django1/django/utils/autoreload.py

321 lines
10 KiB
Python

# Autoreloading launcher.
# Borrowed from Peter Hunt and the CherryPy project (http://www.cherrypy.org).
# Some taken from Ian Bicking's Paste (http://pythonpaste.org/).
#
# Portions copyright (c) 2004, CherryPy Team (team@cherrypy.org)
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice,
# this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
# * Neither the name of the CherryPy Team nor the names of its contributors
# may be used to endorse or promote products derived from this software
# without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
import os
import signal
import sys
import time
import traceback
from django.apps import apps
from django.conf import settings
from django.core.signals import request_finished
from django.utils.six.moves import _thread as thread
# This import does nothing, but it's necessary to avoid some race conditions
# in the threading module. See http://code.djangoproject.com/ticket/2330 .
try:
import threading # NOQA
except ImportError:
pass
try:
import termios
except ImportError:
termios = None
USE_INOTIFY = False
try:
# Test whether inotify is enabled and likely to work
import pyinotify
fd = pyinotify.INotifyWrapper.create().inotify_init()
if fd >= 0:
USE_INOTIFY = True
os.close(fd)
except ImportError:
pass
RUN_RELOADER = True
FILE_MODIFIED = 1
I18N_MODIFIED = 2
_mtimes = {}
_win = (sys.platform == "win32")
_error_files = []
_cached_modules = set()
_cached_filenames = []
def gen_filenames(only_new=False):
"""
Returns a list of filenames referenced in sys.modules and translation
files.
"""
# N.B. ``list(...)`` is needed, because this runs in parallel with
# application code which might be mutating ``sys.modules``, and this will
# fail with RuntimeError: cannot mutate dictionary while iterating
global _cached_modules, _cached_filenames
module_values = set(sys.modules.values())
_cached_filenames = clean_files(_cached_filenames)
if _cached_modules == module_values:
# No changes in module list, short-circuit the function
if only_new:
return []
else:
return _cached_filenames
new_modules = module_values - _cached_modules
new_filenames = clean_files(
[filename.__file__ for filename in new_modules
if hasattr(filename, '__file__')])
if not _cached_filenames and settings.USE_I18N:
# Add the names of the .mo files that can be generated
# by compilemessages management command to the list of files watched.
basedirs = [os.path.join(os.path.dirname(os.path.dirname(__file__)),
'conf', 'locale'),
'locale']
for app_config in reversed(list(apps.get_app_configs())):
basedirs.append(os.path.join(app_config.path, 'locale'))
basedirs.extend(settings.LOCALE_PATHS)
basedirs = [os.path.abspath(basedir) for basedir in basedirs
if os.path.isdir(basedir)]
for basedir in basedirs:
for dirpath, dirnames, locale_filenames in os.walk(basedir):
for filename in locale_filenames:
if filename.endswith('.mo'):
new_filenames.append(os.path.join(dirpath, filename))
_cached_modules = _cached_modules.union(new_modules)
_cached_filenames += new_filenames
if only_new:
return new_filenames
else:
return _cached_filenames + clean_files(_error_files)
def clean_files(filelist):
filenames = []
for filename in filelist:
if not filename:
continue
if filename.endswith(".pyc") or filename.endswith(".pyo"):
filename = filename[:-1]
if filename.endswith("$py.class"):
filename = filename[:-9] + ".py"
if os.path.exists(filename):
filenames.append(filename)
return filenames
def reset_translations():
import gettext
from django.utils.translation import trans_real
gettext._translations = {}
trans_real._translations = {}
trans_real._default = None
trans_real._active = threading.local()
def inotify_code_changed():
"""
Checks for changed code using inotify. After being called
it blocks until a change event has been fired.
