team-10/env/Lib/site-packages/streamlit/watcher/local_sources_watcher.py
2025-08-02 07:34:44 +02:00

282 lines
11 KiB
Python

# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022-2025)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
import os
import sys
from typing import TYPE_CHECKING, Any, Callable, Final, NamedTuple
from streamlit import config, file_util
from streamlit.logger import get_logger
from streamlit.watcher.folder_black_list import FolderBlackList
from streamlit.watcher.path_watcher import (
NoOpPathWatcher,
get_default_path_watcher_class,
)
if TYPE_CHECKING:
from types import ModuleType
from streamlit.runtime.pages_manager import PagesManager
_LOGGER: Final = get_logger(__name__)
class WatchedModule(NamedTuple):
watcher: Any
module_name: Any
# This needs to be initialized lazily to avoid calling config.get_option() and
# thus initializing config options when this file is first imported.
PathWatcher = None
class LocalSourcesWatcher:
def __init__(self, pages_manager: PagesManager) -> None:
self._pages_manager = pages_manager
self._main_script_path = os.path.realpath(self._pages_manager.main_script_path)
self._watch_folders = config.get_option("server.folderWatchList")
self._script_folder = os.path.dirname(self._main_script_path)
self._on_path_changed: list[Callable[[str], None]] = []
self._is_closed = False
self._cached_sys_modules: set[str] = set()
# Blacklist for folders that should not be watched
self._folder_black_list = FolderBlackList(
config.get_option("server.folderWatchBlacklist")
)
self._watched_modules: dict[str, WatchedModule] = {}
self._watched_pages: set[str] = set()
self.update_watched_pages()
def update_watched_pages(self) -> None:
old_page_paths = self._watched_pages.copy()
new_pages_paths: set[str] = set()
for page_info in self._pages_manager.get_pages().values():
if not page_info["script_path"]:
continue
page_path = os.path.realpath(page_info["script_path"])
new_pages_paths.add(page_path)
if page_path not in self._watched_pages:
self._register_watcher(
page_path,
module_name=None,
)
# Add custom watch path if it exists
for watch_folder in self._watch_folders:
# check if it is folder
if not os.path.isdir(watch_folder):
_LOGGER.warning("Watch folder is not a directory: %s", watch_folder)
continue
_LOGGER.debug("Registering watch folder: %s", watch_folder)
watch_folder_path = os.path.realpath(watch_folder)
if watch_folder_path not in self._watched_pages:
self._register_watcher(
watch_folder_path,
module_name=None,
is_directory=True,
)
for old_page_path in old_page_paths:
# Only remove pages that are no longer valid files
if old_page_path not in new_pages_paths and not os.path.isfile(
old_page_path
):
self._deregister_watcher(old_page_path)
self._watched_pages.remove(old_page_path)
self._watched_pages = self._watched_pages.union(new_pages_paths)
def register_file_change_callback(self, cb: Callable[[str], None]) -> None:
self._on_path_changed.append(cb)
def on_path_changed(self, filepath: str) -> None:
_LOGGER.debug("Path changed: %s", filepath)
norm_filepath = os.path.realpath(filepath)
if norm_filepath not in self._watched_modules:
# Check if this is a file in a watched directory
for watched_path in self._watched_modules:
if (
os.path.isdir(watched_path)
and os.path.commonpath([watched_path, norm_filepath])
== watched_path
):
_LOGGER.debug("File changed in watched directory: %s", filepath)
for cb in self._on_path_changed:
cb(filepath)
return
_LOGGER.error("Received event for non-watched path: %s", filepath)
