Code for Factory Method

client_code.py

if __name__ == '__main__':
	domain = 'ftp.freebsd.org'
	path = '/pub/FreeBSD/'
	protocol = input('Connecting to {}. Which Protocol to use? (0-http,1-ftp): '.format(domain))

	if protocol == 0:
		is_secure = bool(input('Use secure connection? (1-yes, 0-no): '))
		connector = HTTPConnector(is_secure)
	else:
		is_secure = False
		connector = FTPConnector(is_secure)

	try:
		content = connector.read(domain, path)
	except urllib2.URLError, e:
		print 'Can not access resource with this method'
	else:
		print connector.parse(content)

connectors.py

class HTTPConnector(Connector):
     """A concrete creator that creates a HTTP connector and sets in
   runtime all its attributes."""
     
     def protocol_factory_method(self):
       if self.is_secure:
         return 'https'
       return 'http'

     def port_factory_method(self):
       """Here HTTPPort and HTTPSecurePort are concrete objects, created by factory method."""
       if self.is_secure:
         return HTTPSecurePort()
       return HTTPPort()
     
     def parse(self, content):
       """Parses web content."""
       filenames = []
       soup = BeautifulStoneSoup(content)
       links = soup.table.findAll('a')
       for link in links:
         filenames.append(link['href'])
       return '\n'.join(filenames)

class FTPConnector(Connector):
	"""A concrete creator that creates a FTP connector and sets in
	runtime all its attributes."""
	def protocol_factory_method(self):
		return 'ftp'

	def port_factory_method(self):
		return FTPPort()

	def parse(self, content):
		lines = content.split('\n')
		filenames = []
		
		for line in lines:
		# The FTP format typically has 8 columns
			splitted_line = line.split(None, 8)
			if len(splitted_line) == 9:
				filenames.append(splitted_line[-1])
		return '\n'.join(filenames)

methods.py

@abc.abstractmethod
def parse(self):
	"""Parses web content.
	This method should be redefined in the runtime."""
	pass

products.py

class Port(object):
	__metaclass__ = abc.ABCMeta
	"""Abstract product. One of its subclasses will be created in factory methods."""
	
	@abc.abstractmethod
	def __str__(self):
		pass