Use weakref.proxy where parent=self.

Co-authored-by: Lukas Nickel <lukas.nickel@tu-dortmund.de>
Co-authored-by: Rune Dominik <rune.dominik@tu-dortmund.de>

ctapipe/calib/camera/calibrator.py

@@ -2,8 +2,8 @@
 Definition of the `CameraCalibrator` class, providing all steps needed to apply
 calibration and image extraction, as well as supporting algorithms.
 """
-
 import warnings
+import weakref
 
 import astropy.units as u
 import numpy as np
@@ -131,7 +131,7 @@ def __init__(
         if image_extractor is None:
             for (_, _, name) in self.image_extractor_type:
                 self.image_extractors[name] = ImageExtractor.from_name(
-                    name, subarray=self.subarray, parent=self
+                    name, subarray=self.subarray, parent=weakref.proxy(self)
                 )
         else:
             name = image_extractor.__class__.__name__
@@ -140,7 +140,9 @@ def __init__(
 
         if data_volume_reducer is None:
             self.data_volume_reducer = DataVolumeReducer.from_name(
-                self.data_volume_reducer_type, subarray=self.subarray, parent=self
+                self.data_volume_reducer_type,
+                subarray=self.subarray,
+                parent=weakref.proxy(self),
             )
         else:
             self.data_volume_reducer = data_volume_reducer
@@ -150,7 +152,7 @@ def __init__(
             self.invalid_pixel_handler = InvalidPixelHandler.from_name(
                 self.invalid_pixel_handler_type,
                 subarray=self.subarray,
-                parent=self,
+                parent=weakref.proxy(self),
             )
 
     def _check_r1_empty(self, waveforms):

ctapipe/calib/camera/flatfield.py

@@ -1,7 +1,7 @@
 """
 Factory for the estimation of the flat field coefficients
 """
-
+import weakref
 from abc import abstractmethod
 
 import numpy as np
@@ -95,7 +95,7 @@ def __init__(self, subarray, **kwargs):
         super().__init__(**kwargs)
         # load the waveform charge extractor
         self.extractor = ImageExtractor.from_name(
-            self.charge_product, parent=self, subarray=subarray
+            self.charge_product, parent=weakref.proxy(self), subarray=subarray
         )
 
         self.log.info(f"extractor {self.extractor}")

ctapipe/calib/camera/pedestals.py

@@ -1,7 +1,7 @@
 """
 Factory for the estimation of the flat field coefficients
 """
-
+import weakref
 from abc import abstractmethod
 
 import numpy as np
@@ -122,7 +122,7 @@ def __init__(self, subarray, **kwargs):
 
         # load the waveform charge extractor
         self.extractor = ImageExtractor.from_name(
-            self.charge_product, parent=self, subarray=subarray
+            self.charge_product, parent=weakref.proxy(self), subarray=subarray
         )
         self.log.info(f"extractor {self.extractor}")
 

ctapipe/core/component.py

@@ -125,7 +125,7 @@ def __init__(self, config=None, parent=None, **kwargs):
         parent: Tool or Component
             If a Component is created by another Component or Tool,
             you need to pass the creating Component as parent, e.g.
-            `parent=self`. This makes sure the config is correctly
+            `parent=weakref.proxy(self)`. This makes sure the config is correctly
             handed down to the child components.
             Do not pass config in this case.
         kwargs
@@ -136,7 +136,7 @@ def __init__(self, config=None, parent=None, **kwargs):
         if parent is not None and config is not None:
             raise ValueError(
                 "Only one of `config` or `parent` allowed"
-                " If you create a Component as part of another, give `parent=self`"
+                " If you create a Component as part of another, give `parent=weakref.proxy(self)`"
                 " and not `config`"
             )
 

ctapipe/core/tests/test_component.py

@@ -1,4 +1,5 @@
 import warnings
+import weakref
 from abc import ABC, abstractmethod
 
 import pytest
@@ -48,12 +49,12 @@ class Bottom(Component):
     class Middle(Component):
         def __init__(self, **kwargs):
             super().__init__(**kwargs)
-            self.bottom = Bottom(parent=self)
+            self.bottom = Bottom(parent=weakref.proxy(self))
 
     class Top(Component):
         def __init__(self, **kwargs):
             super().__init__(**kwargs)
-            self.middle = Middle(parent=self)
+            self.middle = Middle(parent=weakref.proxy(self))
 
