Removing `match` statement with `if-else` as many people still uses <python 3.10 😭

examples/python-dataflow/object_detection.py

@@ -13,23 +13,23 @@ model = torch.hub.load("ultralytics/yolov5", "yolov5n")
 node = Node()
 
 for event in node:
-    match event["type"]:
-        case "INPUT":
-            match event["id"]:
-                case "image":
-                    print("[object detection] received image input")
-                    frame = event["value"].to_numpy()
-                    frame = cv2.imdecode(frame, -1)
-                    frame = frame[:, :, ::-1]  # OpenCV image (BGR to RGB)
-                    results = model(frame)  # includes NMS
-                    arrays = np.array(results.xyxy[0].cpu()).tobytes()
+    event_type = event["type"]
+    if event_type == "INPUT":
+        event_id = event["id"]
+        if event_id == "image":
+            print("[object detection] received image input")
+            frame = event["value"].to_numpy()
+            frame = cv2.imdecode(frame, -1)
+            frame = frame[:, :, ::-1]  # OpenCV image (BGR to RGB)
+            results = model(frame)  # includes NMS
+            arrays = np.array(results.xyxy[0].cpu()).tobytes()
 
-                    node.send_output("bbox", arrays, event["metadata"])
-                case other:
-                    print("[object detection] ignoring unexpected input:", other)
-        case "STOP":
-            print("[object detection] received stop")
-        case "ERROR":
-            print("[object detection] error: ", event["error"])
-        case other:
-            print("[object detection] received unexpected event:", other)
+            node.send_output("bbox", arrays, event["metadata"])
+        else:
+            print("[object detection] ignoring unexpected input:", event_id)
+    elif event_type == "INPUT":
+        print("[object detection] received stop")
+    elif event_type == "ERROR":
+        print("[object detection] error: ", event["error"])
+    else:
+        print("[object detection] received unexpected event:", event_type)

examples/python-dataflow/plot.py

@@ -83,16 +83,16 @@ plotter = Plotter()
 node = Node()
 
 for event in node:
-    match event["type"]:
-        case "INPUT":
-            status = plotter.on_input(event)
-            match status:
-                case DoraStatus.CONTINUE:
-                    pass
-                case DoraStatus.STOP:
-                    print("plotter returned stop status")
-                    break
-        case "STOP":
-            print("received stop")
-        case other:
-            print("received unexpected event:", other)
+    event_type = event["type"]
+    if event_type == "INPUT":
+        status = plotter.on_input(event)
+        match status:
+            case DoraStatus.CONTINUE:
+                pass
+            case DoraStatus.STOP:
+                print("plotter returned stop status")
+                break
+    elif event_type == "INPUT":
+        print("received stop")
+    else:
+        print("received unexpected event:", event_type)

examples/python-dataflow/webcam.py

@@ -22,31 +22,31 @@ start = time.time()
 while time.time() - start < 10:
     # Wait next dora_input
     event = node.next()
-    match event["type"]:
-        case "INPUT":
-            ret, frame = video_capture.read()
-            if not ret:
-                frame = np.zeros((CAMERA_HEIGHT, CAMERA_WIDTH, 3), dtype=np.uint8)
-                cv2.putText(
-                    frame,
-                    "No Webcam was found at index %d" % (CAMERA_INDEX),
-                    (int(30), int(30)),
-                    font,
-                    0.75,
-                    (255, 255, 255),
-                    2,
-                    1,
-                )
-            node.send_output(
-                "image",
-                cv2.imencode(".jpg", frame)[1].tobytes(),
-                event["metadata"],
+    event_type = event["type"]
+    if event_type == "INPUT":
+        ret, frame = video_capture.read()
+        if not ret:
+            frame = np.zeros((CAMERA_HEIGHT, CAMERA_WIDTH, 3), dtype=np.uint8)
+            cv2.putText(
+                frame,
+                "No Webcam was found at index %d" % (CAMERA_INDEX),
+                (int(30), int(30)),
+                font,
+                0.75,
+                (255, 255, 255),
+                2,
+                1,
             )
-        case "STOP":
-            print("received stop")
-            break
-        case other:
-            print("received unexpected event:", other)
-            break
+        node.send_output(
+            "image",
+            cv2.imencode(".jpg", frame)[1].tobytes(),
+            event["metadata"],
+        )
+    elif event_type == "INPUT":
+        print("received stop")
+        break
+    else:
+        print("received unexpected event:", event_type)
+        break
 
 video_capture.release()

examples/python-operator-dataflow/webcam.py

@@ -33,35 +33,35 @@ class Operator:
         dora_event: str,
         send_output,
     ) -> DoraStatus:
-        match dora_event["type"]:
-            case "INPUT":
-                ret, frame = self.video_capture.read()
-                if ret:
-                    frame = cv2.resize(frame, (CAMERA_WIDTH, CAMERA_HEIGHT))
+        event_type = dora_event["type"]
+        if event_type == "INPUT":
+            ret, frame = self.video_capture.read()
+            if ret:
+                frame = cv2.resize(frame, (CAMERA_WIDTH, CAMERA_HEIGHT))
 
