defining busy state for SharedObject. Defining SharedObjectBusy exception. Raising this exception when trying to get image from a busy shared object.

1 files changed, 22 insertions, 2 deletions

diff --git a/src/argaze/DataFeatures.py b/src/argaze/DataFeatures.py
index da158be..946b289 100644
--- a/src/argaze/DataFeatures.py
+++ b/src/argaze/DataFeatures.py
@@ -616,6 +616,19 @@ class SharedObject():
 
 		self._lock = threading.Lock()
 
+	def busy(self) -> bool:
+		"""Return lock state."""
+
+		return self._lock.locked()
+
+class SharedObjectBusy(Exception):
+	"""
+	Exception to raised when a shared object is locked.
+	"""
+
+	def __init__(self, message):
+		super().__init__(message)
+
 @timestamp
 class TimestampedException(Exception):
 	"""Enable timestamp management for exception."""
@@ -750,8 +763,7 @@ def PipelineStepAttributeSetter(method):
 
 		except KeyError:
 
-			raise (
-				PipelineStepLoadingFailed(f'Annotations are missing for {method.__name__}: {method.__annotations__}'))
+			raise (PipelineStepLoadingFailed(f'Annotations are missing for {method.__name__}: {method.__annotations__}'))
 
 		logging.debug('%s@%s.setter', get_class_path(self), method.__name__)
 		logging.debug('\t> set %s with %s', expected_value_type.__name__, new_value_type.__name__)
@@ -813,6 +825,14 @@ def PipelineStepImage(method):
 	def wrapper(self, **kwargs) -> numpy.array:
 		"""Wrap pipeline step image method."""
 
+		# Check shared object instance
+		if issubclass(type(self), SharedObject):
+
+			# Busy shared object can't return image
+			if self.busy():
+
+				raise SharedObjectBusy(f'Can\'t return image because {self.name} is busy.')
+
 		if kwargs:
 
 			logging.debug('\t> using kwargs')