# module WEBrick::AccessLog

`AccessLog` provides logging to various files in various formats.

Multiple logs may be written to at the same time:

    access_log = [
      [$stderr, WEBrick::AccessLog::COMMON_LOG_FORMAT],
      [$stderr, WEBrick::AccessLog::REFERER_LOG_FORMAT],
    ]

    server = WEBrick::HTTPServer.new :AccessLog => access_log

Custom log formats may be defined. `WEBrick::AccessLog` provides a subset of the formatting from Apache's mod_log_config httpd.apache.org/docs/mod/mod_log_config.html#formats. See AccessLog::setup_params for a list of supported options

### Constants

AGENT_LOG_FORMAT

  User-Agent `Log` Format

CLF

  Short alias for Common `Log` Format

CLF_TIME_FORMAT

  The Common `Log` Format's time format

COMBINED_LOG_FORMAT

  Combined `Log` Format

COMMON_LOG_FORMAT

  Common `Log` Format

REFERER_LOG_FORMAT

  Referer `Log` Format

### Public Instance Methods

escape(data) click to toggle source

Escapes control characters in `data`

    # File lib/webrick/accesslog.rb, line 151
    def escape(data)
      if data.tainted?
        data.gsub(/[[:cntrl:]\\]+/) {$&.dump[1...-1]}.untaint
      else
        data
      end
    end

format(format_string, params) click to toggle source

Formats `params` according to `format_string` which is described in setup_params.

    # File lib/webrick/accesslog.rb, line 123
    def format(format_string, params)
      format_string.gsub(/\%(?:\{(.*?)\})?>?([a-zA-Z%])/){
         param, spec = $1, $2
         case spec[0]
         when ?e, ?i, ?n, ?o
           raise AccessLogError,
             "parameter is required for \"#{spec}\"" unless param
           (param = params[spec][param]) ? escape(param) : "-"
         when ?t
           params[spec].strftime(param || CLF_TIME_FORMAT)
         when ?p
           case param
           when 'remote'
             escape(params["i"].peeraddr[1].to_s)
           else
             escape(params["p"].to_s)
           end
         when ?%
           "%"
         else
           escape(params[spec].to_s)
         end
      }
    end

setup_params(config, req, res) click to toggle source

This format specification is a subset of mod_log_config of Apache:

%a

  Remote IP address

%b

  Total response size

%e{variable}

  Given variable in `ENV`

%f

  Response filename

%h

  Remote host name

%{header}i

  Given request header

%l

  Remote logname, always “-”

%m

  Request method

%{attr}n

  Given request attribute from `req.attributes`

%{header}o

  Given response header

%p

  Server's request port

%{format}p

  The canonical port of the server serving the request or the actual port or the client's actual port. Valid formats are canonical, local or remote.

%q

  Request query string

%r

  First line of the request

%s

  Request status

%t

  `Time` the request was received

%T

  `Time` taken to process the request

%u

  Remote user from auth

%U

  Unparsed `URI`

%%

  Literal %

    # File lib/webrick/accesslog.rb, line 95
    def setup_params(config, req, res)
      params = Hash.new("")
      params["a"] = req.peeraddr[3]
      params["b"] = res.sent_size
      params["e"] = ENV
      params["f"] = res.filename || ""
      params["h"] = req.peeraddr[2]
      params["i"] = req
      params["l"] = "-"
      params["m"] = req.request_method
      params["n"] = req.attributes
      params["o"] = res
      params["p"] = req.port
      params["q"] = req.query_string
      params["r"] = req.request_line.sub(/\x0d?\x0a\z/o, '')
      params["s"] = res.status       # won't support "%>s"
      params["t"] = req.request_time
      params["T"] = Time.now - req.request_time
      params["u"] = req.user || "-"
      params["U"] = req.unparsed_uri
      params["v"] = config[:ServerName]
      params
    end