, options = {}, &block) # :yields: resp
+    begin
+      resp = get_response(uri, options, &block)
+      raise "http error: #{resp}" unless Net::HTTPOK === resp ||
+        Net::HTTPPartialContent === resp
+      if options[:resp]
+        return resp
+      else
+        return resp.body
+      end
+    rescue Exception => e
+      error e
+    end
+    return nil
+  end
+
+  # _uri_::     uri to query (URI object or String)
+  #
+  # Simple HEAD request, returns (if possible) response head following redirs
+  # and caching if requested, yielding the actual response(s) to the optional
+  # block. See get_response for details on the supported _options_
+  #
+  def head(uri, options = {}, &block) # :yields: resp
+    opts = {:method => :head}.merge(options)
+    begin
+      resp = get_response(uri, opts, &block)
+      # raise "http error #{resp}" if Net::HTTPClientError === resp ||
+      #   Net::HTTPServerError == resp
+      return resp
+    rescue Exception => e
+      error e
+    end
+    return nil
+  end
+
+  # _uri_::     uri to query (URI object or String)
+  # _data_::    body of the POST
+  #
+  # Simple POST request, returns (if possible) response following redirs and
+  # caching if requested, yielding the response(s) to the optional block. See
+  # get_response for details on the supported _options_
+  #
+  def post(uri, data, options = {}, &block) # :yields: resp
+    opts = {:method => :post, :body => data, :cache => false}.merge(options)
+    begin
+      resp = get_response(uri, opts, &block)
+      raise 'http error' unless Net::HTTPOK === resp or Net::HTTPCreated === resp
+      return resp
+    rescue Exception => e
+      error e
+    end
+    return nil
+  end
+
+  # _uri_::     uri to query (URI object or String)
+  # _nbytes_::  number of bytes to get
+  #
+  # Partial GET request, returns (if possible) the first _nbytes_ bytes of the
+  # response body, following redirs and caching if requested, yielding the
+  # actual response(s) to the optional block. See get_response for details on
+  # the supported _options_
+  #
+  def get_partial(uri, nbytes = @bot.config['http.info_bytes'], options = {}, &block) # :yields: resp
+    opts = {:range => "bytes=0-#{nbytes}"}.merge(options)
+    return get(uri, opts, &block)
+  end
+
+  def remove_stale_cache
+    debug "Removing stale cache"
+    now = Time.new
+    max_last = @bot.config['http.expire_time'] * 60
+    max_first = @bot.config['http.max_cache_time'] * 60
+    debug "#{@cache.size} pages before"
+    begin
+      @cache.reject! { |k, val|
+        (now - val.last_used > max_last) || (now - val.first_used > max_first)
+      }
+    rescue => e
+      error "Failed to remove stale cache: #{e.pretty_inspect}"
+    end
+    debug "#{@cache.size} pages after"
+  end
+
+end
+end
+end