JezK
Edit File: patternformatter.rb
# :include: ../rdoc/patternformatter # # == Other Info # # Version:: $Id$ require "log4r/formatter/formatter" require "log4r/GDC" require "log4r/MDC" require "log4r/NDC" module Log4r # See log4r/formatter/patternformatter.rb class PatternFormatter < BasicFormatter # Arguments to sprintf keyed to directive letters<br> # %c - event short name<br> # %C - event fullname<br> # %d - date<br> # %g - Global Diagnostic Context (GDC)<br> # %t - trace<br> # %m - message<br> # %h - thread name<br> # %p - process ID aka PID<br> # %M - formatted message<br> # %l - Level in string form<br> # %x - Nested Diagnostic Context (NDC)<br> # %X - Mapped Diagnostic Context (MDC), syntax is "%X{key}"<br> # %% - Insert a %<br> DirectiveTable = { "c" => 'event.name', "C" => 'event.fullname', "d" => 'format_date', "g" => 'Log4r::GDC.get()', "t" => '(event.tracer.nil? ? "no trace" : event.tracer[0])', "T" => '(event.tracer.nil? ? "no trace" : event.tracer[0].split(File::SEPARATOR)[-1])', "m" => 'event.data', "h" => '(Thread.current[:name] or Thread.current.to_s)', "p" => 'Process.pid.to_s', "M" => 'format_object(event.data)', "l" => 'LNAMES[event.level]', "x" => 'Log4r::NDC.get()', "X" => 'Log4r::MDC.get("DTR_REPLACE")', "%" => '"%"' } # Matches the first directive encountered and the stuff around it. # # * $1 is the stuff before directive or "" if not applicable # * $2 is the directive group or nil if there's none # * $3 is the %#.# match within directive group # * $4 is the .# match which we don't use (it's there to match properly) # * $5 is the directive letter # * $6 is the stuff after the directive or "" if not applicable # * $7 is the remainder DirectiveRegexp = /([^%]*)((%-?\d*(\.\d+)?)([cCdgtTmhpMlxX%]))?(\{.+?\})?(.*)/ # default date format ISO8601 = "%Y-%m-%d %H:%M:%S" attr_reader :pattern, :date_pattern, :date_method # Accepts the following hash arguments (either a string or a symbol): # # [<tt>pattern</tt>] A pattern format string. # [<tt>date_pattern</tt>] A Time#strftime format string. See the # Ruby Time class for details. # [+date_method+] # As an option to date_pattern, specify which # Time.now method to call. For # example, +usec+ or +to_s+. # Specify it as a String or Symbol. # # The default date format is ISO8601, which looks like this: # # yyyy-mm-dd hh:mm:ss => 2001-01-12 13:15:50 def initialize(hash={}) super(hash) @pattern = (hash['pattern'] or hash[:pattern] or nil) @date_pattern = (hash['date_pattern'] or hash[:date_pattern] or nil) @date_method = (hash['date_method'] or hash[:date_method] or nil) @date_pattern = ISO8601 if @date_pattern.nil? and @date_method.nil? PatternFormatter.create_format_methods(self) end # PatternFormatter works by dynamically defining a <tt>format</tt> method # based on the supplied pattern format. This method contains a call to # Kernel#sptrintf with arguments containing the data requested in # the pattern format. # # How is this magic accomplished? First, we visit each directive # and change the %#.# component to %#.#s. The directive letter is then # used to cull an appropriate entry from the DirectiveTable for the # sprintf argument list. After assembling the method definition, we # run module_eval on it, and voila. def PatternFormatter.create_format_methods(pf) #:nodoc: # first, define the format_date method if pf.date_method module_eval "def pf.format_date; Time.now.#{pf.date_method}; end" else module_eval <<-EOS def pf.format_date Time.now.strftime "#{pf.date_pattern}" end EOS end # and now the main format method ebuff = "def pf.format(event)\n sprintf(\"" _pattern = pf.pattern.dup args = [] # the args to sprintf which we'll append to ebuff lastly while true # work on each match in turn match = DirectiveRegexp.match _pattern ebuff << match[1] unless match[1].empty? break if match[2].nil? # deal with the directive by inserting a %#.#s where %#.# is copied # directy from the match ebuff << match[3] + "s" if ( match[5] == 'X' && match[6] != nil ) then # MDC matches, need to be able to handle String, Symbol or Number match6sub = /[\{\}\"]/ mdcmatches = match[6].match /\{(:?)(\d*)(.*)\}/ if ( mdcmatches[1] == "" && mdcmatches[2] == "" ) match6sub = /[\{\}]/ # don't remove surrounding "'s if String end args << DirectiveTable[match[5]].gsub("DTR_REPLACE", match[6]).gsub(match6sub,'') else args << DirectiveTable[match[5]] # cull the data for our argument list end break if match[7].empty? _pattern = match[7] end ebuff << '\n", ' + args.join(', ') + ")\n" ebuff << "end\n" module_eval ebuff end end end