Use watchfiles as a file watching backend

This doesn't use polling unless absolutely necessarily, making it more efficient. It also reduces the amount of first-party code required, and simplifies working out which files are being watched.
This commit is contained in:
Jake Howard 2023-06-21 22:01:38 +01:00 committed by Deniz Turgut
commit 61ca47c519
No known key found for this signature in database
GPG key ID: 87B7168D7AB3ED2F
4 changed files with 32 additions and 260 deletions

View file

@ -27,7 +27,7 @@ from pelican.plugins._utils import get_plugin_name, load_plugins
from pelican.readers import Readers
from pelican.server import ComplexHTTPRequestHandler, RootedHTTPServer
from pelican.settings import read_settings
from pelican.utils import (FileSystemWatcher, clean_output_dir, maybe_pluralize)
from pelican.utils import (wait_for_changes, clean_output_dir, maybe_pluralize)
from pelican.writers import Writer
try:
@ -452,26 +452,19 @@ def autoreload(args, excqueue=None):
console.print(' --- AutoReload Mode: Monitoring `content`, `theme` and'
' `settings` for changes. ---')
pelican, settings = get_instance(args)
watcher = FileSystemWatcher(args.settings, Readers, settings)
sleep = False
settings_file = os.path.abspath(args.settings)
while True:
try:
# Don't sleep first time, but sleep afterwards to reduce cpu load
if sleep:
time.sleep(0.5)
else:
sleep = True
changed_files = wait_for_changes(args.settings, Readers, settings)
modified = watcher.check()
changed_files = {c[1] for c in changed_files}
if modified['settings']:
if settings_file in changed_files:
pelican, settings = get_instance(args)
watcher.update_watchers(settings)
if any(modified.values()):
console.print('\n-> Modified: {}. re-generating...'.format(
', '.join(k for k, v in modified.items() if v)))
pelican.run()
console.print('\n-> Modified: {}. re-generating...'.format(
', '.join(changed_files)))
pelican.run()
except KeyboardInterrupt:
if excqueue is not None:
@ -558,8 +551,6 @@ def main(argv=None):
listen(settings.get('BIND'), settings.get('PORT'),
settings.get("OUTPUT_PATH"))
else:
watcher = FileSystemWatcher(args.settings, Readers, settings)
watcher.check()
with console.status("Generating..."):
pelican.run()
except KeyboardInterrupt:

View file

@ -412,92 +412,6 @@ class TestUtils(LoggedTestCase):
self.assertNotIn(a_arts[4], b_arts[5].translations)
self.assertNotIn(a_arts[5], b_arts[4].translations)
def test_filesystemwatcher(self):
def create_file(name, content):
with open(name, 'w') as f:
f.write(content)
# disable logger filter
from pelican.utils import logger
logger.disable_filter()
# create a temp "project" dir
root = mkdtemp()
content_path = os.path.join(root, 'content')
static_path = os.path.join(root, 'content', 'static')
config_file = os.path.join(root, 'config.py')
theme_path = os.path.join(root, 'mytheme')
# populate
os.mkdir(content_path)
os.mkdir(theme_path)
create_file(config_file,
'PATH = "content"\n'
'THEME = "mytheme"\n'
'STATIC_PATHS = ["static"]')
t = time.time() - 1000 # make sure it's in the "past"
os.utime(config_file, (t, t))
settings = read_settings(config_file)
watcher = utils.FileSystemWatcher(config_file, Readers, settings)
# should get a warning for static not not existing
self.assertLogCountEqual(1, 'Watched path does not exist: .*static')
# create it and update config
os.mkdir(static_path)
watcher.update_watchers(settings)
# no new warning
self.assertLogCountEqual(1, 'Watched path does not exist: .*static')
# get modified values
modified = watcher.check()
# empty theme and content should raise warnings
self.assertLogCountEqual(1, 'No valid files found in content')
self.assertLogCountEqual(1, 'Empty theme folder. Using `basic` theme')
self.assertIsNone(modified['content']) # empty
self.assertIsNone(modified['theme']) # empty
self.assertIsNone(modified['[static]static']) # empty
self.assertTrue(modified['settings']) # modified, first time
# add a content, add file to theme and check again
create_file(os.path.join(content_path, 'article.md'),
'Title: test\n'
'Date: 01-01-2020')
create_file(os.path.join(theme_path, 'dummy'),
'test')
modified = watcher.check()
# no new warning
self.assertLogCountEqual(1, 'No valid files found in content')
self.assertLogCountEqual(1, 'Empty theme folder. Using `basic` theme')
self.assertIsNone(modified['[static]static']) # empty
self.assertFalse(modified['settings']) # not modified
self.assertTrue(modified['theme']) # modified
self.assertTrue(modified['content']) # modified
# change config, remove static path
create_file(config_file,
'PATH = "content"\n'
'THEME = "mytheme"\n'
'STATIC_PATHS = []')
settings = read_settings(config_file)
watcher.update_watchers(settings)
modified = watcher.check()
self.assertNotIn('[static]static', modified) # should be gone
self.assertTrue(modified['settings']) # modified
self.assertFalse(modified['content']) # not modified
self.assertFalse(modified['theme']) # not modified
# cleanup
logger.enable_filter()
shutil.rmtree(root)
def test_clean_output_dir(self):
retention = ()
test_directory = os.path.join(self.temp_output,

