Add end count to send periodic in BCM

Author: zorce

can/broadcastmanager.py

@@ -104,6 +104,7 @@ def __init__(
         messages: Union[Sequence[Message], Message],
         period: float,
         duration: Optional[float],
+        count: Optional[int],
     ):
         """Message send task with a defined duration and period.
 
@@ -113,9 +114,13 @@ def __init__(
         :param duration:
             Approximate duration in seconds to continue sending messages. If
             no duration is provided, the task will continue indefinitely.
+        :param count:
+            The number of messages to send before stopping. If
+            no count is provided, the task will continue indefinitely.
         """
         super().__init__(messages, period)
         self.duration = duration
+        self.count = count
 
 
 class RestartableCyclicTaskABC(CyclicSendTaskABC):
@@ -207,6 +212,7 @@ def __init__(
         messages: Union[Sequence[Message], Message],
         period: float,
         duration: Optional[float] = None,
+        count: Optional[int] = None,
         on_error: Optional[Callable[[Exception], bool]] = None,
     ):
         """Transmits `messages` with a `period` seconds for `duration` seconds on a `bus`.
@@ -222,12 +228,13 @@ def __init__(
                          it shall return either ``True`` or ``False`` depending
                          on desired behaviour of `ThreadBasedCyclicSendTask`.
         """
-        super().__init__(messages, period, duration)
+        super().__init__(messages, period, duration, count)
         self.bus = bus
         self.send_lock = lock
         self.stopped = True
         self.thread = None
         self.end_time = time.perf_counter() + duration if duration else None
+        self.end_count = count if count else None
         self.on_error = on_error
 
         if HAS_EVENTS:
@@ -257,6 +264,7 @@ def start(self):
 
     def _run(self):
         msg_index = 0
+        count = 0
         while not self.stopped:
             # Prevent calling bus.send from multiple threads
             with self.send_lock:
@@ -272,7 +280,10 @@ def _run(self):
                         break
             if self.end_time is not None and time.perf_counter() >= self.end_time:
                 break
+            if self.end_count is not None and count >= self.end_count:
+                break
             msg_index = (msg_index + 1) % len(self.messages)
+            count += 1
 
             if HAS_EVENTS:
                 win32event.WaitForSingleObject(self.event.handle, self.period_ms)

can/bus.py

@@ -175,6 +175,7 @@ def send_periodic(
         msgs: Union[Sequence[Message], Message],
         period: float,
         duration: Optional[float] = None,
+        count: Optional[int] = None,
         store_task: bool = True,
     ) -> can.broadcastmanager.CyclicSendTaskABC:
         """Start sending messages at a given period on this bus.
@@ -194,6 +195,9 @@ def send_periodic(
         :param duration:
             Approximate duration in seconds to continue sending messages. If
             no duration is provided, the task will continue indefinitely.
+        :param count:
+            The number of messages to send before stopping. If
+            no count is provided, the task will continue indefinitely.
         :param store_task:
             If True (the default) the task will be attached to this Bus instance.
             Disable to instead manage tasks manually.
@@ -222,7 +226,7 @@ def send_periodic(
                 raise ValueError("Must be either a list, tuple, or a Message")
         if not msgs:
             raise ValueError("Must be at least a list or tuple of length 1")
-        task = self._send_periodic_internal(msgs, period, duration)
+        task = self._send_periodic_internal(msgs, period, duration, count)
         # we wrap the task's stop method to also remove it from the Bus's list of tasks
         original_stop_method = task.stop
 
@@ -246,6 +250,7 @@ def _send_periodic_internal(
         msgs: Union[Sequence[Message], Message],
         period: float,
         duration: Optional[float] = None,
+        count: Optional[int] = None,
     ) -> can.broadcastmanager.CyclicSendTaskABC:
         """Default implementation of periodic message sending using threading.
 
@@ -258,6 +263,9 @@ def _send_periodic_internal(
         :param duration:
             The duration between sending each message at the given rate. If
             no duration is provided, the task will continue indefinitely.
+        :param count:
+            The number of messages to send before stopping. If
+            no count is provided, the task will continue indefinitely.
         :return:
             A started task instance. Note the task can be stopped (and
             depending on the backend modified) by calling the :meth:`stop`
@@ -269,7 +277,7 @@ def _send_periodic_internal(
                 threading.Lock()
             )  # pylint: disable=attribute-defined-outside-init
         task = ThreadBasedCyclicSendTask(
-            self, self._lock_send_periodic, msgs, period, duration
+            self, self._lock_send_periodic, msgs, period, duration, count
         )
         return task