# File lib/fluent/plugin/in_tail.rb, line 21 def initialize super @paths = [] @tails = {} end
Fluent::NewTailInput::TailWatcher#close is called by another thread at shutdown phase. It causes 'can't modify string; temporarily locked' error in IOHandler so adding close_io argument to avoid this problem. At shutdown, IOHandler's io will be released automatically after detached the event loop
# File lib/fluent/plugin/in_tail.rb, line 179 def close_watcher(tw, close_io = true) tw.close(close_io) flush_buffer(tw) if tw.unwatched && @pf @pf[tw.path].update_pos(PositionFile::UNWATCHED_POSITION) end end
# File lib/fluent/plugin/in_tail.rb, line 187 def close_watcher_after_rotate_wait(tw) closer = TailWatcher::Closer.new(@rotate_wait, tw, log, &method(:close_watcher)) closer.attach(@loop) end
# File lib/fluent/plugin/in_tail.rb, line 36 def configure(conf) super @paths = @path.split(',').map {|path| path.strip } if @paths.empty? raise ConfigError, "tail: 'path' parameter is required on tail input" end unless @pos_file $log.warn "'pos_file PATH' parameter is not set to a 'tail' source." $log.warn "this parameter is highly recommended to save the position to resume tailing." end configure_parser(conf) configure_tag @multiline_mode = conf['format'] =~ /multiline/ @receive_handler = if @multiline_mode method(:parse_multilines) else method(:parse_singleline) end end
# File lib/fluent/plugin/in_tail.rb, line 60 def configure_parser(conf) @parser = Plugin.new_parser(conf['format']) @parser.configure(conf) end
# File lib/fluent/plugin/in_tail.rb, line 65 def configure_tag if @tag.index('*') @tag_prefix, @tag_suffix = @tag.split('*') @tag_suffix ||= '' else @tag_prefix = nil @tag_suffix = nil end end
# File lib/fluent/plugin/in_tail.rb, line 233 def convert_line_to_event(line, es) begin line.chomp! # remove \n @parser.parse(line) { |time, record| if time && record es.add(time, record) else log.warn "pattern not match: #{line.inspect}" end } rescue => e log.warn line.dump, :error => e.to_s log.debug_backtrace(e.backtrace) end end
# File lib/fluent/plugin/in_tail.rb, line 99 def expand_paths date = Time.now paths = [] @paths.each { |path| path = date.strftime(path) if path.include?('*') paths += Dir.glob(path) else # When file is not created yet, Dir.glob returns an empty array. So just add when path is static. paths << path end } paths end
# File lib/fluent/plugin/in_tail.rb, line 192 def flush_buffer(tw) if lb = tw.line_buffer lb.chomp! @parser.parse(lb) { |time, record| if time && record tag = if @tag_prefix || @tag_suffix @tag_prefix + tw.tag + @tag_suffix else @tag end router.emit(tag, time, record) else log.warn "got incomplete line at shutdown from #{tw.path}: #{lb.inspect}" end } end end
# File lib/fluent/plugin/in_tail.rb, line 257 def parse_multilines(lines, tail_watcher) lb = tail_watcher.line_buffer es = MultiEventStream.new if @parser.has_firstline? lines.each { |line| if @parser.firstline?(line) if lb convert_line_to_event(lb, es) end lb = line else if lb.nil? log.warn "got incomplete line before first line from #{tail_watcher.path}: #{line.inspect}" else lb << line end end } else lb ||= '' lines.each do |line| lb << line @parser.parse(lb) { |time, record| if time && record convert_line_to_event(lb, es) lb = '' end } end end tail_watcher.line_buffer = lb es end
# File lib/fluent/plugin/in_tail.rb, line 249 def parse_singleline(lines, tail_watcher) es = MultiEventStream.new lines.each { |line| convert_line_to_event(line, es) } es end
# File lib/fluent/plugin/in_tail.rb, line 217 def receive_lines(lines, tail_watcher) es = @receive_handler.call(lines, tail_watcher) unless es.empty? tag = if @tag_prefix || @tag_suffix @tag_prefix + tail_watcher.tag + @tag_suffix else @tag end begin router.emit_stream(tag, es) rescue # ignore errors. Engine shows logs and backtraces. end end end
in_tail with '*' path doesn't check rotation file equality at refresh phase. So you should not use '*' path when your logs will be rotated by another tool. It will cause log duplication after updated watch files. In such case, you should separate log directory and specify two paths in path parameter. e.g. path /path/to/dir/*,/path/to/rotated_logs/target_file
# File lib/fluent/plugin/in_tail.rb, line 119 def refresh_watchers target_paths = expand_paths existence_paths = @tails.keys unwatched = existence_paths - target_paths added = target_paths - existence_paths stop_watchers(unwatched, false, true) unless unwatched.empty? start_watchers(added) unless added.empty? end
# File lib/fluent/plugin/in_tail.rb, line 210 def run @loop.run rescue log.error "unexpected error", :error=>$!.to_s log.error_backtrace end
# File lib/fluent/plugin/in_tail.rb, line 130 def setup_watcher(path, pe) tw = TailWatcher.new(path, @rotate_wait, pe, log, @read_from_head, method(:update_watcher), &method(:receive_lines)) tw.attach(@loop) tw end
# File lib/fluent/plugin/in_tail.rb, line 90 def shutdown @refresh_trigger.detach if @refresh_trigger && @refresh_trigger.attached? stop_watchers(@tails.keys, true) @loop.stop rescue nil # when all watchers are detached, `stop` raises RuntimeError. We can ignore this exception. @thread.join @pf_file.close if @pf_file end
# File lib/fluent/plugin/in_tail.rb, line 75 def start if @pos_file @pf_file = File.open(@pos_file, File::RDWR|File::CREAT, DEFAULT_FILE_PERMISSION) @pf_file.sync = true @pf = PositionFile.parse(@pf_file) end @loop = Coolio::Loop.new refresh_watchers @refresh_trigger = TailWatcher::TimerWatcher.new(@refresh_interval, true, log, &method(:refresh_watchers)) @refresh_trigger.attach(@loop) @thread = Thread.new(&method(:run)) end
# File lib/fluent/plugin/in_tail.rb, line 136 def start_watchers(paths) paths.each { |path| pe = nil if @pf pe = @pf[path] if @read_from_head && pe.read_inode.zero? begin pe.update(File::Stat.new(path).ino, 0) rescue Errno::ENOENT $log.warn "#{path} not found. Continuing without tailing it." end end end @tails[path] = setup_watcher(path, pe) } end
# File lib/fluent/plugin/in_tail.rb, line 154 def stop_watchers(paths, immediate = false, unwatched = false) paths.each { |path| tw = @tails.delete(path) if tw tw.unwatched = unwatched if immediate close_watcher(tw, false) else close_watcher_after_rotate_wait(tw) end end } end
#refresh_watchers calls @tails.keys so we don't use stop_watcher -> start_watcher sequence for safety.
# File lib/fluent/plugin/in_tail.rb, line 169 def update_watcher(path, pe) rotated_tw = @tails[path] @tails[path] = setup_watcher(path, pe) close_watcher_after_rotate_wait(rotated_tw) if rotated_tw end