Create inotify module with unit tests

lib/tfw/components/inotify/__init__.py

@@ -0,0 +1,6 @@
+from .inotify import InotifyObserver
+from .inotify import (
+    InotifyFileCreatedEvent, InotifyFileModifiedEvent, InotifyFileMovedEvent,
+    InotifyFileDeletedEvent, InotifyDirCreatedEvent, InotifyDirModifiedEvent,
+    InotifyDirMovedEvent, InotifyDirDeletedEvent
+)

lib/tfw/components/inotify/inotify.py

@@ -0,0 +1,168 @@
+# pylint: disable=too-few-public-methods
+
+from time import time
+
+from watchdog.observers import Observer
+from watchdog.events import FileSystemMovedEvent, PatternMatchingEventHandler
+from watchdog.events import (
+    FileCreatedEvent, FileModifiedEvent, FileMovedEvent, FileDeletedEvent,
+    DirCreatedEvent, DirModifiedEvent, DirMovedEvent, DirDeletedEvent
+)
+
+
+class InotifyEvent:
+    def __init__(self, src_path):
+        self.date = time()
+        self.src_path = src_path
+
+    def __str__(self):
+        return self.__repr__()
+
+    def __repr__(self):
+        return f'{self.date}\t{self.__class__.__name__}:\t{self.src_path}'
+
+
+class InotifyMovedEvent(InotifyEvent):
+    def __init__(self, src_path, dest_path):
+        self.dest_path = dest_path
+        super().__init__(src_path)
+
+    def __repr__(self):
+        return super().__repr__()+f'\t-> {self.dest_path}'
+
+
+class InotifyFileCreatedEvent(InotifyEvent):
+    pass
+
+
+class InotifyFileModifiedEvent(InotifyEvent):
+    pass
+
+
+class InotifyFileMovedEvent(InotifyMovedEvent):
+    pass
+
+
+class InotifyFileDeletedEvent(InotifyEvent):
+    pass
+
+
+class InotifyDirCreatedEvent(InotifyEvent):
+    pass
+
+
+class InotifyDirModifiedEvent(InotifyEvent):
+    pass
+
+
+class InotifyDirMovedEvent(InotifyMovedEvent):
+    pass
+
+
+class InotifyDirDeletedEvent(InotifyEvent):
+    pass
+
+
+class InotifyObserver:
+    def __init__(self, path, patterns=None, exclude=None):
+        self._path = path
+        self._patterns = patterns
+        self._exclude = exclude
+        self.observer = Observer()
+        self.reset(path, patterns, exclude)
+
+    def reset(self, path, patterns, exclude):
+        dispatch_event = self.dispatch_event
+        class TransformerEventHandler(PatternMatchingEventHandler):
+            def on_any_event(self, event):
+                dispatch_event(event)
+        self.handler = TransformerEventHandler(patterns, exclude)
+        self.observer.unschedule_all()
+        self.observer.schedule(self.handler, path, recursive=True)
+
+    @property
+    def path(self):
+        return self._path
+
+    @path.setter
+    def path(self, path):
+        self._path = path
+        self.reset(path, self._patterns, self._exclude)
+
+    @property
+    def patterns(self):
+        return self._patterns
+
+    @patterns.setter
+    def patterns(self, patterns):
+        self._patterns = patterns
+        self.reset(self._path, patterns, self._exclude)
+
+    @property
+    def exclude(self):
+        return self._exclude
+
+    @exclude.setter
+    def exclude(self, exclude):
+        self._exclude = exclude
+        self.reset(self._path, self._patterns, exclude)
+
+    def start(self):
+        self.observer.start()
+
+    def stop(self):
+        self.observer.stop()
+        self.observer.join()
+
+    def dispatch_event(self, event):
+        event_to_action = {
+            InotifyFileCreatedEvent  : self.on_created,
+            InotifyFileModifiedEvent : self.on_modified,
+            InotifyFileMovedEvent    : self.on_moved,
+            InotifyFileDeletedEvent  : self.on_deleted,
+            InotifyDirCreatedEvent   : self.on_created,
+            InotifyDirModifiedEvent  : self.on_modified,
+            InotifyDirMovedEvent     : self.on_moved,
+            InotifyDirDeletedEvent   : self.on_deleted
+        }
+
+        event = self.transform_event(event)
+        self.on_any_event(event)
+        event_to_action[type(event)](event)
+
+    @staticmethod
+    def transform_event(event):
+        watchdog_to_inotify = {
+            FileCreatedEvent  : InotifyFileCreatedEvent,
+            FileModifiedEvent : InotifyFileModifiedEvent,
+            FileMovedEvent    : InotifyFileMovedEvent,
+            FileDeletedEvent  : InotifyFileDeletedEvent,
+            DirCreatedEvent   : InotifyDirCreatedEvent,
+            DirModifiedEvent  : InotifyDirModifiedEvent,
+            DirMovedEvent     : InotifyDirMovedEvent,
+            DirDeletedEvent   : InotifyDirDeletedEvent
+        }
+
+        try:
+            cls = watchdog_to_inotify[type(event)]
+        except KeyError:
+            raise NameError('Watchdog API returned an unknown event.')
+
+        if isinstance(event, FileSystemMovedEvent):
+            return cls(event.src_path, event.dest_path)
+        return cls(event.src_path)
+
+    def on_any_event(self, event):
+        pass
+
+    def on_created(self, event):
+        pass
+
+    def on_modified(self, event):
+        pass
+
+    def on_moved(self, event):
+        pass
+
+    def on_deleted(self, event):
+        pass

