mirror of https://github.com/zulip/zulip.git
242 lines
8.7 KiB
Python
242 lines
8.7 KiB
Python
# Copyright 2009 Facebook
|
|
#
|
|
# 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.
|
|
|
|
"""Automatically restart the server when a source file is modified.
|
|
|
|
Most applications should not access this module directly. Instead,
|
|
pass the keyword argument ``autoreload=True`` to the
|
|
`tornado.web.Application` constructor (or ``debug=True``, which
|
|
enables this setting and several others). This will enable autoreload
|
|
mode as well as checking for changes to templates and static
|
|
resources. Note that restarting is a destructive operation and any
|
|
requests in progress will be aborted when the process restarts. (If
|
|
you want to disable autoreload while using other debug-mode features,
|
|
pass both ``debug=True`` and ``autoreload=False``).
|
|
|
|
This module can also be used as a command-line wrapper around scripts
|
|
such as unit test runners. See the `main` method for details.
|
|
|
|
The command-line wrapper and Application debug modes can be used together.
|
|
This combination is encouraged as the wrapper catches syntax errors and
|
|
other import-time failures, while debug mode catches changes once
|
|
the server has started.
|
|
|
|
This module depends on `.IOLoop`, so it will not work in WSGI applications
|
|
and Google App Engine. It also will not work correctly when `.HTTPServer`'s
|
|
multi-process mode is used.
|
|
|
|
Reloading loses any Python interpreter command-line arguments (e.g. ``-u``)
|
|
because it re-executes Python using ``sys.executable`` and ``sys.argv``.
|
|
Additionally, modifying these variables will cause reloading to behave
|
|
incorrectly.
|
|
|
|
"""
|
|
|
|
# Further patched by Zulip check whether the code we're about to
|
|
# reload actually imports before reloading into it. This fixes a
|
|
# major development workflow problem, where if one did a `git rebase`,
|
|
# Tornado would crash itself by auto-reloading into a version of the
|
|
# code that didn't work.
|
|
|
|
|
|
import os
|
|
import sys
|
|
import functools
|
|
import importlib
|
|
import traceback
|
|
import types
|
|
import subprocess
|
|
import weakref
|
|
|
|
from tornado import ioloop
|
|
from tornado.log import gen_log
|
|
from tornado import process
|
|
|
|
try:
|
|
import signal
|
|
except ImportError:
|
|
signal = None
|
|
|
|
# os.execv is broken on Windows and can't properly parse command line
|
|
# arguments and executable name if they contain whitespaces. subprocess
|
|
# fixes that behavior.
|
|
_has_execv = sys.platform != 'win32'
|
|
|
|
_watched_files = set()
|
|
_reload_hooks = []
|
|
_reload_attempted = False
|
|
_io_loops = weakref.WeakKeyDictionary() # type: ignore # upstream
|
|
needs_to_reload = False
|
|
|
|
def start(io_loop=None, check_time=500):
|
|
"""Begins watching source files for changes.
|
|
|
|
.. versionchanged:: 4.1
|
|
The ``io_loop`` argument is deprecated.
|
|
"""
|
|
io_loop = io_loop or ioloop.IOLoop.current()
|
|
if io_loop in _io_loops:
|
|
return
|
|
_io_loops[io_loop] = True
|
|
if len(_io_loops) > 1:
|
|
gen_log.warning("tornado.autoreload started more than once in the same process")
|
|
modify_times = {}
|
|
callback = functools.partial(_reload_on_update, modify_times)
|
|
scheduler = ioloop.PeriodicCallback(callback, check_time, io_loop=io_loop)
|
|
scheduler.start()
|
|
|
|
|
|
def wait():
|
|
"""Wait for a watched file to change, then restart the process.
|
|
|
|
Intended to be used at the end of scripts like unit test runners,
|
|
to run the tests again after any source file changes (but see also
|
|
the command-line interface in `main`)
|
|
"""
|
|
io_loop = ioloop.IOLoop()
|
|
start(io_loop)
|
|
io_loop.start()
|
|
|
|
|
|
def watch(filename):
|
|
"""Add a file to the watch list.
|
|
|
|
All imported modules are watched by default.
|
|
"""
|
|
_watched_files.add(filename)
|
|
|
|
|
|
def add_reload_hook(fn):
|
|
"""Add a function to be called before reloading the process.
|
|
|
|
Note that for open file and socket handles it is generally
|
|
preferable to set the ``FD_CLOEXEC`` flag (using `fcntl` or
|
|
``tornado.platform.auto.set_close_exec``) instead
|
|
of using a reload hook to close them.
