Merge pull request #16 from SimLeek/exceptions

Exceptions

cvpubsubs/__init__.py

@@ -1 +1 @@
-__version__ = '0.5.0'
+__version__ = '0.6.0'

cvpubsubs/callbacks.py

@@ -31,8 +31,8 @@ class function_display_callback(object):  # NOSONAR
         ...     array[coords[0:2]] = (array[coords[0:2]] + [r,g,b])%1.0
         >>> VideoHandlerThread(video_source=img, callbacks=function_display_callback(fun)).display()
 
-        :param display_function:
-        :param finish_function:
+        :param display_function: a function to run on the input image.
+        :param finish_function: a function to run on the input image when the other function finishes.
         """
         self.looping = True
         self.first_call = True

cvpubsubs/webcam_pub/frame_handler.py

@@ -4,13 +4,15 @@ import numpy as np
 
 from cvpubsubs.webcam_pub.pub_cam import pub_cam_thread
 from cvpubsubs.webcam_pub.camctrl import CamCtrl
+from cvpubsubs.window_sub.winctrl import WinCtrl
+
 
 if False:
     from typing import Union, Tuple, Any, Callable, List, Optional
 
     FrameCallable = Callable[[np.ndarray, int], Optional[np.ndarray]]
 
-from cvpubsubs.webcam_pub.callbacks import global_cv_display_callback
+from cvpubsubs.callbacks import global_cv_display_callback
 
 display_callbacks = [global_cv_display_callback]
 
@@ -53,6 +55,7 @@ class VideoHandlerThread(threading.Thread):
         self.request_size = request_size
         self.high_speed = high_speed
         self.fps_limit = fps_limit
+        self.exception_raised = None
 
     def loop(self):
         """Continually gets frames from the video publisher, runs callbacks on them, and listens to commands."""
@@ -66,7 +69,14 @@ class VideoHandlerThread(threading.Thread):
             frame = sub_cam.get(blocking=True, timeout=1.0)  # type: np.ndarray
             if frame is not None:
                 for c in self.callbacks:
-                    frame_c = c(frame, self.cam_id)
+                    try:
+                        frame_c = c(frame, self.cam_id)
+                    except Exception as e:
+                        import traceback
+                        CamCtrl.stop_cam(self.cam_id)
+                        WinCtrl.quit()
+                        self.exception_raised = e
+                        frame_c = self.exception_raised
                     if frame_c is not None:
                         frame = frame_c
             msg_owner = sub_owner.get()
@@ -93,3 +103,5 @@ class VideoHandlerThread(threading.Thread):
         self.start()
         SubscriberWindows(video_sources=[self.cam_id], callbacks=callbacks).loop()
         self.join()
+        if self.exception_raised is not None:
+            raise self.exception_raised

cvpubsubs/window_sub/cv_window_sub.py

@@ -40,9 +40,9 @@ class SubscriberWindows(object):
     @staticmethod
     def set_global_frame_dict(name, *args):
         if len(str(name)) <= 1000:
-            SubscriberWindows.frame_dict[str(name) + "frame"] = [*args]
+            SubscriberWindows.frame_dict[str(name) + "frame"] = list(args)
         elif isinstance(name, np.ndarray):
-            SubscriberWindows.frame_dict[str(hash(str(name))) + "frame"] = [*args]
+            SubscriberWindows.frame_dict[str(hash(str(name))) + "frame"] = list(args)
         else:
             raise ValueError("Input window name too long.")
 
@@ -68,6 +68,8 @@ class SubscriberWindows(object):
                 )
 
     def _display_frames(self, frames, win_num):
+        if isinstance(frames, Exception):
+            raise frames
         for f in range(len(frames)):
             # detect nested:
             if isinstance(frames[f], (list, tuple)) or frames[f].dtype.num == 17 or len(frames[f].shape) > 3:

tests/test_sub_win.py

@@ -1,8 +1,6 @@
 import threading
 import unittest as ut
 
-import numpy as np
-
 import cvpubsubs.webcam_pub as w
 from cvpubsubs.window_sub import SubscriberWindows
 from cvpubsubs.window_sub.winctrl import WinCtrl
@@ -61,6 +59,16 @@ class TestSubWin(ut.TestCase):
 
         w.VideoHandlerThread(callbacks=redden_frame_print_spam).display()
 
+    def test_sub_with_callback_exception(self):
+        def redden_frame_print_spam(frame, cam_id):
+            frame[:, :, 0] = 0
+            frame[:, :, 2] = 1 / 0
+
+        with self.assertRaises(ZeroDivisionError) as e:
+            v = w.VideoHandlerThread(callbacks=redden_frame_print_spam)
+            v.display()
+            self.assertEqual(v.exception_raised, e)
+
     def test_multi_cams_one_source(self):
         def cam_handler(frame, cam_id):
             SubscriberWindows.set_global_frame_dict(cam_id, frame, frame)
@@ -108,9 +116,26 @@ class TestSubWin(ut.TestCase):
 
         v.join()
 
+    def test_nested_frames_exception(self):
+        def nest_frame(frame, cam_id):
+            frame = np.asarray([[[[[[frame + 1 / 0]]]]], [[[[[frame]]], [[[frame]]]]]])
+            return frame
+
+        v = w.VideoHandlerThread(callbacks=[nest_frame] + w.display_callbacks)
+        v.start()
+
+        with self.assertRaises(ZeroDivisionError) as e:
+            SubscriberWindows(window_names=[str(i) for i in range(3)],
+                              video_sources=[str(0)]
+                              ).loop()
+            self.assertEqual(v.exception_raised, e)
+
+        v.join()
+
     def test_conway_life(self):
         from cvpubsubs.webcam_pub import VideoHandlerThread
-        from cvpubsubs.webcam_pub.callbacks import function_display_callback
+        from cvpubsubs.callbacks import function_display_callback
+        import numpy as np
         img = np.zeros((50, 50, 1))
         img[0:5, 0:5, :] = 1