return
# Workaround:
# Delete all watched modules so we can guarantee changes to the
# updated module are reflected on reload.
#
# In principle, for reloading a given module, we only need to unload
# the module itself and all of the modules which import it (directly
# or indirectly) such that when we exec the application code, the
# changes are reloaded and reflected in the running application.
#
# However, determining all import paths for a given loaded module is
# non-trivial, and so as a workaround we simply unload all watched
# modules.
for wm in self._watched_modules.values():
if wm.module_name is not None and wm.module_name in sys.modules:
del sys.modules[wm.module_name]
for cb in self._on_path_changed:
cb(filepath)
def close(self) -> None:
for wm in self._watched_modules.values():
wm.watcher.close()
self._watched_modules = {}
self._watched_pages = set()
self._is_closed = True
def _register_watcher(
self, filepath: str, module_name: str | None, is_directory: bool = False
) -> None:
global PathWatcher # noqa: PLW0603
if PathWatcher is None:
PathWatcher = get_default_path_watcher_class()
if PathWatcher is NoOpPathWatcher:
return
try:
# Instead of using **kwargs, explicitly pass the named parameters
glob_pattern = "**/*" if is_directory else None
wm = WatchedModule(
watcher=PathWatcher(
filepath,
self.on_path_changed,
glob_pattern=glob_pattern, # Pass as named parameter
allow_nonexistent=False,
),
module_name=module_name,
)
self._watched_modules[filepath] = wm
except Exception as ex:
# If we don't have permission to read this file, or if the file
# doesn't exist, don't even add it to watchers.
_LOGGER.warning("Failed to watch file %s: %s", filepath, exc_info=ex)
return
def _deregister_watcher(self, filepath: str) -> None:
if filepath not in self._watched_modules:
return
if filepath == self._main_script_path:
return
wm = self._watched_modules[filepath]
wm.watcher.close()
del self._watched_modules[filepath]
def _file_is_new(self, filepath: str) -> bool:
return filepath not in self._watched_modules
def _file_should_be_watched(self, filepath: str) -> bool:
# Using short circuiting for performance.
return self._file_is_new(filepath) and (
file_util.file_is_in_folder_glob(filepath, self._script_folder)
or file_util.file_in_pythonpath(filepath)
)
def update_watched_modules(self) -> None:
if self._is_closed:
return
if set(sys.modules) != self._cached_sys_modules:
modules_paths = {
name: self._exclude_blacklisted_paths(get_module_paths(module))
for name, module in dict(sys.modules).items()
}
self._cached_sys_modules = set(sys.modules)
self._register_necessary_watchers(modules_paths)
def _register_necessary_watchers(self, module_paths: dict[str, set[str]]) -> None:
for name, paths in module_paths.items():
for path in paths:
if self._file_should_be_watched(path):
self._register_watcher(os.path.realpath(path), name)
def _exclude_blacklisted_paths(self, paths: set[str]) -> set[str]:
return {p for p in paths if not self._folder_black_list.is_blacklisted(p)}
def get_module_paths(module: ModuleType) -> set[str]:
paths_extractors: list[Callable[[ModuleType], list[str | None]]] = [
# https://docs.python.org/3/reference/datamodel.html
# __file__ is the pathname of the file from which the module was loaded
# if it was loaded from a file.
# The __file__ attribute may be missing for certain types of modules
lambda m: [m.__file__] if hasattr(m, "__file__") else [],
# https://docs.python.org/3/reference/import.html#__spec__
# The __spec__ attribute is set to the module spec that was used
# when importing the module. one exception is __main__,
# where __spec__ is set to None in some cases.
# https://www.python.org/dev/peps/pep-0451/#id16
# "origin" in an import context means the system
# (or resource within a system) from which a module originates
# ... It is up to the loader to decide on how to interpret
# and use a module's origin, if at all.
lambda m: [m.__spec__.origin]
if hasattr(m, "__spec__") and m.__spec__ is not None
else [],
# https://www.python.org/dev/peps/pep-0420/
# Handling of "namespace packages" in which the __path__ attribute
# is a _NamespacePath object with a _path attribute containing
# the various paths of the package.
lambda m: list(m.__path__._path)
if hasattr(m, "__path__")
# This check prevents issues with torch classes:
# https://github.com/streamlit/streamlit/issues/10992
and type(m.__path__).__name__ == "_NamespacePath"
and hasattr(m.__path__, "_path")
else [],
]
all_paths = set()
for extract_paths in paths_extractors:
potential_paths = []
try:
potential_paths = extract_paths(module)
except AttributeError:
# Some modules might not have __file__ or __spec__ attributes.
pass
except Exception:
_LOGGER.warning(
"Examining the path of %s raised:", module.__name__, exc_info=True
)
all_paths.update(
[os.path.realpath(str(p)) for p in potential_paths if _is_valid_path(p)]
)
return all_paths
def _is_valid_path(path: str | None) -> bool:
return isinstance(path, str) and (os.path.isfile(path) or os.path.isdir(path))