|
|
"""
|
|
_reload_hooks.append(fn)
|
|
|
|
|
|
def _reload_on_update(modify_times):
|
|
global needs_to_reload
|
|
if _reload_attempted:
|
|
# We already tried to reload and it didn't work, so don't try again.
|
|
return
|
|
if process.task_id() is not None:
|
|
# We're in a child process created by fork_processes. If child
|
|
# processes restarted themselves, they'd all restart and then
|
|
# all call fork_processes again.
|
|
return
|
|
for module in list(sys.modules.values()):
|
|
# Some modules play games with sys.modules (e.g. email/__init__.py
|
|
# in the standard library), and occasionally this can cause strange
|
|
# failures in getattr. Just ignore anything that's not an ordinary
|
|
# module.
|
|
if not isinstance(module, types.ModuleType):
|
|
continue
|
|
path = getattr(module, "__file__", None)
|
|
if not path:
|
|
continue
|
|
if path.endswith(".pyc") or path.endswith(".pyo"):
|
|
path = path[:-1]
|
|
|
|
result = _check_file(modify_times, module, path)
|
|
if result is False:
|
|
# If any files errored, we abort this attempt at reloading.
|
|
return
|
|
if result is True:
|
|
# If any files had actual changes that import properly,
|
|
# we'll plan to reload the next time we run with no files
|
|
# erroring.
|
|
needs_to_reload = True
|
|
|
|
if needs_to_reload:
|
|
_reload()
|
|
|
|
|
|
def _check_file(modify_times, module, path):
|
|
try:
|
|
modified = os.stat(path).st_mtime
|
|
except Exception:
|
|
return
|
|
if path not in modify_times:
|
|
modify_times[path] = modified
|
|
return
|
|
if modify_times[path] != modified:
|
|
gen_log.info("%s modified; restarting server", path)
|
|
modify_times[path] = modified
|
|
else:
|
|
return
|
|
|
|
if path == __file__ or path == os.path.join(os.path.dirname(__file__),
|
|
"event_queue.py"):
|
|
# Assume that the autoreload library itself imports correctly,
|
|
# because reloading this file will destroy its state,
|
|
# including _reload_hooks
|
|
return True
|
|
|
|
try:
|
|
importlib.reload(module)
|
|
except Exception:
|
|
gen_log.error("Error importing %s, not reloading" % (path,))
|
|
traceback.print_exc()
|
|
return False
|
|
return True
|
|
|
|
def _reload():
|
|
global _reload_attempted
|
|
_reload_attempted = True
|
|
for fn in _reload_hooks:
|
|
fn()
|
|
# Make sure any output from reload hooks makes it to stdout.
|
|
sys.stdout.flush()
|
|
if hasattr(signal, "setitimer"):
|
|
# Clear the alarm signal set by
|
|
# ioloop.set_blocking_log_threshold so it doesn't fire
|
|
# after the exec.
|
|
signal.setitimer(signal.ITIMER_REAL, 0, 0)
|
|
# sys.path fixes: see comments at top of file. If sys.path[0] is an empty
|
|
# string, we were (probably) invoked with -m and the effective path
|
|
# is about to change on re-exec. Add the current directory to $PYTHONPATH
|
|
# to ensure that the new process sees the same path we did.
|
|
path_prefix = '.' + os.pathsep
|
|
if (sys.path[0] == '' and
|
|
not os.environ.get("PYTHONPATH", "").startswith(path_prefix)):
|
|
os.environ["PYTHONPATH"] = (path_prefix +
|
|
os.environ.get("PYTHONPATH", ""))
|
|
if not _has_execv:
|
|
subprocess.Popen([sys.executable] + sys.argv)
|
|
sys.exit(0)
|
|
else:
|
|
try:
|
|
os.execv(sys.executable, [sys.executable] + sys.argv)
|
|
except OSError:
|
|
# Mac OS X versions prior to 10.6 do not support execv in
|
|
# a process that contains multiple threads. Instead of
|
|
# re-executing in the current process, start a new one
|
|
# and cause the current process to exit. This isn't
|
|
# ideal since the new process is detached from the parent
|
|
# terminal and thus cannot easily be killed with ctrl-C,
|
|
# but it's better than not being able to autoreload at
|
|
# all.
|
|
# Unfortunately the errno returned in this case does not
|
|
# appear to be consistent, so we can't easily check for
|
|
# this error specifically.
|
|
os.spawnv(os.P_NOWAIT, sys.executable,
|
|
[sys.executable] + sys.argv)
|
|
# At this point the IOLoop has been closed and finally
|
|
# blocks will experience errors if we allow the stack to
|
|
# unwind, so just exit uncleanly.
|
|
os._exit(0)
|