Module: EventMachine

Defined in:
lib/em/globwatcher.rb,
lib/em/filetail.rb

Overview

Add EventMachine::file_tail

Defined Under Namespace

Classes: FileTail

Class Method Summary collapse

Class Method Details

.file_tail(path, handler = nil, *args, &block) ⇒ Object

Tail a file.

path is the path to the file to tail. handler should be a module implementing ‘receive_data’ or must be a subclasses of EventMachine::FileTail

For example:

EM::file_tail("/var/log/messages", MyHandler)

If a block is given, and the handler is not specified or does not implement EventMachine::FileTail#receive_data, then it will be called as such:

EM::file_tail(...) do |filetail, line|
  # filetail is the FileTail instance watching the file
  # line is the line read from the file
end



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# File 'lib/em/filetail.rb', line 463

def self.file_tail(path, handler=nil, *args, &block)
  # This code mostly styled on what EventMachine does in many of it's other
  # methods.
  args = [path, *args]
  klass = klass_from_handler(EventMachine::FileTail, handler, *args);
  c = klass.new(*args, &block)
  return c
end

.glob_tail(glob, handler = nil, *args, &block) ⇒ Object

Watch a glob and tail any files found.

  • glob - a string path or glob, such as /var/log/*.log

  • handler - a module or subclass of EventMachine::FileGlobWatchTail. handler can be omitted if you give a block.

If you give a block and omit the handler parameter, then the behavior is that your block is called for every line read from any file the same way EventMachine::file_tail does when called with a block.

See EventMachine::FileGlobWatchTail for the callback methods.
See EventMachine::file_tail for more information about block behavior.



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# File 'lib/em/globwatcher.rb', line 264

def self.glob_tail(glob, handler=nil, *args, &block)
  handler = EventMachine::FileGlobWatchTail if handler == nil
  args.unshift(glob)
  klass = klass_from_handler(EventMachine::FileGlobWatchTail, handler, *args)
  c = klass.new(*args, &block)
  return c
end

.watch_glob(glob, handler = nil, *args) {|c| ... } ⇒ Object

Watch a glob for any files.

  • glob - a string path or glob, such as “/var/log/*.log”

  • handler - must be a module or a subclass of EventMachine::FileGlobWatch

The remaining (optional) arguments are passed to your handler like this:

If you call this:
  EventMachine.watch_glob("/var/log/*.log", YourHandler, 1, 2, 3, ...)
This will be invoked when new matching files are found:
  YourHandler.new(path_found, 1, 2, 3, ...)
  ^ path_found is the new path found by the glob

See EventMachine::FileGlobWatch for the callback methods.

Yields:

  • (c) 


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# File 'lib/em/globwatcher.rb', line 285

def self.watch_glob(glob, handler=nil, *args)
  # This code mostly styled on what EventMachine does in many of it's other
  # methods.
  args = [glob, *args]
  klass = klass_from_handler(EventMachine::FileGlobWatch, handler, *args);
  c = klass.new(*args)
  yield c if block_given?
  return c
end