#16: Inited the filtering functionality

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "notifykit_lib"
-version = "0.0.7-alpha.1"
+version = "0.0.8-alpha.1"
 edition = "2021"
 license = "A toolkit for building applications watching filesystem changes"
 homepage = "https://github.com/roma-glushko/notifykit"

notifykit/__init__.py

@@ -1,4 +1,5 @@
-from notifykit._notifier import Notifier, NotifierT, Event
+from notifykit._filters import EventFilter, CommonFilter
+from notifykit._notifier import Notifier, NotifierT
 from notifykit._notifykit_lib import (
     __version__,
     ObjectType,
@@ -17,13 +18,16 @@
 )
 
 from notifykit._testing import NotifierMock
+from notifykit._typing import Event
 
 VERSION = __version__
 
 __all__ = (
     "Notifier",
     "NotifierT",
     "VERSION",
+    "EventFilter",
+    "CommonFilter",
     "Event",
     "ObjectType",
     "AccessType",

notifykit/_filters.py

@@ -0,0 +1,96 @@
+import re
+from pathlib import Path
+from typing import Sequence, Union
+
+from notifykit._notifykit_lib import RenameEvent
+
+from notifykit._typing import Event
+
+
+class EventFilter:
+    """
+    A base class to define rules to filter filesystem events
+    TODO: Move filtering to the Rust library
+    """
+
+    __slots__ = "_ignore_dirs", "_ignore_object_regexes", "_ignore_paths"
+
+    ignore_dirs: Sequence[str] = ()
+    """Full names of directories to ignore like `.git`."""
+
+    ignore_object_patterns: Sequence[str] = ()
+    """
+    Patterns of files or directories to ignore, these are compiled into regexes.
+    """
+
+    ignore_paths: Sequence[Union[str, Path]] = ()
+    """
+    Full paths to ignore, e.g. `/home/users/.cache` or `C:\\Users\\user\\.cache`.
+    """
+
+    def __init__(self) -> None:
+        self._ignore_dirs = set(self.ignore_dirs)
+        self._ignore_object_regexes = tuple(re.compile(r) for r in self.ignore_object_patterns)
+        self._ignore_paths = tuple(map(str, self.ignore_paths))
+
+    def __call__(self, event: Event) -> bool:
+        """
+        Check if event should be filtered (True) or kept in place (False)
+        """
+        if isinstance(event, RenameEvent):
+            return self._should_be_filtered(Path(event.old_path)) and self._should_be_filtered(Path(event.new_path))
+
+        return self._should_be_filtered(Path(event.path))
+
+    def _should_be_filtered(self, path: Path) -> bool:
+        if any(p in self._ignore_dirs for p in path.parts):
+            return True
+
+        object_name = path.name
+
+        if any(r.search(object_name) for r in self._ignore_object_regexes):
+            return True
+
+        if self._ignore_paths:
+            for ignore_path in self._ignore_paths:
+                if path.is_relative_to(ignore_path):
+                    return True
+
+        return False
+
+    def __repr__(self) -> str:
+        args = ", ".join(f"{k}={getattr(self, k, None)!r}" for k in self.__slots__)
+
+        return f"{self.__class__.__name__}({args})"
+
+
+class CommonFilter(EventFilter):
+    """
+    Filter commonly ignored files and directories
+    """
+
+    ignore_dirs: Sequence[str] = (
+        "__pycache__",
+        ".git",
+        ".hg",
+        ".svn",
+        ".tox",
+        ".venv",
+        "site-packages",
+        ".idea",
+        "node_modules",
+        ".mypy_cache",
+        ".ruff_cache",
+        ".pytest_cache",
+        ".hypothesis",
+    )
+
+    ignore_object_patterns: Sequence[str] = (
+        r"\.py[cod]$",
+        r"\.___jb_...___$",
+        r"\.sw.$",
+        "~$",
+        r"^\.\#",
+        r"^\.DS_Store$",
+        r"^flycheck_",
+    )

notifykit/_notifier.py

@@ -1,18 +1,15 @@
 from os import PathLike
 import anyio
+import logging
 from typing import Sequence, Protocol, Optional, List
 from notifykit._notifykit_lib import (
     WatcherWrapper,
-    AccessEvent,
-    CreateEvent,
-    ModifyDataEvent,
-    ModifyMetadataEvent,
-    ModifyOtherEvent,
-    DeleteEvent,
-    RenameEvent,
 )
 
-Event = AccessEvent | CreateEvent | ModifyDataEvent | ModifyMetadataEvent | ModifyOtherEvent | DeleteEvent | RenameEvent
+from notifykit._typing import Event
+from notifykit._filters import EventFilter
+
+logger = logging.getLogger(__name__)
 
 
 class AnyEvent(Protocol):
@@ -51,13 +48,19 @@ class Notifier:
     """
 
     def __init__(
-        self, debounce_ms: int = 200, tick_ms: int = 50, debug: bool = False, stop_event: Optional[AnyEvent] = None
+        self,
+        debounce_ms: int = 200,
+        tick_ms: int = 50,
+        debug: bool = False,
+        filter: Optional[EventFilter] = None,
+        stop_event: Optional[AnyEvent] = None,
     ) -> None:
         self._debounce_ms = debounce_ms
         self._tick_ms = tick_ms
         self._debug = debug
 
         self._watcher = WatcherWrapper(debounce_ms, debug)
+        self._filter = filter
         self._stop_event = stop_event if stop_event else anyio.Event()
 
     def watch(
@@ -89,6 +92,12 @@ def __next__(self) -> List[Event]:
         if events is None:
             raise StopIteration
 
+        if self._filter:
+            if self._debug:
+                logger.debug(f"events before filtering: {events}")
+
+            events = [event for event in events if not self._filter(event)]
+
         return events
 
     async def __anext__(self) -> List[Event]:
@@ -107,4 +116,10 @@ async def __anext__(self) -> List[Event]:
             if events is None:
                 raise StopAsyncIteration
 
+            if self._filter:
+                if self._debug:
+                    logger.debug(f"events before filtering: {events}")
+
+                events = [event for event in events if not self._filter(event)]
+
             return events

notifykit/_testing.py

@@ -1,7 +1,7 @@
 from os import PathLike
 from typing import Sequence, List, Optional
 
-from notifykit import Event
+from notifykit._typing import Event
 from notifykit._notifier import AnyEvent
 
 

notifykit/_typing.py

@@ -0,0 +1,11 @@
+from notifykit._notifykit_lib import (
+    AccessEvent,
+    CreateEvent,
+    ModifyDataEvent,
+    ModifyMetadataEvent,
+    ModifyOtherEvent,
+    DeleteEvent,
+    RenameEvent,
+)
+
+Event = AccessEvent | CreateEvent | ModifyDataEvent | ModifyMetadataEvent | ModifyOtherEvent | DeleteEvent | RenameEvent