Cours/venv/lib/python3.12/site-packages/watchdog/watchmedo.py

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""":module: watchdog.watchmedo
:author: yesudeep@google.com (Yesudeep Mangalapilly)
:author: contact@tiger-222.fr (Mickaël Schoentgen)
:synopsis: ``watchmedo`` shell script utility.
"""
from __future__ import annotations
import errno
import logging
import os
import os.path
import sys
import time
from argparse import ArgumentParser, RawDescriptionHelpFormatter
from io import StringIO
from textwrap import dedent
from typing import TYPE_CHECKING, Any
from watchdog.utils import WatchdogShutdownError, load_class, platform
from watchdog.version import VERSION_STRING
if TYPE_CHECKING:
from argparse import Namespace, _SubParsersAction
from typing import Callable
from watchdog.events import FileSystemEventHandler
from watchdog.observers import ObserverType
from watchdog.observers.api import BaseObserver
logging.basicConfig(level=logging.INFO)
CONFIG_KEY_TRICKS = "tricks"
CONFIG_KEY_PYTHON_PATH = "python-path"
class HelpFormatter(RawDescriptionHelpFormatter):
"""A nicer help formatter.
Help for arguments can be indented and contain new lines.
It will be de-dented and arguments in the help
will be separated by a blank line for better readability.
Source: https://github.com/httpie/httpie/blob/2423f89/httpie/cli/argparser.py#L31
"""
def __init__(self, *args: Any, max_help_position: int = 6, **kwargs: Any) -> None:
# A smaller indent for args help.
kwargs["max_help_position"] = max_help_position
super().__init__(*args, **kwargs)
def _split_lines(self, text: str, width: int) -> list[str]:
text = dedent(text).strip() + "\n\n"
return text.splitlines()
epilog = """\
Copyright 2018-2024 Mickaël Schoentgen & contributors
Copyright 2014-2018 Thomas Amland & contributors
Copyright 2012-2014 Google, Inc.
Copyright 2011-2012 Yesudeep Mangalapilly
Licensed under the terms of the Apache license, version 2.0. Please see
LICENSE in the source code for more information."""
cli = ArgumentParser(epilog=epilog, formatter_class=HelpFormatter)
cli.add_argument("--version", action="version", version=VERSION_STRING)
subparsers = cli.add_subparsers(dest="top_command")
command_parsers = {}
Argument = tuple[list[str], Any]
def argument(*name_or_flags: str, **kwargs: Any) -> Argument:
"""Convenience function to properly format arguments to pass to the
command decorator.
"""
return list(name_or_flags), kwargs
def command(
args: list[Argument],
*,
parent: _SubParsersAction[ArgumentParser] = subparsers,
cmd_aliases: list[str] | None = None,
) -> Callable:
"""Decorator to define a new command in a sanity-preserving way.
The function will be stored in the ``func`` variable when the parser
parses arguments so that it can be called directly like so::
>>> args = cli.parse_args()
>>> args.func(args)
"""
def decorator(func: Callable) -> Callable:
name = func.__name__.replace("_", "-")
desc = dedent(func.__doc__ or "")
parser = parent.add_parser(name, aliases=cmd_aliases or [], description=desc, formatter_class=HelpFormatter)
command_parsers[name] = parser
verbosity_group = parser.add_mutually_exclusive_group()
verbosity_group.add_argument("-q", "--quiet", dest="verbosity", action="append_const", const=-1)
verbosity_group.add_argument("-v", "--verbose", dest="verbosity", action="append_const", const=1)
for name_or_flags, kwargs in args:
parser.add_argument(*name_or_flags, **kwargs)
parser.set_defaults(func=func)
return func
return decorator
def path_split(pathname_spec: str, *, separator: str = os.pathsep) -> list[str]:
"""Splits a pathname specification separated by an OS-dependent separator.
:param pathname_spec:
The pathname specification.
:param separator:
(OS Dependent) `:` on Unix and `;` on Windows or user-specified.
"""
return pathname_spec.split(separator)
def add_to_sys_path(pathnames: list[str], *, index: int = 0) -> None:
"""Adds specified paths at specified index into the sys.path list.
:param paths:
A list of paths to add to the sys.path
:param index:
(Default 0) The index in the sys.path list where the paths will be
added.