-                ## Push an error image in case the camera is not available.
-                else:
-                    frame = np.zeros((CAMERA_HEIGHT, CAMERA_WIDTH, 3), dtype=np.uint8)
-                    cv2.putText(
-                        frame,
-                        "No Webcam was found at index %d" % (CAMERA_INDEX),
-                        (int(30), int(30)),
-                        font,
-                        0.75,
-                        (255, 255, 255),
-                        2,
-                        1,
-                    )
-
-                send_output(
-                    "image",
-                    pa.array(frame.ravel()),
-                    dora_event["metadata"],
+            ## Push an error image in case the camera is not available.
+            else:
+                frame = np.zeros((CAMERA_HEIGHT, CAMERA_WIDTH, 3), dtype=np.uint8)
+                cv2.putText(
+                    frame,
+                    "No Webcam was found at index %d" % (CAMERA_INDEX),
+                    (int(30), int(30)),
+                    font,
+                    0.75,
+                    (255, 255, 255),
+                    2,
+                    1,
                 )
-            case "STOP":
-                print("received stop")
-            case other:
-                print("received unexpected event:", other)
+
+            send_output(
+                "image",
+                pa.array(frame.ravel()),
+                dora_event["metadata"],
+            )
+        elif event_type == "INPUT":
+            print("received stop")
+        else:
+            print("received unexpected event:", event_type)
 
         if time.time() - self.start_time < 20:
             return DoraStatus.CONTINUE

examples/python-ros2-dataflow/control_node.py

@@ -12,22 +12,22 @@ for i in range(500):
     if event is None:
         break
     if event["type"] == "INPUT":
-        match event["id"]:
-            case "turtle_pose":
-                print(
-                    f"""Pose: {event["value"].tolist()}""".replace("\r", "").replace(
-                        "\n", " "
-                    )
+        event_id = event["id"]
+        if event_id == "turtle_pose":
+            print(
+                f"""Pose: {event["value"].tolist()}""".replace("\r", "").replace(
+                    "\n", " "
                 )
-            case "tick":
-                direction = {
-                    "linear": {
-                        "x": 1.0 + random.random(),
-                    },
-                    "angular": {"z": (random.random() - 0.5) * 5},
-                }
+            )
+        elif event_id == "tick":
+            direction = {
+                "linear": {
+                    "x": 1.0 + random.random(),
+                },
+                "angular": {"z": (random.random() - 0.5) * 5},
+            }
 
-                node.send_output(
-                    "direction",
-                    pa.array([direction]),
-                )
+            node.send_output(
+                "direction",
+                pa.array([direction]),
+            )

examples/python-ros2-dataflow/random_turtle.py

@@ -43,20 +43,20 @@ for i in range(500):
     event = dora_node.next()
     if event is None:
         break
-    match event["kind"]:
-        # Dora event
-        case "dora":
-            match event["type"]:
-                case "INPUT":
-                    match event["id"]:
-                        case "direction":
-                            twist_writer.publish(event["value"])
+    event_kind = event["kind"]
+    # Dora event
+    if event_kind == "dora":
+        event_type = event["type"]
+        if event_type == "INPUT":
+            event_id = event["id"]
+            if event_id == "direction":
+                twist_writer.publish(event["value"])
 
         # ROS2 Event
-        case "external":
-            pose = event.inner()[0].as_py()
-            if i == CHECK_TICK:
-                assert (
-                    pose["x"] != 5.544444561004639
-                ), "turtle should not be at initial x axis"
-            dora_node.send_output("turtle_pose", event.inner())
+    elif event_kind == "external":
+        pose = event.inner()[0].as_py()
+        if i == CHECK_TICK:
+            assert (
+                pose["x"] != 5.544444561004639
+            ), "turtle should not be at initial x axis"
+        dora_node.send_output("turtle_pose", event.inner())