Pipes using objects, queues and asyncio

gistfile1.py

import asyncio

class Pipe:
    
    _in_q = None
    _out_q = None
    _chained = False
    
    def __init__(self, *args, **kwargs):        
        self.future = asyncio.async(self.run())
    
    def __or__(self, other):
        self._chained = True
        self._out_q = asyncio.Queue()
        other._in_q = self._out_q
        return other
        
    @asyncio.coroutine
    def get(self):
        item = yield from self._in_q.get()
        return item
            
    @asyncio.coroutine
    def put(self, item):
        if self._chained is True:
            yield from self._out_q.put(item)
    
    @asyncio.coroutine
    def run(self):
        pass


class TextGenerator(Pipe):
    
    @asyncio.coroutine
    def run(self):
        yield from self.put('Hello world!')
        yield from self.put('A pipe example')
        yield from self.put('using asyncio')
        yield from self.put('and some magic functions.')


class Grep(Pipe):
    
    pattern = None
    
    def __init__(self, pattern):
        self.pattern = pattern
        super().__init__()
        
    @asyncio.coroutine
    def run(self):
        while True:
            item = yield from self.get()
            if self.pattern in item:
                yield from self.put(item)


class Printer(Pipe):
     
    @asyncio.coroutine
    def run(self):
        while True:
            item = yield from self.get()
            print (item)
                

TextGenerator() | Grep('a') | Grep('e') | Grep('i') | Grep('o') | Grep('u') | Printer()

asyncio.get_event_loop().run_forever()