django1/django/utils/autoreload.py

275 lines
8.4 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 datetime
import os
import signal
import sys
import time
import traceback
from django.core.signals import request_finished
try:
from django.utils.six.moves import _thread as thread
except ImportError:
from django.utils.six.moves import _dummy_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
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
try:
import select
select.kevent, select.kqueue
USE_KQUEUE = True
import resource
NOFILES_SOFT, NOFILES_HARD = resource.getrlimit(resource.RLIMIT_NOFILE)
except AttributeError:
USE_KQUEUE = False
RUN_RELOADER = True
_mtimes = {}
_win = (sys.platform == "win32")
_error_files = []
def gen_filenames():
"""
Yields a generator over filenames referenced in sys.modules.
"""
filenames = [filename.__file__ for filename in sys.modules.values()
if hasattr(filename, '__file__')]
for filename in filenames + _error_files:
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):
yield filename
def inotify_code_changed():
"""
Checks for changed code using inotify. After being called
it blocks until a change event has been fired.
"""
wm = pyinotify.WatchManager()
notifier = pyinotify.Notifier(wm)
def update_watch(sender=None, **kwargs):
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():
wm.add_watch(path, mask)
request_finished.connect(update_watch)
update_watch()
# Block forever
notifier.check_events(timeout=None)
notifier.stop()
# If we are here the code must have changed.
return True
def kqueue_code_changed():
"""
Checks for changed code using kqueue. After being called
it blocks until a change event has been fired.
"""
# Maximum number of open file descriptors is typically too low (256).
filenames = list(gen_filenames())
resource.setrlimit(resource.RLIMIT_NOFILE,
(NOFILES_SOFT + len(filenames), NOFILES_HARD))
kqueue = select.kqueue()
fds = [open(filename) for filename in filenames]
_filter = select.KQ_FILTER_VNODE
flags = select.KQ_EV_ADD
fflags = select.KQ_NOTE_DELETE | select.KQ_NOTE_WRITE | select.KQ_NOTE_RENAME
kevents = [select.kevent(fd, _filter, flags, fflags) for fd in fds]
kqueue.control(kevents, 1)
for fd in fds:
fd.close()
kqueue.close()
return True
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 True
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
elif USE_KQUEUE:
fn = kqueue_code_changed
else:
fn = code_changed
while RUN_RELOADER:
if fn():
sys.exit(3) # force reload
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)