# Copyright 2019, David Wilson # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # 1. Redistributions of source code must retain the above copyright notice, # this list of conditions and the following disclaimer. # # 2. 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. # # 3. Neither the name of the copyright holder 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 HOLDER 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. # !mitogen: minify_safe """ This module implements functionality required by master processes, such as starting new contexts via SSH. Its size is also restricted, since it must be sent to any context that will be used to establish additional child contexts. """ import dis import imp import inspect import itertools import logging import os import pkgutil import re import string import sys import time import threading import types import zlib 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 import mitogen.core import mitogen.minify import mitogen.parent from mitogen.core import b from mitogen.core import IOLOG from mitogen.core import LOG from mitogen.core import str_partition from mitogen.core import str_rpartition from mitogen.core import to_text imap = getattr(itertools, 'imap', map) izip = getattr(itertools, 'izip', zip) try: any except NameError: from mitogen.core import any try: next except NameError: from mitogen.core import next RLOG = logging.getLogger('mitogen.ctx') def _stdlib_paths(): """Return a set of paths from which Python imports the standard library. """ attr_candidates = [ 'prefix', 'real_prefix', # virtualenv: only set inside a virtual environment. 'base_prefix', # venv: always set, equal to prefix if outside. ] prefixes = (getattr(sys, a) for a in attr_candidates if hasattr(sys, a)) version = 'python%s.%s' % sys.version_info[0:2] return set(os.path.abspath(os.path.join(p, 'lib', version)) for p in prefixes) def is_stdlib_name(modname): """Return :data:`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 = os.path.abspath(getattr(module, '__file__', '')) return is_stdlib_path(modpath) _STDLIB_PATHS = _stdlib_paths() def is_stdlib_path(path): return any( os.path.commonprefix((libpath, path)) == libpath and 'site-packages' not in path and 'dist-packages' not in path for libpath in _STDLIB_PATHS ) def get_child_modules(path): """Return the suffixes of submodules directly neated beneath of the package directory at `path`. :param str path: Path to the module's source code on disk, or some PEP-302-recognized equivalent. Usually this is the module's ``__file__`` attribute, but is specified explicitly to avoid loading the module. :return: List of submodule name suffixes. """ it = pkgutil.iter_modules([os.path.dirname(path)]) return [to_text(name) for _, name, _ in it] def _get_core_source(): """ Master version of parent.get_core_source(). """ source = inspect.getsource(mitogen.core) return mitogen.minify.minimize_source(source) if mitogen.is_master: # TODO: find a less surprising way of installing this. mitogen.parent._get_core_source = _get_core_source LOAD_CONST = dis.opname.index('LOAD_CONST') IMPORT_NAME = dis.opname.index('IMPORT_NAME') def _getarg(nextb, c): if c >= dis.HAVE_ARGUMENT: return nextb() | (nextb() << 8) if sys.version_info < (3, 0): def iter_opcodes(co): # Yield `(op, oparg)` tuples from the code object `co`. ordit = imap(ord, co.co_code) nextb = ordit.next return ((c, _getarg(nextb, c)) for c in ordit) elif sys.version_info < (3, 6): def iter_opcodes(co): # Yield `(op, oparg)` tuples from the code object `co`. ordit = iter(co.co_code) nextb = ordit.__next__ return ((c, _getarg(nextb, c)) for c in ordit) else: def iter_opcodes(co): # Yield `(op, oparg)` tuples from the code object `co`. ordit = iter(co.co_code) nextb = ordit.__next__ # https://github.com/abarnert/cpython/blob/c095a32f/Python/wordcode.md return ((c, nextb()) for c in ordit) def scan_code_imports(co): """ 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`. """ opit = iter_opcodes(co) opit, opit2, opit3 = itertools.tee(opit, 3) try: next(opit2) next(opit3) next(opit3) except StopIteration: return if sys.version_info >= (2, 5): for oparg1, oparg2, (op3, arg3) in 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 ()) else: # Python 2.4 did not yet have 'level', so stack format differs. for oparg1, (op2, arg2) in izip(opit, opit2): if op2 == IMPORT_NAME: op1, arg1 = oparg1 if op1 == LOAD_CONST: yield (-1, co.co_names[arg2], co.co_consts[arg1] or ()) class ThreadWatcher(object): """ Manage threads that wait for another thread to shut down, before invoking `on_join()` for each associated ThreadWatcher. In CPython it seems possible to use this method to ensure a non-main thread is signalled when the main thread has exited, using a third thread as a proxy. """ #: Protects remaining _cls_* members. _cls_lock = threading.Lock() #: PID of the process that last modified the class data. If the PID #: changes, it means the thread watch dict refers to threads that no longer #: exist in the current process (since it forked), and so must be reset. _cls_pid = None #: Map watched Thread -> list of ThreadWatcher instances. _cls_instances_by_target = {} #: Map watched Thread -> watcher Thread for each watched thread. _cls_thread_by_target = {} @classmethod def _reset(cls): """If we have forked since the watch dictionaries were initialized, all that has is garbage, so clear it.""" if os.getpid() != cls._cls_pid: cls._cls_pid = os.getpid() cls._cls_instances_by_target.clear() cls._cls_thread_by_target.clear() def __init__(self, target, on_join): self.target = target self.on_join = on_join @classmethod def _watch(cls, target): target.join() for watcher in cls._cls_instances_by_target[target]: watcher.on_join() def install(self): self._cls_lock.acquire() try: self._reset() lst = self._cls_instances_by_target.setdefault(self.target, []) lst.append(self) if self.target not in self._cls_thread_by_target: self._cls_thread_by_target[self.target] = threading.Thread( name='mitogen.master.join_thread_async', target=self._watch, args=(self.target,) ) self._cls_thread_by_target[self.target].start() finally: self._cls_lock.release() def remove(self): self._cls_lock.acquire() try: self._reset() lst = self._cls_instances_by_target.get(self.target, []) if self in lst: lst.remove(self) finally: self._cls_lock.release() @classmethod def watch(cls, target, on_join): watcher = cls(target, on_join) watcher.install() return watcher class LogForwarder(object): """ Install a :data:`mitogen.core.FORWARD_LOG` handler that delivers forwarded log events into the local logging framework. This is used by the master's :class:`Router`. The forwarded :class:`logging.LogRecord` objects are delivered to loggers under ``mitogen.ctx.