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mitogen/mitogen/master.py

1036 lines
32 KiB
Python

import dis
import errno
import getpass
import imp
import inspect
import itertools
import logging
import os
import pkgutil
import pty
import re
import select
import signal
import socket
import sys
import termios
import textwrap
import threading
import time
import types
import zlib
try:
import Queue
except ImportError:
import queue as Queue
if not hasattr(pkgutil, 'find_loader'):
# find_loader() was new in >=2.5, but the modern pkgutil.py syntax has
# been kept intentionally 2.3 compatible so we can reuse it.
from mitogen.compat import pkgutil
import mitogen.core
LOG = logging.getLogger('mitogen')
IOLOG = logging.getLogger('mitogen.io')
RLOG = logging.getLogger('mitogen.ctx')
DOCSTRING_RE = re.compile(r'""".+?"""', re.M | re.S)
COMMENT_RE = re.compile(r'^[ ]*#[^\n]*$', re.M)
IOLOG_RE = re.compile(r'^[ ]*IOLOG.debug\(.+?\)$', re.M)
def minimize_source(source):
subber = lambda match: '""' + ('\n' * match.group(0).count('\n'))
source = DOCSTRING_RE.sub(subber, source)
source = COMMENT_RE.sub('', source)
return source.replace(' ', '\t')
def get_child_modules(path, fullname):
it = pkgutil.iter_modules([os.path.dirname(path)])
return ['%s.%s' % (fullname, name) for _, name, _ in it]
class Argv(object):
def __init__(self, argv):
self.argv = argv
def escape(self, x):
s = '"'
for c in x:
if c in '\\$"`':
s += '\\'
s += c
s += '"'
return s
def __str__(self):
return ' '.join(map(self.escape, self.argv))
def create_child(*args):
parentfp, childfp = socket.socketpair()
pid = os.fork()
if not pid:
os.dup2(childfp.fileno(), 0)
os.dup2(childfp.fileno(), 1)
childfp.close()
parentfp.close()
os.execvp(args[0], args)
raise SystemExit
childfp.close()
LOG.debug('create_child() child %d fd %d, parent %d, cmd: %s',
pid, parentfp.fileno(), os.getpid(), Argv(args))
return pid, os.dup(parentfp.fileno())
def flags(names):
"""Return the result of ORing a set of (space separated) :py:mod:`termios`
module constants together."""
return sum(getattr(termios, name) for name in names.split())
def cfmakeraw(tflags):
"""Given a list returned by :py:func:`termios.tcgetattr`, return a list
that has been modified in the same manner as the `cfmakeraw()` C library
function."""
iflag, oflag, cflag, lflag, ispeed, ospeed, cc = tflags
iflag &= ~flags('IGNBRK BRKINT PARMRK ISTRIP INLCR IGNCR ICRNL IXON')
oflag &= ~flags('OPOST IXOFF')
lflag &= ~flags('ECHO ECHOE ECHONL ICANON ISIG IEXTEN')
cflag &= ~flags('CSIZE PARENB')
cflag |= flags('CS8')
iflag = 0
oflag = 0
lflag = 0
return [iflag, oflag, cflag, lflag, ispeed, ospeed, cc]
def disable_echo(fd):
old = termios.tcgetattr(fd)
new = cfmakeraw(old)
flags = (
termios.TCSAFLUSH |
getattr(termios, 'TCSASOFT', 0)
)
termios.tcsetattr(fd, flags, new)
def close_nonstandard_fds():
for fd in xrange(3, 1024):
try:
os.close(fd)
except OSError:
pass
def tty_create_child(*args):
master_fd, slave_fd = os.openpty()
disable_echo(master_fd)
disable_echo(slave_fd)
pid = os.fork()
if not pid:
os.dup2(slave_fd, 0)
os.dup2(slave_fd, 1)
os.dup2(slave_fd, 2)
close_nonstandard_fds()
os.setsid()
os.close(os.open(os.ttyname(1), os.O_RDWR))
os.execvp(args[0], args)
raise SystemExit
os.close(slave_fd)
LOG.debug('tty_create_child() child %d fd %d, parent %d, cmd: %s',
pid, master_fd, os.getpid(), Argv(args))