"""
for pathname in pathnames[::-1]:
sys.path.insert(index, pathname)
def load_config(tricks_file_pathname: str) -> dict:
"""Loads the YAML configuration from the specified file.
:param tricks_file_path:
The path to the tricks configuration file.
:returns:
A dictionary of configuration information.
"""
import yaml
with open(tricks_file_pathname, "rb") as f:
return yaml.safe_load(f.read())
def parse_patterns(
patterns_spec: str, ignore_patterns_spec: str, *, separator: str = ";"
) -> tuple[list[str], list[str]]:
"""Parses pattern argument specs and returns a two-tuple of
(patterns, ignore_patterns).
"""
patterns = patterns_spec.split(separator)
ignore_patterns = ignore_patterns_spec.split(separator)
if ignore_patterns == [""]:
ignore_patterns = []
return patterns, ignore_patterns
def observe_with(
observer: BaseObserver,
event_handler: FileSystemEventHandler,
pathnames: list[str],
*,
recursive: bool,
) -> None:
"""Single observer thread with a scheduled path and event handler.
:param observer:
The observer thread.
:param event_handler:
Event handler which will be called in response to file system events.
:param pathnames:
A list of pathnames to monitor.
:param recursive:
``True`` if recursive; ``False`` otherwise.
"""
for pathname in set(pathnames):
observer.schedule(event_handler, pathname, recursive=recursive)
observer.start()
try:
while True:
time.sleep(1)
except WatchdogShutdownError:
observer.stop()
observer.join()
def schedule_tricks(observer: BaseObserver, tricks: dict, pathname: str, *, recursive: bool) -> None:
"""Schedules tricks with the specified observer and for the given watch
path.
:param observer:
The observer thread into which to schedule the trick and watch.
:param tricks:
A list of tricks.
:param pathname:
A path name which should be watched.
:param recursive:
``True`` if recursive; ``False`` otherwise.
"""
for trick in tricks:
for name, value in trick.items():
trick_cls = load_class(name)
handler = trick_cls(**value)
trick_pathname = getattr(handler, "source_directory", None) or pathname
observer.schedule(handler, trick_pathname, recursive=recursive)
@command(
[
argument("files", nargs="*", help="perform tricks from given file"),
argument(
"--python-path",
default=".",
help=f"Paths separated by {os.pathsep!r} to add to the Python path.",
),
argument(
"--interval",
"--timeout",
dest="timeout",
default=1.0,
type=float,
help="Use this as the polling interval/blocking timeout (in seconds).",
),
argument(
"--recursive",
action="store_true",
default=True,
help="Recursively monitor paths (defaults to True).",
),
argument("--debug-force-polling", action="store_true", help="[debug] Forces polling."),
argument(
"--debug-force-kqueue",
action="store_true",
help="[debug] Forces BSD kqueue(2).",
),
argument(
"--debug-force-winapi",
action="store_true",
help="[debug] Forces Windows API.",
),
argument(
"--debug-force-fsevents",
action="store_true",
help="[debug] Forces macOS FSEvents.",
),
argument(
"--debug-force-inotify",
action="store_true",
help="[debug] Forces Linux inotify(7).",
),
],
cmd_aliases=["tricks"],
)
def tricks_from(args: Namespace) -> None:
"""Command to execute tricks from a tricks configuration file."""
observer_cls: ObserverType
if args.debug_force_polling:
from watchdog.observers.polling import PollingObserver
observer_cls = PollingObserver
elif args.debug_force_kqueue:
from watchdog.observers.kqueue import KqueueObserver
observer_cls = KqueueObserver
elif (not TYPE_CHECKING and args.debug_force_winapi) or (TYPE_CHECKING and platform.is_windows()):
from watchdog.observers.read_directory_changes import WindowsApiObserver
observer_cls = WindowsApiObserver
elif args.debug_force_inotify:
from watchdog.observers.inotify import InotifyObserver
observer_cls = InotifyObserver
elif args.debug_force_fsevents:
from watchdog.observers.fsevents import FSEventsObserver
observer_cls = FSEventsObserver
else:
# Automatically picks the most appropriate observer for the platform
# on which it is running.
from watchdog.observers import Observer
observer_cls = Observer
add_to_sys_path(path_split(args.python_path))
observers = []
for tricks_file in args.files:
observer = observer_cls(timeout=args.timeout)
if not os.path.exists(tricks_file):
raise OSError(errno.ENOENT, os.strerror(errno.ENOENT), tricks_file)
config = load_config(tricks_file)
try:
tricks = config[CONFIG_KEY_TRICKS]
except KeyError as e:
error = f"No {CONFIG_KEY_TRICKS!r} key specified in {tricks_file!r}."
