Add polling parameters to ConfigManagingActor (#1082)

The ConfigManagingActor now allows to force file polling and set the
polling interval.

Author: llucax

RELEASE_NOTES.md

@@ -10,7 +10,9 @@
 
 ## New Features
 
-<!-- Here goes the main new features and examples or instructions on how to use them -->
+- `ConfigManagingActor`: The file polling mechanism is now forced by default. Two new parameters have been added:
+  - `force_polling`: Whether to force file polling to check for changes. Default is `True`.
+  - `polling_interval`: The interval to check for changes. Only relevant if polling is enabled. Default is 1 second.
 
 ## Bug Fixes
 

pyproject.toml

@@ -30,7 +30,7 @@ dependencies = [
   # changing the version
   # (plugins.mkdocstrings.handlers.python.import)
   "frequenz-client-microgrid >= 0.5.1, < 0.6.0",
-  "frequenz-channels >= 1.1.0, < 2.0.0",
+  "frequenz-channels >= 1.2.0, < 2.0.0",
   "networkx >= 2.8, < 4",
   "numpy >= 1.26.4, < 2",
   "typing_extensions >= 4.6.1, < 5",

src/frequenz/sdk/config/_config_managing.py

@@ -7,6 +7,7 @@
 import pathlib
 import tomllib
 from collections import abc
+from datetime import timedelta
 from typing import Any, assert_never
 
 from frequenz.channels import Sender
@@ -29,13 +30,16 @@ class ConfigManagingActor(Actor):
     reading too.
     """
 
+    # pylint: disable-next=too-many-arguments
     def __init__(
         self,
         config_path: pathlib.Path | str,
         output: Sender[abc.Mapping[str, Any]],
         event_types: abc.Set[EventType] = frozenset(EventType),
         *,
         name: str | None = None,
+        force_polling: bool = True,
+        polling_interval: timedelta = timedelta(seconds=1),
     ) -> None:
         """Initialize this instance.
 
@@ -45,6 +49,9 @@ def __init__(
             event_types: The set of event types to monitor.
             name: The name of the actor. If `None`, `str(id(self))` will
                 be used. This is used mostly for debugging purposes.
+            force_polling: Whether to force file polling to check for changes.
+            polling_interval: The interval to poll for changes. Only relevant if
+                polling is enabled.
         """
         super().__init__(name=name)
         self._config_path: pathlib.Path = (
@@ -54,6 +61,8 @@ def __init__(
         )
         self._output: Sender[abc.Mapping[str, Any]] = output
         self._event_types: abc.Set[EventType] = event_types
+        self._force_polling: bool = force_polling
+        self._polling_interval: timedelta = polling_interval
 
     def _read_config(self) -> abc.Mapping[str, Any]:
         """Read the contents of the configuration file.
@@ -89,7 +98,10 @@ async def _run(self) -> None:
         # parent directory instead just in case a configuration file doesn't exist yet
         # or it is deleted and recreated again.
         file_watcher = FileWatcher(
-            paths=[self._config_path.parent], event_types=self._event_types
+            paths=[self._config_path.parent],
+            event_types=self._event_types,
+            force_polling=self._force_polling,
+            polling_interval=self._polling_interval,
         )
 
         try:

tests/actor/test_config_manager.py

@@ -71,7 +71,9 @@ async def test_update(self, config_file: pathlib.Path) -> None:
         )
         config_receiver = config_channel.new_receiver()
 
-        async with ConfigManagingActor(config_file, config_channel.new_sender()):
+        async with ConfigManagingActor(
+            config_file, config_channel.new_sender(), force_polling=False
+        ):
             config = await config_receiver.receive()
             assert config is not None
             assert config.get("logging_lvl") == "DEBUG"
@@ -100,7 +102,9 @@ async def test_update_relative_path(self, config_file: pathlib.Path) -> None:
         current_dir = pathlib.Path.cwd()
         relative_path = os.path.relpath(config_file, current_dir)
 
-        async with ConfigManagingActor(relative_path, config_channel.new_sender()):
+        async with ConfigManagingActor(
+            relative_path, config_channel.new_sender(), force_polling=False
+        ):
             config = await config_receiver.receive()
             assert config is not None
             assert config.get("var2") is None