return pid, master_fd
def write_all(fd, s, deadline=None):
timeout = None
written = 0
while written < len(s):
if deadline is not None:
timeout = max(0, deadline - time.time())
if timeout == 0:
raise mitogen.core.TimeoutError('write timed out')
_, wfds, _ = select.select([], [fd], [], timeout)
if not wfds:
continue
n, disconnected = mitogen.core.io_op(os.write, fd, buffer(s, written))
if disconnected:
raise mitogen.core.StreamError('EOF on stream during write')
written += n
def iter_read(fd, deadline=None):
bits = []
timeout = None
while True:
if deadline is not None:
timeout = max(0, deadline - time.time())
if timeout == 0:
break
rfds, _, _ = select.select([fd], [], [], timeout)
if not rfds:
continue
s, disconnected = mitogen.core.io_op(os.read, fd, 4096)
IOLOG.debug('iter_read(%r) -> %r', fd, s)
if disconnected or not s:
raise mitogen.core.StreamError(
'EOF on stream; last 300 bytes received: %r' %
(''.join(bits)[-300:],)
)
bits.append(s)
yield s
raise mitogen.core.TimeoutError('read timed out')
def discard_until(fd, s, deadline):
for buf in iter_read(fd, deadline):
if buf.endswith(s):
return
def scan_code_imports(co, LOAD_CONST=dis.opname.index('LOAD_CONST'),
IMPORT_NAME=dis.opname.index('IMPORT_NAME')):
"""Given a code object `co`, scan its bytecode yielding any
``IMPORT_NAME`` and associated prior ``LOAD_CONST`` instructions
representing an `Import` statement or `ImportFrom` statement.
:return:
Generator producing `(level, modname, namelist)` tuples, where:
* `level`: -1 for normal import, 0, for absolute import, and >0 for
relative import.
* `modname`: Name of module to import, or from where `namelist` names
are imported.
* `namelist`: for `ImportFrom`, the list of names to be imported from
`modname`.
"""
# Yield `(op, oparg)` tuples from the code object `co`.
ordit = itertools.imap(ord, co.co_code)
nextb = ordit.next
opit = ((c, (None
if c < dis.HAVE_ARGUMENT else
(nextb() | (nextb() << 8))))
for c in ordit)
opit, opit2, opit3 = itertools.tee(opit, 3)
next(opit2)
next(opit3)
next(opit3)
for oparg1, oparg2, (op3, arg3) in itertools.izip(opit, opit2, opit3):
if op3 == IMPORT_NAME:
op2, arg2 = oparg2
op1, arg1 = oparg1
if op1 == op2 == LOAD_CONST:
yield (co.co_consts[arg1],
co.co_names[arg3],
co.co_consts[arg2] or ())
class SelectError(mitogen.core.Error):
pass
class Select(object):
notify = None
def __init__(self, receivers=(), oneshot=True):
self._receivers = []
self._oneshot = oneshot
self._queue = Queue.Queue()
for recv in receivers:
self.add(recv)
def _put(self, value):
self._queue.put(value)
if self.notify:
self.notify(self)
def __bool__(self):
return bool(self._receivers)
def __enter__(self):
return self
def __exit__(self, e_type, e_val, e_tb):
self.close()
def __iter__(self):
while self._receivers:
recv, msg = self.get()
yield recv, msg
loop_msg = 'Adding this Select instance would create a Select cycle'
def _check_no_loop(self, recv):
if recv is self:
raise SelectError(self.loop_msg)
for recv_ in self._receivers:
if recv_ == recv:
raise SelectError(self.loop_msg)
if isinstance(recv_, Select):
recv_._check_no_loop(recv)
owned_msg = 'Cannot add: Receiver is already owned by another Select'
def add(self, recv):
if isinstance(recv, Select):
recv._check_no_loop(self)
self._receivers.append(recv)
if recv.notify is not None:
raise SelectError(self.owned_msg)