raise KeyError(error) from e
if CONFIG_KEY_PYTHON_PATH in config:
add_to_sys_path(config[CONFIG_KEY_PYTHON_PATH])
dir_path = os.path.dirname(tricks_file) or os.path.relpath(os.getcwd())
schedule_tricks(observer, tricks, dir_path, recursive=args.recursive)
observer.start()
observers.append(observer)
try:
while True:
time.sleep(1)
except WatchdogShutdownError:
for o in observers:
o.unschedule_all()
o.stop()
for o in observers:
o.join()
@command(
[
argument(
"trick_paths",
nargs="*",
help="Dotted paths for all the tricks you want to generate.",
),
argument(
"--python-path",
default=".",
help=f"Paths separated by {os.pathsep!r} to add to the Python path.",
),
argument(
"--append-to-file",
default=None,
help="""
Appends the generated tricks YAML to a file.
If not specified, prints to standard output.""",
),
argument(
"-a",
"--append-only",
dest="append_only",
action="store_true",
help="""
If --append-to-file is not specified, produces output for
appending instead of a complete tricks YAML file.""",
),
],
cmd_aliases=["generate-tricks-yaml"],
)
def tricks_generate_yaml(args: Namespace) -> None:
"""Command to generate Yaml configuration for tricks named on the command line."""
import yaml
python_paths = path_split(args.python_path)
add_to_sys_path(python_paths)
output = StringIO()
for trick_path in args.trick_paths:
trick_cls = load_class(trick_path)
output.write(trick_cls.generate_yaml())
content = output.getvalue()
output.close()
header = yaml.dump({CONFIG_KEY_PYTHON_PATH: python_paths})
header += f"{CONFIG_KEY_TRICKS}:\n"
if args.append_to_file is None:
# Output to standard output.
if not args.append_only:
content = header + content
sys.stdout.write(content)
else:
if not os.path.exists(args.append_to_file):
content = header + content
with open(args.append_to_file, "a", encoding="utf-8") as file:
file.write(content)
@command(
[
argument(
"directories",
nargs="*",
default=".",
help="Directories to watch. (default: '.').",
),
argument(
"-p",
"--pattern",
"--patterns",
dest="patterns",
default="*",
help="Matches event paths with these patterns (separated by ;).",
),
argument(
"-i",
"--ignore-pattern",
"--ignore-patterns",
dest="ignore_patterns",
default="",
help="Ignores event paths with these patterns (separated by ;).",
),
argument(
"-D",
"--ignore-directories",
dest="ignore_directories",
action="store_true",
help="Ignores events for directories.",
),
argument(
"-R",
"--recursive",
dest="recursive",
action="store_true",
help="Monitors the directories recursively.",
),
argument(
"--interval",
"--timeout",
dest="timeout",
default=1.0,
type=float,
help="Use this as the polling interval/blocking timeout.",
),
argument("--trace", action="store_true", help="Dumps complete dispatching trace."),
argument("--debug-force-polling", action="store_true", help="[debug] Forces polling."),
argument(
"--debug-force-kqueue",
action="store_true",
help="[debug] Forces BSD kqueue(2).",
),
argument(
"--debug-force-winapi",
action="store_true",
help="[debug] Forces Windows API.",
),
argument(
"--debug-force-fsevents",
action="store_true",
help="[debug] Forces macOS FSEvents.",
),
argument(
"--debug-force-inotify",
action="store_true",
help="[debug] Forces Linux inotify(7).",
),
],
)
def log(args: Namespace) -> None:
"""Command to log file system events to the console."""
