avail.rb

#!/usr/bin/env ruby

require 'osx/cocoa'
require 'optparse'
include OSX

$service_name = nil
$service_port = nil
$service_type = nil

$service_txt = {}

target_plist_file = nil
$avail_debug = false
def log(s)
	$stderr.puts s if $avail_debug
end

OptionParser.new do |o|
	o.on('-s', '--service TYPE', 'The Bonjour service type to publish.') do |name|
		$service_type = name
	end
	
	o.on('-n', '--name NAME', 'The name of the service. If unspecified, uses hostname') do |name|
		$service_name = name
	end
	
	o.on('-p', '--port NAME', 'The port to publish.') do |port|
		$service_port = port.to_i
	end
	
	o.on('-t', '--txt VAL', 'The value to add to the service data dictionary. VAL is of the form "key=value". Strings will be encoded as UTF-8.') do |val|
		
		split = val.split('=')
		key = split[0]
		split.delete_at 0
		value = split.join('=')
		
		$service_txt[key] = value
		
	end
	
	o.on('-P', '--launchd-plist FILE', 'If specified, does not run. Instead, produces a launchd plist file that runs this copy of $0 with the same parameters you passed in.') do |file|
		target_plist_file = file
	end
	
	o.on('-D', '--debug', 'Shows debug output.') do
		$avail_debug = true
	end
	
	o.on('--http PATH', 'Shorthand that registers a HTTP service on the given port. You can still provide a name with -n and a port with -p.') do |path|
		$service_type = '_http._tcp.'
		$service_txt['path'] = path
	end
	
end.parse!

raise "You must specify both service type and port!" unless $service_type and $service_port

if target_plist_file
	
	label = File.basename(target_plist_file, '.plist')
	
	args = [
		File.expand_path(__FILE__),
		'-s', $service_type,
		'-p', $service_port.to_s
	]
	
	if $service_name
		args << '-n'
		args << $service_name
	end
	
	$service_txt.each do |key, value|
		args << '-t'
		args << "#{key}=#{value}"
	end
	
	if $avail_debug
		args << '--debug'
	end
	
	plist = {
		'Label' => label,
		'ProgramArguments' => args,
		'KeepAlive' => true,
		'RunAtLoad' => true,
	}
	
	saved = NSDictionary.dictionaryWithDictionary(plist).writeToFile_atomically(target_plist_file, true)
	
	if saved
		exit 1
	else
		exit 0
	end
end

unless $service_name
	$service_name = NSHost.currentHost.name
end

class Publisher < NSObject
	def initialize()
		@running = true
		@services = {}
		@domains = []
		
		@browser = NSNetServiceBrowser.alloc.init
		@browser.setDelegate self
		@browser.searchForRegistrationDomains
		log "Will start looking for domains."
	end
	
	def netServiceBrowser_didFindDomain_moreComing(browser, domain, coming)
		log "Domain found: #{domain}"
		return if @domains.include? domain
		domain = domain.to_s
		
		@domains << domain
		s = NSNetService.alloc.initWithDomain_type_name_port_(domain, $service_type, $service_name, $service_port)
		s.TXTRecordData = NSNetService.dataFromTXTRecordDictionary($service_txt)
		log "Created service: #{s}"
		s.setDelegate self
		@services[domain.to_s] = s
		log "Services now: #{@services.inspect}"
		s.publish
	end
	
	def netServiceBrowser_didRemoveDomain_moreComing(browser, domain, coming)
		domain = domain.to_s
		
		@domains.delete domain
		@services[domain].setDelegate nil
		@services[domain].stop
		@services.delete domain
	end
	
	def netServiceWillPublish(service)
		log "About to publish service: #{service}"
	end
	
	def netServiceDidPublish(service)
		log "Did publish service: #{service}"
	end
	
	def netService_didNotPublish(service, error)
		log "Did not publish #{service}, because: #{error}"
		@services[service.domain.to_s] = nil
	end
	
	def running
		@running
	end
	
	def stop_asap
		@running = false
	end
	
	def stop
		@services.each do |domain, service|
			service.setDelegate nil
			service.stop
		end
		@services = nil
		@domains = nil
		@browser.stop
		@browser.setDelegate nil
		@browser = nil
	end
end

publisher = Publisher.new
trap "SIGTERM" do
	publisher.stop_asap
end

while publisher.running
	begin
		NSRunLoop.currentRunLoop.runUntilDate NSDate.dateWithTimeIntervalSinceNow(2)
	rescue Interrupt
		publisher.stop_asap
	end
end

publisher.stop