recv.notify = self._put
# Avoid race by polling once after installation.
if not recv.empty():
self._put(recv)
not_present_msg = 'Instance is not a member of this Select'
def remove(self, recv):
try:
if recv.notify != self._put:
raise ValueError
self._receivers.remove(recv)
recv.notify = None
except (IndexError, ValueError):
raise SelectError(self.not_present_msg)
def close(self):
for recv in self._receivers[:]:
self.remove(recv)
def empty(self):
return self._queue.empty()
empty_msg = 'Cannot get(), Select instance is empty'
def get(self, timeout=None):
if not self._receivers:
raise SelectError(self.empty_msg)
while True:
recv = mitogen.core._queue_interruptible_get(self._queue, timeout)
try:
msg = recv.get(block=False)
if self._oneshot:
self.remove(recv)
return recv, msg
except mitogen.core.TimeoutError:
# A receiver may have been queued with no result if another
# thread drained it before we woke up, or because another
# thread drained it between add() calling recv.empty() and
# self._put(). In this case just sleep again.
continue
class LogForwarder(object):
def __init__(self, router):
self._router = router
self._cache = {}
router.add_handler(self._on_forward_log, mitogen.core.FORWARD_LOG)
def _on_forward_log(self, msg):
if msg == mitogen.core._DEAD:
return
logger = self._cache.get(msg.src_id)
if logger is None:
context = self._router.context_by_id(msg.src_id)
if context is None:
LOG.error('FORWARD_LOG received from src_id %d', msg.src_id)
return
name = '%s.%s' % (RLOG.name, context.name)
self._cache[msg.src_id] = logger = logging.getLogger(name)
name, level_s, s = msg.data.split('\x00', 2)
logger.log(int(level_s), '%s: %s', name, s)
def __repr__(self):
return 'LogForwarder(%r)' % (self._router,)
class ModuleFinder(object):
STDLIB_DIRS = [
# virtualenv on OS X does some weird half-ass job of symlinking the
# stdlib into the virtualenv directory. So pick two modules at random
# that represent both places the stdlib seems to come from.
os.path.dirname(os.path.dirname(logging.__file__)),
os.path.dirname(os.path.dirname(os.__file__)),
]
def __init__(self):
#: Import machinery is expensive, keep :py:meth`:get_module_source`
#: results around.
self._found_cache = {}
#: Avoid repeated dependency scanning, which is expensive.
self._related_cache = {}
def __repr__(self):
return 'ModuleFinder()'
def is_stdlib_name(self, modname):
"""Return ``True`` if `modname` appears to come from the standard
library."""
if imp.is_builtin(modname) != 0:
return True
module = sys.modules.get(modname)
if module is None:
return False
# six installs crap with no __file__
modpath = getattr(module, '__file__', '')
if 'site-packages' in modpath:
return False
for dirname in self.STDLIB_DIRS:
if os.path.commonprefix((dirname, modpath)) == dirname:
return True
return False
def _py_filename(self, path):
path = path.rstrip('co')
if path.endswith('.py'):
return path
def _get_module_via_pkgutil(self, fullname):
"""Attempt to fetch source code via pkgutil. In an ideal world, this
would be the only required implementation of get_module()."""
loader = pkgutil.find_loader(fullname)
LOG.debug('pkgutil._get_module_via_pkgutil(%r) -> %r', fullname, loader)
if not loader:
return
try:
path = self._py_filename(loader.get_filename(fullname))
source = loader.get_source(fullname)
if path is not None and source is not None:
return path, source, loader.is_package(fullname)
except AttributeError:
return
def _get_module_via_sys_modules(self, fullname):
"""Attempt to fetch source code via sys.modules. This is specifically
to support __main__, but it may catch a few more cases."""
module = sys.modules.get(fullname)
if not isinstance(module, types.ModuleType):
LOG.debug('sys.modules[%r] absent or not a regular module',
fullname)
return
modpath = self._py_filename(getattr(module, '__file__', ''))
if not modpath:
return
is_pkg = hasattr(module, '__path__')
try:
source = inspect.getsource(module)
except IOError:
# Work around inspect.getsourcelines() bug.
if not is_pkg:
raise
source = '\n'
return (module.__file__.rstrip('co'),
source,
hasattr(module, '__path__'))
get_module_methods = [_get_module_via_pkgutil,
_get_module_via_sys_modules]
def get_module_source(self, fullname):
"""Given the name of a loaded module `fullname`, attempt to find its
source code.