"""
class EventHandler(pyinotify.ProcessEvent):
modified_code = None
def process_default(self, event):
if event.path.endswith('.mo'):
EventHandler.modified_code = I18N_MODIFIED
else:
EventHandler.modified_code = FILE_MODIFIED
wm = pyinotify.WatchManager()
notifier = pyinotify.Notifier(wm, EventHandler())
def update_watch(sender=None, **kwargs):
if sender and getattr(sender, 'handles_files', False):
# No need to update watches when request serves files.
# (sender is supposed to be a django.core.handlers.BaseHandler subclass)
return
mask = (
pyinotify.IN_MODIFY |
pyinotify.IN_DELETE |
pyinotify.IN_ATTRIB |
pyinotify.IN_MOVED_FROM |
pyinotify.IN_MOVED_TO |
pyinotify.IN_CREATE
)
for path in gen_filenames(only_new=True):
wm.add_watch(path, mask)
# New modules may get imported when a request is processed.
request_finished.connect(update_watch)
# Block until an event happens.
update_watch()
notifier.check_events(timeout=None)
notifier.read_events()
notifier.process_events()
notifier.stop()
# If we are here the code must have changed.
return EventHandler.modified_code
def code_changed():
global _mtimes, _win
for filename in gen_filenames():
stat = os.stat(filename)
mtime = stat.st_mtime
if _win:
mtime -= stat.st_ctime
if filename not in _mtimes:
_mtimes[filename] = mtime
continue
if mtime != _mtimes[filename]:
_mtimes = {}
try:
del _error_files[_error_files.index(filename)]
except ValueError:
pass
return I18N_MODIFIED if filename.endswith('.mo') else FILE_MODIFIED
return False
def check_errors(fn):
def wrapper(*args, **kwargs):
try:
fn(*args, **kwargs)
except (ImportError, IndentationError, NameError, SyntaxError,
TypeError, AttributeError):
et, ev, tb = sys.exc_info()
if getattr(ev, 'filename', None) is None:
# get the filename from the last item in the stack
filename = traceback.extract_tb(tb)[-1][0]
else:
filename = ev.filename
if filename not in _error_files:
_error_files.append(filename)
raise
return wrapper
def ensure_echo_on():
if termios:
fd = sys.stdin
if fd.isatty():
attr_list = termios.tcgetattr(fd)
if not attr_list[3] & termios.ECHO:
attr_list[3] |= termios.ECHO
if hasattr(signal, 'SIGTTOU'):
old_handler = signal.signal(signal.SIGTTOU, signal.SIG_IGN)
else:
old_handler = None
termios.tcsetattr(fd, termios.TCSANOW, attr_list)
if old_handler is not None:
signal.signal(signal.SIGTTOU, old_handler)
def reloader_thread():
ensure_echo_on()
if USE_INOTIFY:
fn = inotify_code_changed
else:
fn = code_changed
while RUN_RELOADER:
change = fn()
if change == FILE_MODIFIED:
sys.exit(3) # force reload
elif change == I18N_MODIFIED:
reset_translations()
time.sleep(1)
def restart_with_reloader():
while True:
args = [sys.executable] + ['-W%s' % o for o in sys.warnoptions] + sys.argv
if sys.platform == "win32":
args = ['"%s"' % arg for arg in args]
new_environ = os.environ.copy()
new_environ["RUN_MAIN"] = 'true'
exit_code = os.spawnve(os.P_WAIT, sys.executable, args, new_environ)
if exit_code != 3:
return exit_code
def python_reloader(main_func, args, kwargs):
if os.environ.get("RUN_MAIN") == "true":
thread.start_new_thread(main_func, args, kwargs)
try:
reloader_thread()
except KeyboardInterrupt:
pass
else:
try:
exit_code = restart_with_reloader()
if exit_code < 0:
os.kill(os.getpid(), -exit_code)
else:
sys.exit(exit_code)
except KeyboardInterrupt:
pass
def jython_reloader(main_func, args, kwargs):
from _systemrestart import SystemRestart
thread.start_new_thread(main_func, args)
while True:
if code_changed():
raise SystemRestart
time.sleep(1)
def main(main_func, args=None, kwargs=None):
if args is None:
args = ()
if kwargs is None:
kwargs = {}
if sys.platform.startswith('java'):
reloader = jython_reloader
else:
reloader = python_reloader
wrapped_main_func = check_errors(main_func)
reloader(wrapped_main_func, args, kwargs)