     # test with root present
     c = Config({"Top": {"Middle": {"Bottom": {"val": 5}}}})
@@ -83,7 +84,7 @@ class ExampleComponent(Component):
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-        self.sub = SubComponent(parent=self)
+        self.sub = SubComponent(parent=weakref.proxy(self))
 
 
 class ExampleSubclass1(ExampleComponent):
@@ -409,7 +410,7 @@ class MyComponent(Component):
 
         def __init__(self, config=None, parent=None):
             super().__init__(config=config, parent=parent)
-            self.sub = SubComponent(parent=self)
+            self.sub = SubComponent(parent=weakref.proxy(self))
 
     comp = MyComponent()
     assert comp.get_current_config() == {
@@ -436,13 +437,13 @@ def __init__(self, **kwargs):
     class Bar(Component):
         def __init__(self, **kwargs):
             super().__init__(**kwargs)
-            self.foo = Foo(parent=self)
+            self.foo = Foo(parent=weakref.proxy(self))
 
     class Baz(Tool):
         name = "baz"
 
         def setup(self):
-            self.bar = Bar(parent=self)
+            self.bar = Bar(parent=weakref.proxy(self))
 
         def start(self):
             pass

ctapipe/core/tests/test_telescope_component.py

@@ -1,4 +1,5 @@
 import tempfile
+import weakref
 from unittest import mock
 
 import pytest
@@ -303,7 +304,9 @@ class TelescopeTool(Tool):
             classes = tool_classes
 
             def setup(self):
-                self.comp = SomeComponent(subarray=mock_subarray, parent=self)
+                self.comp = SomeComponent(
+                    subarray=mock_subarray, parent=weakref.proxy(self)
+                )
 
         tool = TelescopeTool()
         assert run_tool(tool) == 0

ctapipe/core/tests/test_tool.py

@@ -2,6 +2,7 @@
 import logging
 import os
 import tempfile
+import weakref
 from pathlib import Path
 
 import pytest
@@ -113,7 +114,7 @@ class MyTool2(Tool):
         classes = [MyComponent]
 
         def setup(self):
-            self.comp = MyComponent(parent=self)
+            self.comp = MyComponent(parent=weakref.proxy(self))
 
         def start(self):
             pass
@@ -154,14 +155,14 @@ class MyComponent(Component):
 
         def __init__(self, config=None, parent=None):
             super().__init__(config=config, parent=parent)
-            self.sub = SubComponent(parent=self)
+            self.sub = SubComponent(parent=weakref.proxy(self))
 
     class MyTool(Tool):
         description = "test"
         userparam = Float(5.0, help="parameter").tag(config=True)
 
         def setup(self):
-            self.my_comp = MyComponent(parent=self)
+            self.my_comp = MyComponent(parent=weakref.proxy(self))
 
     config = Config()
     config.MyTool.userparam = 2.0
@@ -217,7 +218,7 @@ class MyTool(Tool):
         aliases = Dict({"component_param": "SubComponent.component_param"})
 
         def setup(self):
-            self.sub = SubComponent(parent=self)
+            self.sub = SubComponent(parent=weakref.proxy(self))
 
     config = Config(
         {"MyTool": {"userparam": 12.0}, "SubComponent": {"component_param": 15.0}}

ctapipe/core/tests/test_traits.py

@@ -1,6 +1,7 @@
 import os
 import pathlib
 import tempfile
+import weakref
 from abc import ABCMeta, abstractmethod
 from unittest import mock
 
@@ -303,7 +304,7 @@ class MyComponent(Component):
 
         def __init__(self, **kwargs):
             super().__init__(**kwargs)
-            self.base = Base.from_name(self.base_name, parent=self)
+            self.base = Base.from_name(self.base_name, parent=weakref.proxy(self))
             self.base.stuff()
 
     class MyListComponent(Component):
@@ -319,7 +320,8 @@ def __init__(self, **kwargs):
 
             if self.base_names is not None:
                 self.bases = [
-                    Base.from_name(name, parent=self) for name in self.base_names
+                    Base.from_name(name, parent=weakref.proxy(self))
+                    for name in self.base_names
                 ]
 
             for base in self.bases:

ctapipe/core/tool.py

@@ -106,15 +106,15 @@ class MyTool(Tool):
                                  allow_none=False).tag(config=True)
 
             def setup(self):
-                self.comp = MyComponent(self, parent=self)
-                self.comp2 = SecondaryMyComponent(self, parent=self)
+                self.comp = MyComponent(self, parent=weakref.proxy(self))
+                self.comp2 = SecondaryMyComponent(self, parent=weakref.proxy(self))
 
                 # correct use of component that is a context manager
                 # using it like this makes sure __exit__ will be called
                 # at the end of Tool.run, even in case of exceptions
-                self.comp3 = self.enter_context(MyComponent(parent=self))
+                self.comp3 = self.enter_context(MyComponent(parent=weakref.proxy(self)))
 
-                self.advanced = AdvancedComponent(parent=self)
+                self.advanced = AdvancedComponent(parent=weakref.proxy(self))
 
             def start(self):
                 self.log.info("Performing {} iterations..."\
@@ -318,7 +318,7 @@ def add_component(self, component_instance):
         --------
         .. code-block:: python3
 
-            self.mycomp = self.add_component(MyComponent(parent=self))
+            self.mycomp = self.add_component(MyComponent(parent=weakref.proxy(self)))
 
         """
         self._registered_components.append(component_instance)

ctapipe/image/extractor.py

@@ -20,6 +20,7 @@
 ]
 