:returns:
Tuple of `(module path, source text, is package?)`, or ``None`` if
the source cannot be found.
"""
tup = self._found_cache.get(fullname)
if tup:
return tup
for method in self.get_module_methods:
tup = method(self, fullname)
if tup:
return tup
return None, None, None
def resolve_relpath(self, fullname, level):
"""Given an ImportFrom AST node, guess the prefix that should be tacked
on to an alias name to produce a canonical name. `fullname` is the name
of the module in which the ImportFrom appears."""
if level == 0 or not fullname:
return ''
bits = fullname.split('.')
if len(bits) <= level:
# This would be an ImportError in real code.
return ''
return '.'.join(bits[:-level]) + '.'
def generate_parent_names(self, fullname):
while '.' in fullname:
fullname = fullname[:fullname.rindex('.')]
yield fullname
def find_related_imports(self, fullname):
"""
Given the `fullname` of a currently loaded module, and a copy of its
source code, examine :py:data:`sys.modules` to determine which of the
``import`` statements from the source code caused a corresponding
module to be loaded that is not part of the standard library.
"""
related = self._related_cache.get(fullname)
if related is not None:
return related
modpath, src, _ = self.get_module_source(fullname)
if src is None:
LOG.warning('%r: cannot find source for %r', self, fullname)
return []
maybe_names = list(self.generate_parent_names(fullname))
co = compile(src, modpath, 'exec')
for level, modname, namelist in scan_code_imports(co):
if level == -1:
modnames = [modname, '%s.%s' % (fullname, modname)]
else:
modnames = [self.resolve_relpath(fullname, level) + modname]
maybe_names.extend(modnames)
maybe_names.extend(
'%s.%s' % (mname, name)
for mname in modnames
for name in namelist
)
return self._related_cache.setdefault(fullname, sorted(
set(
name
for name in maybe_names
if sys.modules.get(name) is not None
and not self.is_stdlib_name(name)
and 'six.moves' not in name # TODO: crap
)
))
def find_related(self, fullname):
stack = [fullname]
found = set()
while stack:
fullname = stack.pop(0)
fullnames = self.find_related_imports(fullname)
stack.extend(set(fullnames).difference(found, stack, [fullname]))
found.update(fullnames)
return found
class ModuleResponder(object):
def __init__(self, router):
self._router = router
self._finder = ModuleFinder()
router.add_handler(self._on_get_module, mitogen.core.GET_MODULE)
def __repr__(self):
return 'ModuleResponder(%r)' % (self._router,)
MAIN_RE = re.compile(r'^if\s+__name__\s*==\s*.__main__.\s*:', re.M)
def neutralize_main(self, src):
"""Given the source for the __main__ module, try to find where it
begins conditional execution based on a "if __name__ == '__main__'"
guard, and remove any code after that point."""
match = self.MAIN_RE.search(src)
if match:
return src[:match.start()]
return src
def _on_get_module(self, msg):
LOG.debug('%r.get_module(%r)', self, msg)
if msg == mitogen.core._DEAD:
return
fullname = msg.data
try:
path, source, is_pkg = self._finder.get_module_source(fullname)
if source is None:
raise ImportError('could not find %r' % (fullname,))
if is_pkg:
pkg_present = get_child_modules(path, fullname)
LOG.debug('get_child_modules(%r, %r) -> %r',
path, fullname, pkg_present)
else:
pkg_present = None
if fullname == '__main__':
source = self.neutralize_main(source)
compressed = zlib.compress(source)
related = list(self._finder.find_related(fullname))
self._router.route(
mitogen.core.Message.pickled(
(pkg_present, path, compressed, related),
dst_id=msg.src_id,
handle=msg.reply_to,
)
)
except Exception:
LOG.debug('While importing %r', fullname, exc_info=True)
self._router.route(
mitogen.core.Message.pickled(
None,
dst_id=msg.src_id,
handle=msg.reply_to,
)
)
class ModuleForwarder(object):
"""
Respond to GET_MODULE requests in a slave by forwarding the request to our
parent context, or satisfying the request from our local Importer cache.