lib/tfw/components/inotify/test_inotify.py

@@ -0,0 +1,185 @@
+# pylint: disable=redefined-outer-name
+
+from queue import Empty, Queue
+from secrets import token_urlsafe as random_name
+from pathlib import Path
+from shutil import rmtree
+from os.path import join
+from os import chdir, mkdir, rename, walk, listdir
+from tempfile import TemporaryDirectory
+
+import pytest
+
+from inotify import InotifyObserver
+from inotify import (
+    InotifyFileCreatedEvent, InotifyFileModifiedEvent, InotifyFileMovedEvent,
+    InotifyFileDeletedEvent, InotifyDirCreatedEvent, InotifyDirModifiedEvent,
+    InotifyDirMovedEvent, InotifyDirDeletedEvent
+)
+
+
+class InotifyContext:
+    def __init__(self, folder, observer):
+        self.missing = 0
+        self.folder = folder
+        self.observer = observer
+
+        self.event_to_queue = {
+            InotifyFileCreatedEvent  : self.observer.create_queue,
+            InotifyFileModifiedEvent : self.observer.modify_queue,
+            InotifyFileMovedEvent    : self.observer.move_queue,
+            InotifyFileDeletedEvent  : self.observer.delete_queue,
+            InotifyDirCreatedEvent   : self.observer.create_queue,
+            InotifyDirModifiedEvent  : self.observer.modify_queue,
+            InotifyDirMovedEvent     : self.observer.move_queue,
+            InotifyDirDeletedEvent   : self.observer.delete_queue
+        }
+
+    def random_file(self, dirname, extension):
+        filename = self.join(f'{dirname}/{random_name(16)}{extension}')
+        Path(filename).touch()
+        return filename
+
+    def random_folder(self, basepath):
+        dirname = self.join(f'{basepath}/{random_name(16)}')
+        mkdir(dirname)
+        return dirname
+
+    def join(self, path):
+        return join(self.folder, path)
+
+    def check_event(self, event_type, path):
+        event = self.event_to_queue[event_type].get(timeout=1)
+        assert isinstance(event, event_type)
+        assert event.src_path == path
+        return event
+
+    def check_empty(self, event_type):
+        with pytest.raises(Empty):
+            self.event_to_queue[event_type].get(timeout=1)
+
+    def check_any(self, missing):
+        self.missing += missing
+        attrs = self.observer.__dict__.values()
+        total = sum([q.qsize() for q in attrs if isinstance(q, Queue)])
+        return total+self.missing == len(self.observer.any_list)
+
+
+class InotifyTestObserver(InotifyObserver):
+    def __init__(self, path, patterns=None, exclude=None):
+        self.any_list = []
+        (self.create_queue, self.modify_queue, self.move_queue,
+         self.delete_queue) = [Queue() for _ in range(4)]
+        super().__init__(path, patterns, exclude)
+
+    def on_any_event(self, event):
+        self.any_list.append(event)
+
+    def on_created(self, event):
+        self.create_queue.put(event)
+
+    def on_modified(self, event):
+        self.modify_queue.put(event)
+
+    def on_moved(self, event):
+        self.move_queue.put(event)
+
+    def on_deleted(self, event):
+        self.delete_queue.put(event)
+
+
+@pytest.fixture()
+def context():
+    with TemporaryDirectory() as workdir:
+        chdir(workdir)
+
+        for _ in range(5):
+            newdir = join(workdir, random_name(16))
+            mkdir(newdir)
+            Path(join(newdir, random_name(16)+'.txt')).touch()
+
+        monitor = InotifyTestObserver(workdir)
+        monitor.start()
