class Rucola::FSEvents

Attributes

allocator[RW]
context[RW]
flags[RW]
latency[RW]
paths[R]
since[RW]
stream[R]

Public Class Methods

new(*params, &block) click to toggle source

Creates a new FSEvents `watchdog` object. You can specify a list of paths to watch and options to control the behaviour of the watchdog. The block you pass serves as a callback when an event is generated on one of the specified paths.

fsevents = FSEvents.new('/etc/passwd') { Mailer.send_mail("Someone touched the password file!") }
fsevents.create_stream
fsevents.start

fsevents = FSEvents.new('/home/upload', :since => UploadWatcher.last_event_id) do |events|
  events.each do |event|
    UploadWatcher.last_event_id = event.id
    event.files.each do |file|
      UploadWatcher.logfile.append("#{file} was changed")
    end
  end
end

*:since: The service will report events that have happened after the supplied event ID. Never use 0 because that

will cause every fsevent since the "beginning of time" to be reported. Use OSX::KFSEventStreamEventIdSinceNow
if you want to receive events that have happened after this call. (Default: OSX::KFSEventStreamEventIdSinceNow).
You can find the ID's passed with :since in the events passed to your block.

*:latency: Number of seconds to wait until an FSEvent is reported, this allows the service to bundle events. (Default: 0.0)

Please refer to the Cocoa documentation for the rest of the options.

# File lib/fssm/backends/rubycocoa/fsevents.rb, line 87
def initialize(*params, &block)
  raise ArgumentError, 'No callback block was specified.' unless block_given?

  options = params.last.kind_of?(Hash) ? params.pop : {}
  @paths  = params.flatten

  paths.each { |path| raise ArgumentError, "The specified path (#{path}) does not exist." unless File.exist?(path) }

  @allocator     = options[:allocator] || OSX::KCFAllocatorDefault
  @context       = options[:context] || nil
  @since         = options[:since] || OSX::KFSEventStreamEventIdSinceNow
  @latency       = options[:latency] || 0.0
  @flags         = options[:flags] || 0
  @stream        = options[:stream] || nil

  @user_callback = block
  @callback      = Proc.new do |stream, client_callback_info, number_of_events, paths_pointer, event_flags, event_ids|
    paths_pointer.regard_as('*')
    events = []
    number_of_events.times { |i| events << Rucola::FSEvents::FSEvent.new(self, event_ids[i], paths_pointer[i]) }
    @user_callback.call(events)
  end
end
start_watching(*params, &block) click to toggle source

Initializes a new FSEvents `watchdog` object and starts watching the directories you specify for events. The block is used as a handler for events, which are passed as the block's argument. This method is the easiest way to start watching some directories if you don't care about the details of setting up the event stream.

Rucola::FSEvents.start_watching('/tmp') do |events|
  events.each { |event| log.debug("#{event.files.inspect} were changed.") }
end

Rucola::FSEvents.start_watching('/var/log/system.log', '/var/log/secure.log', :since => last_id, :latency => 5) do
  Growl.notify("Something was added to your log files!")
end

Note that the method also returns the FSEvents object. This enables you to control the event stream if you want to.

fsevents = Rucola::FSEvents.start_watching('/Volumes') do |events|
  events.each { |event| Growl.notify("Volume changes: #{event.files.to_sentence}") }
end
fsevents.stop
# File lib/fssm/backends/rubycocoa/fsevents.rb, line 56
def self.start_watching(*params, &block)
  fsevents = new(*params, &block)
  fsevents.create_stream
  fsevents.start
  fsevents
end

Public Instance Methods

create_stream() click to toggle source

Create the stream. Raises a Rucola::FSEvents::StreamError if the stream could not be created.

# File lib/fssm/backends/rubycocoa/fsevents.rb, line 113
def create_stream
  @stream = OSX.FSEventStreamCreate(@allocator, @callback, @context, @paths, @since, @latency, @flags)
  raise(StreamError, 'Unable to create FSEvents stream.') unless @stream
  OSX.FSEventStreamScheduleWithRunLoop(@stream, OSX.CFRunLoopGetCurrent, OSX::KCFRunLoopDefaultMode)
end
start() click to toggle source

Start the stream. Raises a Rucola::FSEvents::StreamError if the stream could not be started.

# File lib/fssm/backends/rubycocoa/fsevents.rb, line 121
def start
  raise(StreamError, 'Unable to start FSEvents stream.') unless OSX.FSEventStreamStart(@stream)
end
stop() click to toggle source

Stop the stream. You can resume it by calling `start` again.

# File lib/fssm/backends/rubycocoa/fsevents.rb, line 127
def stop
  OSX.FSEventStreamStop(@stream)
end