"""
def __init__(self, router, parent_context, importer):
self.router = router
self.parent_context = parent_context
self.importer = importer
router.add_handler(self._on_get_module, mitogen.core.GET_MODULE)
def __repr__(self):
return 'ModuleForwarder(%r)' % (self.router,)
def _on_get_module(self, msg):
LOG.debug('%r._on_get_module(%r)', self, msg)
if msg == mitogen.core._DEAD:
return
fullname = msg.data
cached = self.importer._cache.get(fullname)
if cached:
LOG.debug('%r._on_get_module(): using cached %r', self, fullname)
self.router.route(
mitogen.core.Message.pickled(
cached,
dst_id=msg.src_id,
handle=msg.reply_to,
)
)
else:
LOG.debug('%r._on_get_module(): requesting %r', self, fullname)
self.parent_context.send(
mitogen.core.Message(
data=msg.data,
handle=mitogen.core.GET_MODULE,
reply_to=self.router.add_handler(
lambda m: self._on_got_source(m, msg),
persist=False
)
)
)
def _on_got_source(self, msg, original_msg):
LOG.debug('%r._on_got_source(%r, %r)', self, msg, original_msg)
fullname = original_msg.data
self.importer._cache[fullname] = msg.unpickle()
self.router.route(
mitogen.core.Message(
data=msg.data,
dst_id=original_msg.src_id,
handle=original_msg.reply_to,
)
)
class Stream(mitogen.core.Stream):
"""
Base for streams capable of starting new slaves.
"""
#: The path to the remote Python interpreter.
python_path = 'python2.7'
#: True to cause context to write verbose /tmp/mitogen.<pid>.log.
debug = False
#: True to cause context to write /tmp/mitogen.stats.<pid>.<thread>.log.
profiling = False
def construct(self, remote_name=None, python_path=None, debug=False,
profiling=False, **kwargs):
"""Get the named context running on the local machine, creating it if
it does not exist."""
super(Stream, self).construct(**kwargs)
if python_path:
self.python_path = python_path
if remote_name is None:
remote_name = '%s@%s:%d'
remote_name %= (getpass.getuser(), socket.gethostname(), os.getpid())
self.remote_name = remote_name
self.debug = debug
self.profiling = profiling
def on_shutdown(self, broker):
"""Request the slave gracefully shut itself down."""
LOG.debug('%r closing CALL_FUNCTION channel', self)
self.send(
mitogen.core.Message(
src_id=mitogen.context_id,
dst_id=self.remote_id,
handle=mitogen.core.SHUTDOWN,
)
)
# base64'd and passed to 'python -c'. It forks, dups 0->100, creates a
# pipe, then execs a new interpreter with a custom argv. 'CONTEXT_NAME' is
# replaced with the context name. Optimized for size.
@staticmethod
def _first_stage():
import os,sys,zlib
R,W=os.pipe()
r,w=os.pipe()
if os.fork():
os.dup2(0,100)
os.dup2(R,0)
os.dup2(r,101)
for f in R,r,W,w:os.close(f)
os.environ['ARGV0']=e=sys.executable
os.execv(e,['mitogen:CONTEXT_NAME'])
os.write(1,'EC0\n')
C=zlib.decompress(sys.stdin.read(input()))
os.fdopen(W,'w',0).write(C)
os.fdopen(w,'w',0).write('%s\n'%len(C)+C)
os.write(1,'EC1\n')
sys.exit(0)
def get_boot_command(self):
source = inspect.getsource(self._first_stage)
source = textwrap.dedent('\n'.join(source.strip().split('\n')[2:]))
source = source.replace(' ', '\t')
source = source.replace('CONTEXT_NAME', self.remote_name)
encoded = source.encode('zlib').encode('base64').replace('\n', '')
