lib/clogger.rb

   1 # -*- encoding: binary -*-
   2 class Clogger
   3   VERSION = '0.0.1'
   4
   5   OP_LITERAL = 0
   6   OP_REQUEST = 1
   7   OP_RESPONSE = 2
   8   OP_SPECIAL = 3
   9   OP_EVAL = 4
  10   OP_TIME_LOCAL = 5
  11   OP_TIME_UTC = 6
  12   OP_REQUEST_TIME = 7
  13   OP_TIME = 8
  14   OP_COOKIE = 9
  15
  16   # support nginx variables that are less customizable than our own
  17   ALIASES = {
  18     '$request_time' => '$request_time{3}',
  19     '$time_local' => '$time_local{%d/%b/%Y:%H:%M:%S %z}',
  20     '$msec' => '$time{3}',
  21     '$usec' => '$time{6}',
  22   }
  23
  24   SPECIAL_VARS = {
  25     :body_bytes_sent => 0,
  26     :status => 1,
  27     :request => 2, # REQUEST_METHOD PATH_INFO?QUERY_STRING HTTP_VERSION
  28     :request_length => 3, # env['rack.input'].size
  29     :response_length => 4, # like body_bytes_sent, except "-" instead of "0"
  30     :ip => 5, # HTTP_X_FORWARDED_FOR || REMOTE_ADDR || -
  31     :pid => 6, # getpid()
  32   }
  33
  34 private
  35
  36   CGI_ENV = Regexp.new('\A\$(' <<
  37       %w(remote_addr remote_ident remote_user
  38          path_info query_string script_name
  39          server_name server_port).join('|') << ')\z').freeze
  40
  41   SCAN = /([^$]*)(\$+(?:env\{\w+(?:\.[\w\.]+)?\}|
  42                         e\{[^\}]+\}|
  43                         (?:request_)?time\{\d+\}|
  44                         time_(?:utc|local)\{[^\}]+\}|
  45                         \w*))?([^$]*)/x
  46
  47   def compile_format(str)
  48     rv = []
  49     str.scan(SCAN).each do |pre,tok,post|
  50       rv << [ OP_LITERAL, pre ] if pre && pre != ""
  51
  52       unless tok.nil?
  53         if tok.sub!(/\A(\$+)\$/, '$')
  54           rv << [ OP_LITERAL, $1.dup ]
  55         end
  56
  57         compat = ALIASES[tok] and tok = compat
  58
  59         case tok
  60         when /\A(\$*)\z/
  61           rv << [ OP_LITERAL, $1.dup ]
  62         when /\A\$env\{(\w+(?:\.[\w\.]+))\}\z/
  63           rv << [ OP_REQUEST, $1.freeze ]
  64         when /\A\$e\{([^\}]+)\}\z/
  65           rv << [ OP_EVAL, $1.dup ]
  66         when /\A\$cookie_(\w+)\z/
  67           rv << [ OP_COOKIE, $1.dup.freeze ]
  68         when CGI_ENV, /\A\$(http_\w+)\z/
  69           rv << [ OP_REQUEST, $1.upcase.freeze ]
  70         when /\A\$sent_http_(\w+)\z/
  71           rv << [ OP_RESPONSE, $1.downcase.tr('_','-').freeze ]
  72         when /\A\$time_local\{([^\}]+)\}\z/
  73           rv << [ OP_TIME_LOCAL, $1.dup ]
  74         when /\A\$time_utc\{([^\}]+)\}\z/
  75           rv << [ OP_TIME_UTC, $1.dup ]
  76         when /\A\$time\{(\d+)\}\z/
  77           rv << [ OP_TIME, *usec_conv_pair(tok, $1.to_i) ]
  78         when /\A\$request_time\{(\d+)\}\z/
  79           rv << [ OP_REQUEST_TIME, *usec_conv_pair(tok, $1.to_i) ]
  80         else
  81           tok_sym = tok[1..-1].to_sym
  82           if special_code = SPECIAL_VARS[tok_sym]
  83             rv << [ OP_SPECIAL, special_code ]
  84           else
  85             raise ArgumentError, "unable to make sense of token: #{tok}"
  86           end
  87         end
  88       end
  89
  90       rv << [ OP_LITERAL, post ] if post && post != ""
  91     end
  92
  93     # auto-append a newline
  94     last = rv.last or return rv
  95     op = last.first
  96     if (op == OP_LITERAL && /\n\z/ !~ last.last) || op != OP_LITERAL
  97       rv << [ OP_LITERAL, "\n" ]
  98     end
  99
 100     rv
 101   end
 102
 103   def usec_conv_pair(tok, prec)
 104     if prec == 0
 105       [ "%d", 1 ] # stupid...
 106     elsif prec > 6
 107       raise ArgumentError, "#{tok}: too high precision: #{prec} (max=6)"
 108     else
 109       [ "%d.%0#{prec}d", 10 ** (6 - prec) ]
 110     end
 111   end
 112
 113   def need_response_headers?(fmt_ops)
 114     fmt_ops.any? { |op| OP_RESPONSE == op[0] }
 115   end
 116
 117   def need_wrap_body?(fmt_ops)
 118     fmt_ops.any? do |op|
 119       (OP_REQUEST_TIME == op[0]) || (OP_SPECIAL == op[0] &&
 120         (SPECIAL_VARS[:body_bytes_sent] == op[1] ||
 121          SPECIAL_VARS[:response_length] == op[1]))
 122     end
 123   end
 124
 125 end
 126
 127 require 'clogger/format'
 128
 129 begin
 130   require 'clogger_ext'
 131 rescue LoadError
 132   require 'clogger/pure'
 133 end