Make PipeIOServer usable as a base class

pipe_io_server.py

@@ -5,6 +5,7 @@ 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):
@@ -66,7 +67,7 @@ class PipeHandler:
                 remove(pipe_path)
 
 
-class PipeIOServer:
+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()
@@ -85,7 +86,11 @@ class PipeIOServer:
             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):
@@ -98,8 +103,13 @@ class PipeIOServer:
         PipeHandler(self.in_pipe, self.out_pipe).remove()
 
 
+class EchoPipeIOServer(PipeIOServer):
+    def _handle_message(self, message):
+        self.send(message)
+
+
 if __name__ == "__main__":
-    pipe_io = PipeIOServer()
+    pipe_io = EchoPipeIOServer()
     signal(SIGTERM, lambda a, b: pipe_io.stop())
     signal(SIGINT, lambda a, b: pipe_io.stop())
     pipe_io.run()