# We can't use bytes.decode() in 3.x since it was restricted to always
# return unicode, so codecs.decode() is used instead. In 3.x
# codecs.decode() requires a bytes object. Since we must be compatible
# with 2.4 (no bytes literal), an extra .encode() either returns the
# same str (2.x) or an equivalent bytes (3.x).
return [
self.python_path, '-c',
'from codecs import decode as _;'
'exec(_(_("%s".encode(),"base64"),"zlib"))' % (encoded,)
]
def get_preamble(self):
parent_ids = mitogen.parent_ids[:]
parent_ids.insert(0, mitogen.context_id)
source = inspect.getsource(mitogen.core)
source += '\nExternalContext().main%r\n' % ((
parent_ids, # parent_ids
self.remote_id, # context_id
self.debug,
self.profiling,
LOG.level or logging.getLogger().level or logging.INFO,
),)
compressed = zlib.compress(minimize_source(source))
return str(len(compressed)) + '\n' + compressed
create_child = staticmethod(create_child)
def connect(self):
LOG.debug('%r.connect()', self)
pid, fd = self.create_child(*self.get_boot_command())
self.name = 'local.%s' % (pid,)
self.receive_side = mitogen.core.Side(self, fd)
self.transmit_side = mitogen.core.Side(self, os.dup(fd))
LOG.debug('%r.connect(): child process stdin/stdout=%r',
self, self.receive_side.fd)
self._connect_bootstrap()
def _ec0_received(self):
LOG.debug('%r._ec0_received()', self)
write_all(self.transmit_side.fd, self.get_preamble())
discard_until(self.receive_side.fd, 'EC1\n', time.time() + 10.0)
def _connect_bootstrap(self):
discard_until(self.receive_side.fd, 'EC0\n', time.time() + 10.0)
self._ec0_received()
class Broker(mitogen.core.Broker):
shutdown_timeout = 5.0
class Context(mitogen.core.Context):
via = None
def on_disconnect(self, broker):
"""
Override base behaviour of triggering Broker shutdown on parent stream
disconnection.
"""
mitogen.core.fire(self, 'disconnect')
def call_async(self, fn, *args, **kwargs):
LOG.debug('%r.call_async(%r, *%r, **%r)',
self, fn, args, kwargs)
if isinstance(fn, types.MethodType) and \
isinstance(fn.im_self, (type, types.ClassType)):
klass = fn.im_self.__name__
else:
klass = None
recv = self.send_async(
mitogen.core.Message.pickled(
(fn.__module__, klass, fn.__name__, args, kwargs),
handle=mitogen.core.CALL_FUNCTION,
)
)
recv.raise_channelerror = False
return recv
def call(self, fn, *args, **kwargs):
return self.call_async(fn, *args, **kwargs).get_data()
def _local_method():
return Stream
def _ssh_method():
import mitogen.ssh
return mitogen.ssh.Stream
def _sudo_method():
import mitogen.sudo
return mitogen.sudo.Stream
METHOD_NAMES = {
'local': _local_method,
'ssh': _ssh_method,
'sudo': _sudo_method,
}
def upgrade_router(econtext):
if not isinstance(econtext.router, Router): # TODO
econtext.router.__class__ = Router # TODO
econtext.router.id_allocator = ChildIdAllocator(econtext.router)
LOG.debug('_proxy_connect(): constructing ModuleForwarder')
ModuleForwarder(econtext.router, econtext.parent, econtext.importer)
@mitogen.core.takes_econtext
def _proxy_connect(name, context_id, method_name, kwargs, econtext):
upgrade_router(econtext)
context = econtext.router._connect(
context_id,
METHOD_NAMES[method_name](),
name=name,
**kwargs
)
return context.name
class IdAllocator(object):
def __init__(self, router):
self.router = router
self.next_id = 1
self.lock = threading.Lock()
router.add_handler(self.on_allocate_id, mitogen.core.ALLOCATE_ID)
def __repr__(self):
return 'IdAllocator(%r)' % (self.router,)
def allocate(self):
self.lock.acquire()
try:
id_ = self.next_id
self.next_id += 1
return id_
finally:
self.lock.release()
def on_allocate_id(self, msg):
id_ = self.allocate()
requestee = self.router.context_by_id(msg.src_id)