+        yield InotifyContext(workdir, monitor)
+
+def test_create(context):
+    for _, dirs, _ in list(walk(context.folder)):
+        for name in dirs:
+            newfile = context.random_file(name, '.txt')
+            context.check_event(InotifyFileCreatedEvent, newfile)
+            newdir = context.random_folder(name)
+            context.check_event(InotifyDirCreatedEvent, newdir)
+            assert context.check_any(2)
+
+def test_modify(context):
+    for root, _, files in list(walk(context.folder)):
+        for name in files:
+            oldfile = join(root, name)
+            with open(oldfile, 'w') as ofile:
+                ofile.write('text')
+            context.check_event(InotifyFileModifiedEvent, oldfile)
+            rename(oldfile, oldfile+'_new')
+            context.check_event(InotifyDirModifiedEvent, root)
+            assert context.check_any(2)
+
+def test_move(context):
+    for root, dirs, _ in list(walk(context.folder)):
+        for name in dirs:
+            olddir = join(root, name)
+            oldfile = join(olddir, list(listdir(olddir))[0])
+            rename(olddir, olddir+'_new')
+            context.check_event(InotifyDirMovedEvent, olddir)
+            context.check_event(InotifyFileMovedEvent, oldfile)
+            assert context.check_any(2)
+
+def test_delete(context):
+    for root, dirs, _ in list(walk(context.folder)):
+        for name in dirs:
+            olddir = join(root, name)
+            oldfile = join(olddir, list(listdir(olddir))[0])
+            rmtree(olddir)
+            context.check_event(InotifyFileDeletedEvent, oldfile)
+            context.check_event(InotifyDirDeletedEvent, olddir)
+            assert context.check_any(2)
+
+def test_path(context):
+    for _, dirs, _ in list(walk(context.folder)):
+        for name in dirs:
+            context.observer.path = context.join(name)
+            context.random_folder('.')
+            newfile = context.random_file(name, '.txt')
+            context.check_event(InotifyFileCreatedEvent, newfile)
+            context.observer.path = context.folder
+            assert context.check_any(1)
+
+def test_patterns(context):
+    for _, dirs, _ in list(walk(context.folder)):
+        for name in dirs:
+            context.observer.patterns = ["*.txt"]
+            context.random_file(name, '.bin')
+            newfile = context.random_file(name, '.txt')
+            context.check_event(InotifyFileCreatedEvent, newfile)
+            context.check_empty(InotifyFileCreatedEvent)
+            assert context.check_any(1)
+            context.observer.patterns = None
+
+def test_exclude(context):
+    for _, dirs, _ in list(walk(context.folder)):
+        for name in dirs:
+            context.observer.exclude = ["*.txt"]
+            context.random_file(name, '.txt')
+            newfile = context.random_file(name, '.bin')
+            context.check_event(InotifyFileCreatedEvent, newfile)
+            context.check_empty(InotifyFileCreatedEvent)
+            assert context.check_any(1)
+            context.observer.exclude = None
+
+def test_stress(context):
+    for _, dirs, _ in list(walk(context.folder)):
+        for name in dirs:
+            newfile = []
+            for i in range(1024):
+                newfile.append(context.random_file(name, '.txt'))
+            for i in range(1024):
+                context.check_event(InotifyFileCreatedEvent, newfile[i])
+            assert context.check_any(1024)