1 files changed, 55 insertions, 3 deletions
diff --git a/src/argaze/__main__.py b/src/argaze/__main__.py
index c80657e..9bcbe5a 100644
--- a/src/argaze/__main__.py
+++ b/src/argaze/__main__.py
@@ -18,7 +18,9 @@ __license__ = "GPLv3"
 
 import argparse
 import logging
+import json
 import contextlib
+import os
 
 from . import load
 from .ArFeatures import ArCamera, ArContext
@@ -28,33 +30,64 @@ import cv2
 # Manage arguments
 parser = argparse.ArgumentParser(description=__doc__.split('-')[0])
 parser.add_argument('context_file', metavar='CONTEXT_FILE', type=str, help='JSON context filepath')
-parser.add_argument('-v', '--verbose', action='store_true', default=False,
-                    help='enable verbose mode to print information in console')
+parser.add_argument('-v', '--verbose', action='store_true', default=False, help='enable verbose mode to print information in console')
+parser.add_argument('-p', '--pipe_path', metavar='PIPE_PATH', type=str, default=None, help='enable pipe communication at given path to execute external commands')
 
 args = parser.parse_args()
 
 # Manage logging
 logging.basicConfig(format='%(levelname)s: %(message)s', level=logging.DEBUG if args.verbose else logging.INFO)
 
+# Manage pipe communication
+if args.pipe_path is not None:
+
+	if not os.path.exists(args.pipe_path):
+
+	    os.mkfifo(args.pipe_path)
+
+	# Open the fifo in non-blocking mode or it will stalls until someone opens it for writting
+	pipe_file = os.open(args.pipe_path, os.O_RDONLY | os.O_NONBLOCK)
+
+	logging.info('%s pipe opened', args.pipe_path)
+
 # Load context from JSON file
 with load(args.context_file) as context:
 
 	# Loaded object must be a subclass of ArContext
 	if not issubclass(type(context), ArContext):
+
 		raise TypeError('Loaded object is not a subclass of ArContext')
 
 	if args.verbose:
+
 		print(context)
 
 	# Create a window to display context
 	cv2.namedWindow(context.name, cv2.WINDOW_AUTOSIZE)
 
 	# Waiting for 'ctrl+C' interruption
-	with contextlib.suppress(KeyboardInterrupt):
+	with contextlib.suppress(KeyboardInterrupt), os.fdopen(pipe_file) if args.pipe_path is not None else contextlib.nullcontext() as pipe:
 
 		# Visualization loop
 		while True:
 
+			# Read message from pipe if required
+			if args.pipe_path is not None:
+
+				message = pipe.read().rstrip('\n')
+
+				if message:
+
+					logging.info('%s: %s', args.pipe_path, message)
+
+					try:
+
+						exec(message)
+
+					except Exception as e:
+
+						logging.error('%s', e)
+
 			# Display context
 			cv2.imshow(context.name, context.image())
 
@@ -62,6 +95,7 @@ with load(args.context_file) as context:
 			if issubclass(type(context.pipeline), ArCamera):
 
 				for scene_frame in context.pipeline.scene_frames():
+
 					cv2.imshow(scene_frame.name, scene_frame.image())
 
 			# Key interaction
@@ -69,7 +103,25 @@ with load(args.context_file) as context:
 
 			# Esc: close window
 			if key_pressed == 27:
+
 				raise KeyboardInterrupt()
 
+			# Space bar: pause/resume pipeline processing
+			if key_pressed == 32:
+
+				try:
+
+					if context.is_paused():
+
+						context.resume()
+
+					else:
+
+						context.pause()
+
+				except NotImplementedError:
+
+					pass
+
 	# Stop frame display
 	cv2.destroyAllWindows()