from watchdog.tricks import LoggerTrick
from watchdog.utils import echo
if args.trace:
class_module_logger = logging.getLogger(LoggerTrick.__module__)
echo.echo_class(LoggerTrick, write=lambda msg: class_module_logger.info(msg))
patterns, ignore_patterns = parse_patterns(args.patterns, args.ignore_patterns)
handler = LoggerTrick(
patterns=patterns,
ignore_patterns=ignore_patterns,
ignore_directories=args.ignore_directories,
)
observer_cls: ObserverType
if args.debug_force_polling:
from watchdog.observers.polling import PollingObserver
observer_cls = PollingObserver
elif args.debug_force_kqueue:
from watchdog.observers.kqueue import KqueueObserver
observer_cls = KqueueObserver
elif (not TYPE_CHECKING and args.debug_force_winapi) or (TYPE_CHECKING and platform.is_windows()):
from watchdog.observers.read_directory_changes import WindowsApiObserver
observer_cls = WindowsApiObserver
elif args.debug_force_inotify:
from watchdog.observers.inotify import InotifyObserver
observer_cls = InotifyObserver
elif args.debug_force_fsevents:
from watchdog.observers.fsevents import FSEventsObserver
observer_cls = FSEventsObserver
else:
# Automatically picks the most appropriate observer for the platform
# on which it is running.
from watchdog.observers import Observer
observer_cls = Observer
observer = observer_cls(timeout=args.timeout)
observe_with(observer, handler, args.directories, recursive=args.recursive)
@command(
[
argument("directories", nargs="*", default=".", help="Directories to watch."),
argument(
"-c",
"--command",
dest="command",
default=None,
help="""
Shell command executed in response to matching events.
These interpolation variables are available to your command string:
${watch_src_path} - event source path
${watch_dest_path} - event destination path (for moved events)
${watch_event_type} - event type
${watch_object} - 'file' or 'directory'
Note:
Please ensure you do not use double quotes (") to quote
your command string. That will force your shell to
interpolate before the command is processed by this
command.
Example:
--command='echo "${watch_src_path}"'
""",
),
argument(
"-p",
"--pattern",
"--patterns",
dest="patterns",
default="*",
help="Matches event paths with these patterns (separated by ;).",
),
argument(
"-i",
"--ignore-pattern",
"--ignore-patterns",
dest="ignore_patterns",
default="",
help="Ignores event paths with these patterns (separated by ;).",
),
argument(
"-D",
"--ignore-directories",
dest="ignore_directories",
default=False,
action="store_true",
help="Ignores events for directories.",
),
argument(
"-R",
"--recursive",
dest="recursive",
action="store_true",
help="Monitors the directories recursively.",
),
argument(
"--interval",
"--timeout",
dest="timeout",
default=1.0,
type=float,
help="Use this as the polling interval/blocking timeout.",
),
argument(
"-w",
"--wait",
dest="wait_for_process",
action="store_true",
help="Wait for process to finish to avoid multiple simultaneous instances.",
),
argument(
"-W",
"--drop",
dest="drop_during_process",
action="store_true",
help="Ignore events that occur while command is still being"
" executed to avoid multiple simultaneous instances.",
),
argument("--debug-force-polling", action="store_true", help="[debug] Forces polling."),
],
)
def shell_command(args: Namespace) -> None:
"""Command to execute shell commands in response to file system events."""
from watchdog.tricks import ShellCommandTrick
if not args.command:
args.command = None
observer_cls: ObserverType
if args.debug_force_polling:
from watchdog.observers.polling import PollingObserver
observer_cls = PollingObserver
else:
from watchdog.observers import Observer
observer_cls = Observer
patterns, ignore_patterns = parse_patterns(args.patterns, args.ignore_patterns)
handler = ShellCommandTrick(
args.command,
patterns=patterns,
ignore_patterns=ignore_patterns,
ignore_directories=args.ignore_directories,
wait_for_process=args.wait_for_process,
drop_during_process=args.drop_during_process,
)
observer = observer_cls(timeout=args.timeout)
observe_with(observer, handler, args.directories, recursive=args.recursive)
@command(
[
argument("command", help="Long-running command to run in a subprocess."),
argument(
"command_args",
metavar="arg",
nargs="*",
help="""
Command arguments.
Note: Use -- before the command arguments, otherwise watchmedo will
try to interpret them.
