119 lines
3.3 KiB
Python
119 lines
3.3 KiB
Python
from threading import Thread
|
|
from queue import Queue
|
|
from os import mkfifo, remove
|
|
from os.path import exists, join
|
|
from signal import signal, SIGTERM, SIGINT
|
|
from secrets import token_urlsafe
|
|
from collections import namedtuple
|
|
from abc import ABC, abstractmethod
|
|
|
|
|
|
class PipeWriterThread(Thread):
|
|
def __init__(self, pipe_path):
|
|
super().__init__()
|
|
self._pipe_path = pipe_path
|
|
self._write_queue = Queue()
|
|
|
|
def write(self, message):
|
|
self._write_queue.put(message, block=True)
|
|
|
|
def run(self):
|
|
while True:
|
|
message = self._write_queue.get(block=True)
|
|
if message is None:
|
|
break
|
|
with open(self._pipe_path, 'wb') as pipe:
|
|
pipe.write(message)
|
|
|
|
def stop(self):
|
|
self._write_queue.put(None)
|
|
self.join()
|
|
|
|
|
|
class PipeReaderThread(Thread):
|
|
_stop_sequence = b'stop_reading'
|
|
|
|
def __init__(self, pipe_path, message_handler):
|
|
super().__init__()
|
|
self._message_handler = message_handler
|
|
self._pipe_path = pipe_path
|
|
|
|
def run(self):
|
|
while True:
|
|
with open(self._pipe_path, 'rb') as pipe:
|
|
message = pipe.read()
|
|
if message == self._stop_sequence:
|
|
break
|
|
self._message_handler(message)
|
|
|
|
def stop(self):
|
|
with open(self._pipe_path, 'wb') as pipe:
|
|
pipe.write(self._stop_sequence)
|
|
self.join()
|
|
|
|
|
|
class PipeHandler:
|
|
def __init__(self, *pipe_paths):
|
|
self._pipe_paths = pipe_paths
|
|
|
|
def recreate(self):
|
|
self.remove()
|
|
for pipe_path in self._pipe_paths:
|
|
mkfifo(pipe_path)
|
|
|
|
def remove(self):
|
|
for pipe_path in self._pipe_paths:
|
|
if exists(pipe_path):
|
|
remove(pipe_path)
|
|
|
|
|
|
class PipeIOServer(ABC):
|
|
def __init__(self, in_pipe=None, out_pipe=None):
|
|
self.in_pipe, self.out_pipe = in_pipe, out_pipe
|
|
self._create_pipes()
|
|
|
|
io_threads_dict = {
|
|
'reader': PipeReaderThread(self.in_pipe, self._handle_message),
|
|
'writer': PipeWriterThread(self.out_pipe)
|
|
}
|
|
IOThreadsTuple = namedtuple('IOThreadsTuple', sorted(io_threads_dict.keys()))
|
|
self._io_threads = IOThreadsTuple(**io_threads_dict)
|
|
|
|
def _create_pipes(self):
|
|
if not self.in_pipe or not self.out_pipe:
|
|
pipe_id = token_urlsafe(6)
|
|
self.in_pipe = join('/tmp', f'in_pipe_{pipe_id}')
|
|
self.out_pipe = join('/tmp', f'out_pipe_{pipe_id}')
|
|
PipeHandler(self.in_pipe, self.out_pipe).recreate()
|
|
|
|
@abstractmethod
|
|
def _handle_message(self, message):
|
|
raise NotImplementedError()
|
|
|
|
def send(self, message):
|
|
self._io_threads.writer.write(message)
|
|
|
|
def run(self):
|
|
for thread in self._io_threads:
|
|
thread.start()
|
|
|
|
def stop(self):
|
|
for thread in self._io_threads:
|
|
thread.stop()
|
|
PipeHandler(self.in_pipe, self.out_pipe).remove()
|
|
|
|
|
|
class EchoPipeIOServer(PipeIOServer):
|
|
def _handle_message(self, message):
|
|
self.send(message)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
pipe_io = EchoPipeIOServer()
|
|
signal(SIGTERM, lambda a, b: pipe_io.stop())
|
|
signal(SIGINT, lambda a, b: pipe_io.stop())
|
|
pipe_io.run()
|
|
print('Running pipe IO server with named pipes:')
|
|
print(f'Input: {pipe_io.in_pipe}')
|
|
print(f'Output: {pipe_io.out_pipe}')
|