allocated = self.router.context_by_id(id_, msg.src_id)
LOG.debug('%r: allocating %r to %r', self, allocated, requestee)
self.router.route(
mitogen.core.Message.pickled(
id_,
dst_id=msg.src_id,
handle=msg.reply_to,
)
)
LOG.debug('%r: publishing route to %r via %r', self,
allocated, requestee)
self.router.propagate_route(allocated, requestee)
class ChildIdAllocator(object):
def __init__(self, router):
self.router = router
def allocate(self):
master = Context(self.router, 0)
return master.send_await(
mitogen.core.Message(dst_id=0, handle=mitogen.core.ALLOCATE_ID)
)
class Router(mitogen.core.Router):
debug = False
profiling = False
def __init__(self, *args, **kwargs):
super(Router, self).__init__(*args, **kwargs)
self.id_allocator = IdAllocator(self)
self.responder = ModuleResponder(self)
self.log_forwarder = LogForwarder(self)
def enable_debug(self):
mitogen.core.enable_debug_logging()
self.debug = True
def __enter__(self):
return self
def __exit__(self, e_type, e_val, tb):
self.broker.shutdown()
self.broker.join()
def allocate_id(self):
return self.id_allocator.allocate()
def context_by_id(self, context_id, via_id=None):
context = self._context_by_id.get(context_id)
if context is None:
context = Context(self, context_id)
if via_id is not None:
context.via = self.context_by_id(via_id)
self._context_by_id[context_id] = context
return context
def local(self, **kwargs):
return self.connect('local', **kwargs)
def sudo(self, **kwargs):
return self.connect('sudo', **kwargs)
def ssh(self, **kwargs):
return self.connect('ssh', **kwargs)
def _connect(self, context_id, klass, name=None, **kwargs):
context = Context(self, context_id)
stream = klass(self, context.context_id, **kwargs)
if name is not None:
stream.name = name
stream.connect()
context.name = stream.name
self.register(context, stream)
return context
def connect(self, method_name, name=None, **kwargs):
klass = METHOD_NAMES[method_name]()
kwargs.setdefault('debug', self.debug)
kwargs.setdefault('profiling', self.profiling)
via = kwargs.pop('via', None)
if via is not None:
return self.proxy_connect(via, method_name, name=name, **kwargs)
context_id = self.allocate_id()
return self._connect(context_id, klass, name=name, **kwargs)
def propagate_route(self, target, via):
self.add_route(target.context_id, via.context_id)
child = via
parent = via.via
while parent is not None:
LOG.debug('Adding route to %r for %r via %r', parent, target, child)
parent.send(
mitogen.core.Message(
data='%s\x00%s' % (target.context_id, child.context_id),
handle=mitogen.core.ADD_ROUTE,
)
)
child = parent
parent = parent.via
def proxy_connect(self, via_context, method_name, name=None, **kwargs):
context_id = self.allocate_id()
# Must be added prior to _proxy_connect() to avoid a race.
self.add_route(context_id, via_context.context_id)
name = via_context.call(_proxy_connect,
name, context_id, method_name, kwargs
)
name = '%s.%s' % (via_context.name, name)
context = Context(self, context_id, name=name)
context.via = via_context
self._context_by_id[context.context_id] = context
self.propagate_route(context, via_context)
return context
class ProcessMonitor(object):
def __init__(self):
# pid -> callback()
self.callback_by_pid = {}
signal.signal(signal.SIGCHLD, self._on_sigchld)
def _on_sigchld(self, _signum, _frame):
for pid, callback in self.callback_by_pid.items():
pid, status = os.waitpid(pid, os.WNOHANG)
if pid:
callback(status)
del self.callback_by_pid[pid]
def add(self, pid, callback):
self.callback_by_pid[pid] = callback
_instance = None
@classmethod
def instance(cls):
if cls._instance is None:
cls._instance = cls()
return cls._instance