View file

@ -24,6 +24,8 @@ except ModuleNotFoundError:
from backports.zoneinfo import ZoneInfo
from markupsafe import Markup
import watchfiles
logger = logging.getLogger(__name__)
@ -755,167 +757,31 @@ def order_content(content_list, order_by='slug'):
return content_list
class FileSystemWatcher:
def __init__(self, settings_file, reader_class, settings=None):
self.watchers = {
'settings': FileSystemWatcher.file_watcher(settings_file)
}
def wait_for_changes(settings_file, reader_class, settings):
new_extensions = set(reader_class(settings).extensions)
content_path = settings.get('PATH', '')
theme_path = settings.get('THEME', '')
ignore_files = set(settings.get('IGNORE_FILES', []))
self.settings = None
self.reader_class = reader_class
self._extensions = None
self._content_path = None
self._theme_path = None
self._ignore_files = None
watching_paths = [
settings_file,
theme_path,
content_path,
]
if settings is not None:
self.update_watchers(settings)
watching_paths.extend(
os.path.join(content_path, path) for path in settings.get('STATIC_PATHS', [])
)
def update_watchers(self, settings):
new_extensions = set(self.reader_class(settings).extensions)
new_content_path = settings.get('PATH', '')
new_theme_path = settings.get('THEME', '')
new_ignore_files = set(settings.get('IGNORE_FILES', []))
watching_paths = [os.path.abspath(p) for p in watching_paths if p and os.path.exists(p)]
extensions_changed = new_extensions != self._extensions
content_changed = new_content_path != self._content_path
theme_changed = new_theme_path != self._theme_path
ignore_changed = new_ignore_files != self._ignore_files
# Refresh content watcher if related settings changed
if extensions_changed or content_changed or ignore_changed:
self.add_watcher('content',
new_content_path,
new_extensions,
new_ignore_files)
# Refresh theme watcher if related settings changed
if theme_changed or ignore_changed:
self.add_watcher('theme',
new_theme_path,
[''],
new_ignore_files)
# Watch STATIC_PATHS
old_static_watchers = set(key
for key in self.watchers
if key.startswith('[static]'))
for path in settings.get('STATIC_PATHS', []):
key = '[static]{}'.format(path)
if ignore_changed or (key not in self.watchers):
self.add_watcher(
key,
os.path.join(new_content_path, path),
[''],
new_ignore_files)
if key in old_static_watchers:
old_static_watchers.remove(key)
# cleanup removed static watchers
for key in old_static_watchers:
del self.watchers[key]
# update values
self.settings = settings
self._extensions = new_extensions
self._content_path = new_content_path
self._theme_path = new_theme_path
self._ignore_files = new_ignore_files
def check(self):
'''return a key:watcher_status dict for all watchers'''
result = {key: next(watcher) for key, watcher in self.watchers.items()}
# Various warnings
if result.get('content') is None:
reader_descs = sorted(
{
' | %s (%s)' % (type(r).__name__, ', '.join(r.file_extensions))
for r in self.reader_class(self.settings).readers.values()
if r.enabled
}
)
logger.warning(
'No valid files found in content for the active readers:\n'
+ '\n'.join(reader_descs))
if result.get('theme') is None:
logger.warning('Empty theme folder. Using `basic` theme.')
return result
def add_watcher(self, key, path, extensions=[''], ignores=[]):
watcher = self.get_watcher(path, extensions, ignores)
if watcher is not None:
self.watchers[key] = watcher
def get_watcher(self, path, extensions=[''], ignores=[]):
'''return a watcher depending on path type (file or folder)'''
if not os.path.exists(path):
logger.warning("Watched path does not exist: %s", path)
return None
if os.path.isdir(path):
return self.folder_watcher(path, extensions, ignores)
else:
return self.file_watcher(path)
@staticmethod
def folder_watcher(path, extensions, ignores=[]):
'''Generator for monitoring a folder for modifications.
Returns a boolean indicating if files are changed since last check.
Returns None if there are no matching files in the folder'''
def file_times(path):
'''Return `mtime` for each file in path'''
for root, dirs, files in os.walk(path, followlinks=True):
dirs[:] = [x for x in dirs if not x.startswith(os.curdir)]
for f in files:
valid_extension = f.endswith(tuple(extensions))
file_ignored = any(
fnmatch.fnmatch(f, ignore) for ignore in ignores
)
if valid_extension and not file_ignored:
try:
yield os.stat(os.path.join(root, f)).st_mtime
except OSError as e:
logger.warning('Caught Exception: %s', e)
LAST_MTIME = 0
while True:
try:
mtime = max(file_times(path))
if mtime > LAST_MTIME:
LAST_MTIME = mtime
yield True
except ValueError:
yield None
else:
yield False
@staticmethod
def file_watcher(path):
'''Generator for monitoring a file for modifications'''
LAST_MTIME = 0
while True:
if path:
try:
mtime = os.stat(path).st_mtime
except OSError as e:
logger.warning('Caught Exception: %s', e)
continue
if mtime > LAST_MTIME:
LAST_MTIME = mtime
yield True
else:
yield False
else:
yield None
return next(watchfiles.watch(
*watching_paths,
watch_filter=watchfiles.DefaultFilter(
ignore_entity_patterns=[fnmatch.translate(pattern) for pattern in ignore_files]
),
rust_timeout=0
))
def set_date_tzinfo(d, tz_name=None):

View file

@ -41,6 +41,7 @@ rich = ">=10.1"
unidecode = ">=1.1"
markdown = {version = ">=3.1", optional = true}
backports-zoneinfo = {version = "^0.2.1", python = "<3.9"}
watchfiles = "^0.19.0"
[tool.poetry.dev-dependencies]
BeautifulSoup4 = "^4.9"