 
+import weakref
 from abc import abstractmethod
 from functools import lru_cache
 from typing import Tuple
@@ -891,7 +892,7 @@ def __init__(self, subarray, **kwargs):
             self.invalid_pixel_handler = InvalidPixelHandler.from_name(
                 self.invalid_pixel_handler_type,
                 self.subarray,
-                parent=self,
+                parent=weakref.proxy(self),
             )
 
     @lru_cache(maxsize=4096)

ctapipe/image/image_processor.py

@@ -1,6 +1,7 @@
 """
 High level image processing  (ImageProcessor Component)
 """
+import weakref
 from copy import deepcopy
 
 import numpy as np
@@ -99,11 +100,11 @@ def __init__(
         super().__init__(subarray=subarray, config=config, parent=parent, **kwargs)
         self.subarray = subarray
         self.clean = ImageCleaner.from_name(
-            self.image_cleaner_type, subarray=subarray, parent=self
+            self.image_cleaner_type, subarray=subarray, parent=weakref.proxy(self)
         )
-        self.modify = ImageModifier(subarray=subarray, parent=self)
+        self.modify = ImageModifier(subarray=subarray, parent=weakref.proxy(self))
 
-        self.check_image = ImageQualityQuery(parent=self)
+        self.check_image = ImageQualityQuery(parent=weakref.proxy(self))
 
         self.default_image_container = DEFAULT_IMAGE_PARAMETERS_CAMFRAME
         if self.use_telescope_frame:

ctapipe/image/reducer.py

@@ -1,6 +1,7 @@
 """
 Algorithms for the data volume reduction.
 """
+import weakref
 from abc import abstractmethod
 
 import numpy as np
@@ -162,15 +163,17 @@ def __init__(
         super().__init__(config=config, parent=parent, subarray=subarray, **kwargs)
 
         if cleaner is None:
-            self.cleaner = TailcutsImageCleaner(parent=self, subarray=self.subarray)
+            self.cleaner = TailcutsImageCleaner(
+                parent=weakref.proxy(self), subarray=self.subarray
+            )
         else:
             self.cleaner = cleaner
 
         self.image_extractors = {}
         if image_extractor is None:
             for (_, _, name) in self.image_extractor_type:
                 self.image_extractors[name] = ImageExtractor.from_name(
-                    name, subarray=self.subarray, parent=self
+                    name, subarray=self.subarray, parent=weakref.proxy(self)
                 )
         else:
             name = image_extractor.__class__.__name__

ctapipe/io/datawriter.py

@@ -3,8 +3,8 @@
 Class to write DL1 (a,b) and DL2 (a) data from an event stream
 """
 
-
 import pathlib
+import weakref
 from collections import defaultdict
 from typing import List
 
@@ -149,7 +149,7 @@ class DataWriter(Component):
 
     .. code-block:: python
 
-        with DataWriter(parent=self) as write_data:
+        with DataWriter(parent=weakref.proxy(self)) as write_data:
             for event in source:
                 calibrate(event)
                 process_images(event)
@@ -251,8 +251,8 @@ def __init__(self, event_source: EventSource, config=None, parent=None, **kwargs
         super().__init__(config=config, parent=parent, **kwargs)
 
         self.event_source = event_source
-        self.contact_info = meta.Contact(parent=self)
-        self.instrument_info = meta.Instrument(parent=self)
+        self.contact_info = meta.Contact(parent=weakref.proxy(self))
+        self.instrument_info = meta.Instrument(parent=weakref.proxy(self))
 
         self._at_least_one_event = False
         self._is_simulation = event_source.is_simulation
@@ -411,7 +411,7 @@ def _setup_writer(self):
         """
         writer = HDF5TableWriter(
             str(self.output_path),
-            parent=self,
+            parent=weakref.proxy(self),
             mode="a",
             add_prefix=True,
             filters=self._hdf5_filters,

ctapipe/io/eventsource.py

@@ -50,7 +50,7 @@ class EventSource(Component):
     An ``EventSource`` can also be created through the configuration system,
     by passing ``config`` or ``parent`` as appropriate.
     E.g. if using ``EventSource`` inside of a ``Tool``, you would do:
-    >>> self.source = EventSource(parent=self) # doctest: +SKIP
+    >>> self.source = EventSource(parent=weakref.proxy(self)) # doctest: +SKIP
 
     To loop through the events in a file:
     >>> source = EventSource(input_url="dataset://gamma_prod5.simtel.zst", max_events=2)

ctapipe/io/simteleventsource.py

@@ -1,5 +1,6 @@
 import enum
 import warnings
+import weakref
 from contextlib import nullcontext
 from enum import Enum, auto, unique
 from gzip import GzipFile
@@ -520,7 +521,7 @@ def __init__(self, input_url=Undefined, config=None, parent=None, **kwargs):
         self.start_pos = self.file_.tell()
 
         self.gain_selector = GainSelector.from_name(
-            self.gain_selector_type, parent=self
+            self.gain_selector_type, parent=weakref.proxy(self)
         )
 
         self._atmosphere_density_profile = read_atmosphere_profile_from_simtel(