make cython app exit correctly

Azaion.Inference/inference.pyx

@@ -137,7 +137,7 @@ cdef class Inference:
         self._previous_annotation = None
 
         v_input = cv2.VideoCapture(<str>video_name)
-        while v_input.isOpened():
+        while v_input.isOpened() and not self.stop_signal:
             ret, frame = v_input.read()
             if not ret or frame is None:
                 break
@@ -186,11 +186,9 @@ cdef class Inference:
             print(annotation.to_str(self.class_names))
             self.on_annotation(cmd, annotation)
 
-
     cdef stop(self):
         self.stop_signal = True
 
-
     cdef bint is_valid_annotation(self, Annotation annotation):
         # No detections, invalid
         if not annotation.detections:

Azaion.Inference/main.pyx

@@ -1,6 +1,8 @@
+import queue
 import traceback
 from queue import Queue
 cimport constants
+from threading import Thread
 
 from api_client cimport ApiClient
 from annotation cimport Annotation
@@ -20,14 +22,14 @@ cdef class ParsedArguments:
 cdef class CommandProcessor:
     cdef ApiClient api_client
     cdef RemoteCommandHandler remote_handler
-    cdef object command_queue
+    cdef object inference_queue
     cdef bint running
     cdef Inference inference
 
     def __init__(self, args: ParsedArguments):
         self.api_client = ApiClient(args.email, args.password, args.folder)
         self.remote_handler = RemoteCommandHandler(self.on_command)
-        self.command_queue = Queue(maxsize=constants.QUEUE_MAXSIZE)
+        self.inference_queue = Queue(maxsize=constants.QUEUE_MAXSIZE)
         self.remote_handler.start()
         self.running = True
         model = self.api_client.load_ai_model()
@@ -36,11 +38,14 @@ cdef class CommandProcessor:
     def start(self):
         while self.running:
             try:
-                command = self.command_queue.get()
+                command = self.inference_queue.get(timeout=0.5)
                 self.inference.run_inference(command)
                 self.remote_handler.send(command.client_id, <bytes>'DONE'.encode('utf-8'))
+            except queue.Empty:
+                continue
             except Exception as e:
                 traceback.print_exc()
+        print('EXIT!')
 
     cdef on_command(self, RemoteCommand command):
         try:
@@ -50,11 +55,12 @@ cdef class CommandProcessor:
                 response = self.api_client.load_bytes(command.filename)
                 self.remote_handler.send(command.client_id, response)
             elif command.command_type == CommandType.INFERENCE:
-                self.command_queue.put(command)
+                self.inference_queue.put(command)
             elif command.command_type == CommandType.STOP_INFERENCE:
                 self.inference.stop()
             elif command.command_type == CommandType.EXIT:
-                self.stop()
+                t = Thread(target=self.stop) # non-block worker:
+                t.start()
             else:
                 pass
         except Exception as e:
@@ -68,5 +74,6 @@ cdef class CommandProcessor:
         self.remote_handler.send(cmd.client_id, data)
 
     def stop(self):
+        self.inference.stop()
         self.remote_handler.stop()
         self.running = False

Azaion.Inference/remote_command_handler.pxd

@@ -2,6 +2,7 @@ cdef class RemoteCommandHandler:
     cdef object _context
     cdef object _router
     cdef object _dealer
+    cdef object _control
     cdef object _shutdown_event
     cdef object _on_command
 

Azaion.Inference/remote_command_handler.pyx

@@ -9,7 +9,6 @@ cdef class RemoteCommandHandler:
     def __init__(self, object on_command):
         self._on_command = on_command
         self._context = zmq.Context.instance()
-        self._shutdown_event = Event()
 
         self._router = self._context.socket(zmq.ROUTER)
         self._router.setsockopt(zmq.LINGER, 0)
@@ -19,6 +18,10 @@ cdef class RemoteCommandHandler:
         self._dealer.setsockopt(zmq.LINGER, 0)
         self._dealer.bind("inproc://backend")
 
