class File::Tail::Group
This class can be used to coordinate tailing of many files, which have been added to the group.
Public Class Methods
Creates a group for files
(IO instances or filename strings).
# File lib/file/tail/group.rb, line 21 def self.[](*files) new(:files => files) end
Creates a new File::Tail::Group instance.
The following options can be given as arguments:
- :files
-
an array of files (or filenames to open) that are placed into the group.
# File lib/file/tail/group.rb, line 13 def initialize(opts = {}) @tailers = ThreadGroup.new if files = opts[:files] Array(files).each { |file| add file } end end
Public Instance Methods
Add a file (IO instance) or filename (responding to to_str) to this group.
# File lib/file/tail/group.rb, line 27 def add(file_or_filename) if file_or_filename.respond_to?(:to_io) add_file file_or_filename.to_io elsif file_or_filename.respond_to?(:to_str) add_filename file_or_filename end end
Add the IO instance file
to this group.
# File lib/file/tail/group.rb, line 38 def add_file(file) setup_file_tailer file self end
Add a file created by opening filename
to this group after
stepping n
lines backwards from the end of it.
# File lib/file/tail/group.rb, line 45 def add_filename(filename, n = 0) file = Logfile.open(filename.to_str, :backward => n) file.backward n setup_file_tailer file self end
Iterate over all files contained in this group yielding to
block
for each of them.
# File lib/file/tail/group.rb, line 54 def each_file(&block) each_tailer { |t| t.file }.map(&block) end
Iterate over all tailers in this group yielding to block
for
each of them.
# File lib/file/tail/group.rb, line 60 def each_tailer(&block) @tailers.list.map(&block) end
Stop all tailers in this group at once.
# File lib/file/tail/group.rb, line 65 def stop each_tailer { |t| t.stop } each_tailer { |t| t.join } self end
Tail all the lines of all the files in the Tail::Group instance, that is yield to each of them.
Every line is extended with the LineExtension module, that adds some methods to the line string. To get the path of the file this line was received from call line.file.path.
# File lib/file/tail/group.rb, line 77 def tail wait_for_activity do |tailer| tailer.pending_lines.each do |line| line.extend LineExtension line.instance_variable_set :@tailer, tailer yield line end end end
Private Instance Methods
# File lib/file/tail/group.rb, line 89 def setup_file_tailer(file) file.extend File::Tail setup = ConditionVariable.new mutex = Mutex.new ft = nil mutex.synchronize do ft = Tailer.new do t = Thread.current t[:queue] = Queue.new t[:file] = file mutex.synchronize do setup.signal end file.tail { |line| t[:queue] << line } end setup.wait mutex end @tailers.add ft nil end
Wait until new input is receŃ–ved on any of the tailers in the group. If so
call block
with all of these trailers as an argument.
# File lib/file/tail/group.rb, line 112 def wait_for_activity(&block) loop do pending = each_tailer.select(&:pending_lines?) if pending.empty? interval = each_file.map { |t| t.interval }.compact.min || 0.1 sleep interval else pending.each(&block) end end end