1 files changed, 41 insertions, 5 deletions

diff --git a/src/argaze/DataFeatures.py b/src/argaze/DataFeatures.py
index 43e7ea7..1334961 100644
--- a/src/argaze/DataFeatures.py
+++ b/src/argaze/DataFeatures.py
@@ -566,7 +566,7 @@ class PipelineStepObject():
                 filepath = os.path.join(working_directory, new_observers_value)
                 file_format = filepath.split('.')[-1]
 
-                # Python file format
+                # Load module from working directory
                 if file_format == 'py':
 
                     observer_module_path = new_observers_value.split('.')[0]
@@ -744,16 +744,18 @@ class PipelineStepObject():
     def children(self) -> object:
         """Iterate over children pipeline step objects."""
 
-        for name, item in self.__class__.__dict__.items(): 
+        for name in dir(self):
 
-            if isinstance(item, property):
+            if not name.startswith('_'):
 
                 attr = getattr(self, name)
 
-                if PipelineStepObject in attr.__class__.__bases__:
+                if isinstance(attr, PipelineStepObject) and attr != self.parent:
 
-                    yield attr
+                    print('-', name, type(attr))
 
+                    yield attr
+  
 def PipelineStepMethod(method):
     """Define a decorator use into PipelineStepObject class to declare pipeline method.
 
@@ -843,4 +845,38 @@ class PipelineStepObserver():
         !!! warning
             This method is called provided that the observed PipelineStepObject is created as a context using a with statement.
         """
+        pass
+
+class PipelineInputProvider(PipelineStepObject):
+    """
+    Define class to ...
+    """
+    def __init__(self, **kwargs):
+
+        # DEBUG
+        print('PipelineInputProvider.__init__')
+
+        super().__init__(**kwargs)
+
+    def attach(self, method):
+
+        # DEBUG
+        print('PipelineInputProvider.attach', method)
+
+    def __enter__(self):
+        """
+        Define abstract __enter__ method to use device as a context.
+
+        !!! warning
+            This method is called provided that the PipelineInputProvider is created as a context using a with statement.
+        """
+        return self
+
+    def __exit__(self, type, value, traceback):
+        """
+        Define abstract __exit__ method to use device as a context.
+
+        !!! warning
+            This method is called provided that the PipelineInputProvider is created as a context using a with statement.
+        """
         pass
\ No newline at end of file