+        self._control = self._context.socket(zmq.PAIR)
+        self._control.bind("inproc://control")
+        self._shutdown_event = Event()
+
         self._proxy_thread = Thread(target=self._proxy_loop, daemon=True)
 
         self._workers = []
@@ -32,7 +35,13 @@ cdef class RemoteCommandHandler:
             worker.start()
 
     cdef _proxy_loop(self):
-        zmq.proxy(self._router, self._dealer)
+        try:
+            zmq.proxy_steerable(self._router, self._dealer, control=self._control)
+        except zmq.error.ZMQError as e:
+            if self._shutdown_event.is_set():
+                print("Shutdown, exit proxy loop.")
+            else:
+                raise
 
     cdef _worker_loop(self):
         worker_socket = self._context.socket(zmq.DEALER)
@@ -40,20 +49,24 @@ cdef class RemoteCommandHandler:
         worker_socket.connect("inproc://backend")
         poller = zmq.Poller()
         poller.register(worker_socket, zmq.POLLIN)
-        print('started receiver loop...')
-        while not self._shutdown_event.is_set():
-            try:
-                socks = dict(poller.poll(500))
-                if worker_socket in socks:
-                    client_id, message = worker_socket.recv_multipart()
-                    cmd = RemoteCommand.from_msgpack(<bytes> message)
-                    cmd.client_id = client_id
-                    print(f'Received [{cmd}] from the client {client_id}')
-                    self._on_command(cmd)
-            except Exception as e:
-                print(f"Worker error: {e}")
-                import traceback
-                traceback.print_exc()
+        try:
+
+            while not self._shutdown_event.is_set():
+                try:
+                    socks = dict(poller.poll(500))
+                    if worker_socket in socks:
+                        client_id, message = worker_socket.recv_multipart()
+                        cmd = RemoteCommand.from_msgpack(<bytes> message)
+                        cmd.client_id = client_id
+                        print(f'Received [{cmd}] from the client {client_id}')
+                        self._on_command(cmd)
+                except Exception as e:
+                    if not self._shutdown_event.is_set():
+                        print(f"Worker error: {e}")
+                        import traceback
+                        traceback.print_exc()
+        finally:
+            worker_socket.close()
 
     cdef send(self, bytes client_id, bytes data):
         with self._context.socket(zmq.DEALER) as socket:
@@ -63,7 +76,16 @@ cdef class RemoteCommandHandler:
 
     cdef stop(self):
         self._shutdown_event.set()
-        time.sleep(0.5)
-        self._router.close()
-        self._dealer.close()
-        self._context.term()
+        try:
+            self._control.send(b"TERMINATE", flags=zmq.DONTWAIT)
+        except zmq.error.ZMQError:
+            pass
+        self._router.close(linger=0)
+        self._dealer.close(linger=0)
+        self._control.close(linger=0)
+
+        self._proxy_thread.join(timeout=2)
+        while any(w.is_alive() for w in self._workers):
+            time.sleep(0.1)
+
+        self._context.term()

Azaion.Inference/token

@@ -1 +1 @@
-eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJuYW1laWQiOiI5N2U5MWI2OC1hNmRlLTQ3YTgtOTgzYi0xOTU3YzViNDQ2MTkiLCJ1bmlxdWVfbmFtZSI6ImFkbWluLXJlbW90ZUBhemFpb24uY29tIiwicm9sZSI6IkFwaUFkbWluIiwibmJmIjoxNzM5MTk5MzM1LCJleHAiOjE3MzkyMTM3MzUsImlhdCI6MTczOTE5OTMzNSwiaXNzIjoiQXphaW9uQXBpIiwiYXVkIjoiQW5ub3RhdG9ycy9PcmFuZ2VQaS9BZG1pbnMifQ.HmfaeFn9T_eJuRZSjBV_EhiSB41ippBVPLRggC7gBZk
+eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJuYW1laWQiOiI5N2U5MWI2OC1hNmRlLTQ3YTgtOTgzYi0xOTU3YzViNDQ2MTkiLCJ1bmlxdWVfbmFtZSI6ImFkbWluLXJlbW90ZUBhemFpb24uY29tIiwicm9sZSI6IkFwaUFkbWluIiwibmJmIjoxNzM5Mjk0ODY2LCJleHAiOjE3MzkzMDkyNjYsImlhdCI6MTczOTI5NDg2NiwiaXNzIjoiQXphaW9uQXBpIiwiYXVkIjoiQW5ub3RhdG9ycy9PcmFuZ2VQaS9BZG1pbnMifQ.fp0YzE42mqtG2fd4BtaX2ZH-0-9YLXHPDqoAHSpfWjk