""",
),
argument(
"-d",
"--directory",
dest="directories",
metavar="DIRECTORY",
action="append",
help="Directory to watch. Use another -d or --directory option for each directory.",
),
argument(
"-p",
"--pattern",
"--patterns",
dest="patterns",
default="*",
help="Matches event paths with these patterns (separated by ;).",
),
argument(
"-i",
"--ignore-pattern",
"--ignore-patterns",
dest="ignore_patterns",
default="",
help="Ignores event paths with these patterns (separated by ;).",
),
argument(
"-D",
"--ignore-directories",
dest="ignore_directories",
default=False,
action="store_true",
help="Ignores events for directories.",
),
argument(
"-R",
"--recursive",
dest="recursive",
action="store_true",
help="Monitors the directories recursively.",
),
argument(
"--interval",
"--timeout",
dest="timeout",
default=1.0,
type=float,
help="Use this as the polling interval/blocking timeout.",
),
argument(
"--signal",
dest="signal",
default="SIGINT",
help="Stop the subprocess with this signal (default SIGINT).",
),
argument("--debug-force-polling", action="store_true", help="[debug] Forces polling."),
argument(
"--kill-after",
dest="kill_after",
default=10.0,
type=float,
help="When stopping, kill the subprocess after the specified timeout in seconds (default 10.0).",
),
argument(
"--debounce-interval",
dest="debounce_interval",
default=0.0,
type=float,
help="After a file change, Wait until the specified interval (in "
"seconds) passes with no file changes, and only then restart.",
),
argument(
"--no-restart-on-command-exit",
dest="restart_on_command_exit",
default=True,
action="store_false",
help="Don't auto-restart the command after it exits.",
),
],
)
def auto_restart(args: Namespace) -> None:
"""Command to start a long-running subprocess and restart it on matched events."""
observer_cls: ObserverType
if args.debug_force_polling:
from watchdog.observers.polling import PollingObserver
observer_cls = PollingObserver
else:
from watchdog.observers import Observer
observer_cls = Observer
import signal
from watchdog.tricks import AutoRestartTrick
if not args.directories:
args.directories = ["."]
# Allow either signal name or number.
stop_signal = getattr(signal, args.signal) if args.signal.startswith("SIG") else int(args.signal)
# Handle termination signals by raising a semantic exception which will
# allow us to gracefully unwind and stop the observer
termination_signals = {signal.SIGTERM, signal.SIGINT}
if hasattr(signal, "SIGHUP"):
termination_signals.add(signal.SIGHUP)
def handler_termination_signal(_signum: signal._SIGNUM, _frame: object) -> None:
# Neuter all signals so that we don't attempt a double shutdown
for signum in termination_signals:
signal.signal(signum, signal.SIG_IGN)
raise WatchdogShutdownError
for signum in termination_signals:
signal.signal(signum, handler_termination_signal)
patterns, ignore_patterns = parse_patterns(args.patterns, args.ignore_patterns)
command = [args.command]
command.extend(args.command_args)
handler = AutoRestartTrick(
command,
patterns=patterns,
ignore_patterns=ignore_patterns,
ignore_directories=args.ignore_directories,
stop_signal=stop_signal,
kill_after=args.kill_after,
debounce_interval_seconds=args.debounce_interval,
restart_on_command_exit=args.restart_on_command_exit,
)
handler.start()
observer = observer_cls(timeout=args.timeout)
try:
observe_with(observer, handler, args.directories, recursive=args.recursive)
except WatchdogShutdownError:
pass
finally:
handler.stop()
class LogLevelError(Exception):
pass
def _get_log_level_from_args(args: Namespace) -> str:
verbosity = sum(args.verbosity or [])
if verbosity < -1:
error = "-q/--quiet may be specified only once."
raise LogLevelError(error)
if verbosity > 2:
error = "-v/--verbose may be specified up to 2 times."
raise LogLevelError(error)
return ["ERROR", "WARNING", "INFO", "DEBUG"][1 + verbosity]
def main() -> int:
"""Entry-point function."""
args = cli.parse_args()
if args.top_command is None:
cli.print_help()
return 1
try:
log_level = _get_log_level_from_args(args)
except LogLevelError as exc:
print(f"Error: {exc.args[0]}", file=sys.stderr) # noqa:T201
command_parsers[args.top_command].print_help()
return 1
logging.getLogger("watchdog").setLevel(log_level)
try:
args.func(args)
except KeyboardInterrupt:
return 130
return 0
if __name__ == "__main__":
sys.exit(main())