*`` corresponding to their :attr:`mitogen.core.Context.name`, with the message prefixed with the logger name used in the child. The records include some extra attributes: * ``mitogen_message``: Unicode original message without the logger name prepended. * ``mitogen_context``: :class:`mitogen.parent.Context` reference to the source context. * ``mitogen_name``: Original logger name. :param mitogen.master.Router router: Router to install the handler on. """ def __init__(self, router): self._router = router self._cache = {} router.add_handler( fn=self._on_forward_log, handle=mitogen.core.FORWARD_LOG, ) def _on_forward_log(self, msg): if msg.is_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('%s: dropping log from unknown context ID %d', self, 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.decode('latin1').split('\x00', 2) # See logging.Handler.makeRecord() record = logging.LogRecord( name=logger.name, level=int(level_s), pathname='(unknown file)', lineno=0, msg=('%s: %s' % (name, s)), args=(), exc_info=None, ) record.mitogen_message = s record.mitogen_context = self._router.context_by_id(msg.src_id) record.mitogen_name = name logger.handle(record) def __repr__(self): return 'LogForwarder(%r)' % (self._router,) class ModuleFinder(object): """ Given the name of a loaded module, make a best-effort attempt at finding related modules likely needed by a child context requesting the original module. """ 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 _looks_like_script(self, path): """ Return :data:`True` if the (possibly extensionless) file at `path` resembles a Python script. For now we simply verify the file contains ASCII text. """ fp = open(path, 'rb') try: sample = fp.read(512).decode('latin-1') return not set(sample).difference(string.printable) finally: fp.close() def _py_filename(self, path): if not path: return None if path[-4:] in ('.pyc', '.pyo'): path = path.rstrip('co') if path.endswith('.py'): return path if os.path.exists(path) and self._looks_like_script(path): return path def _get_main_module_defective_python_3x(self, fullname): """ Recent versions of Python 3.x introduced an incomplete notion of importer specs, and in doing so created permanent asymmetry in the :mod:`pkgutil` interface handling for the `__main__` module. Therefore we must handle `__main__` specially. """ if fullname != '__main__': return None mod = sys.modules.get(fullname) if not mod: return None path = getattr(mod, '__file__', None) if not (os.path.exists(path) and self._looks_like_script(path)): return None fp = open(path, 'rb') try: source = fp.read() finally: fp.close() return path, source, False 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(). """ try: # Pre-'import spec' this returned None, in Python3.6 it raises # ImportError. loader = pkgutil.find_loader(fullname) except ImportError: e = sys.exc_info()[1] LOG.debug('%r._get_module_via_pkgutil(%r): %s', self, fullname, e) return None IOLOG.debug('%r._get_module_via_pkgutil(%r) -> %r', self, fullname, loader) if not loader: return try: path = self._py_filename(loader.get_filename(fullname)) source = loader.get_source(fullname) is_pkg = loader.is_package(fullname) except (AttributeError, ImportError): # - Per PEP-302, get_source() and is_package() are optional, # calling them may throw AttributeError. # - get_filename() may throw ImportError if pkgutil.find_loader() # picks a "parent" package's loader for some crap that's been # stuffed in sys.modules, for example in the case of urllib3: # "loader for urllib3.contrib.pyopenssl cannot handle # requests.packages.urllib3.contrib.pyopenssl" e = sys.exc_info()[1] LOG.debug('%r: loading %r using %r failed: %s', self, fullname, loader, e) return if path is None or source is None: return if isinstance(source, mitogen.core.UnicodeType): # get_source() returns "string" according to PEP-302, which was # reinterpreted for Python 3 to mean a Unicode string. source = source.encode('utf-8') return path, source, is_pkg 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) LOG.debug('_get_module_via_sys_modules(%r) -> %r', fullname, module) if not isinstance(module, types.ModuleType): LOG.debug('sys.modules[%r] absent or not a regular module', fullname) return path = self._py_filename(getattr(module, '__file__', '')) if not path: return is_pkg = hasattr(module, '__path__') try: source = inspect.getsource(module) except IOError: # Work around inspect.getsourcelines() bug for 0-byte __init__.py # files. if not is_pkg: raise source = '\n' if isinstance(source, mitogen.core.UnicodeType): # get_source() returns "string" according to PEP-302, which was # reinterpreted for Python 3 to mean a Unicode string. source = source.encode('utf-8') return path, source, is_pkg def _get_module_via_parent_enumeration(self, fullname): """ Attempt to fetch source code by examining the module's (hopefully less insane) parent package. Required for older versions of ansible.compat.six and plumbum.colors. """ if fullname not in sys.modules: # Don't attempt this unless a module really exists in sys.modules, # else we could return junk. return pkgname, _, modname = str_rpartition(to_text(fullname), u'.') pkg = sys.modules.get(pkgname) if pkg is None or not hasattr(pkg, '__file__'): return pkg_path = os.path.dirname(pkg.__file__) try: fp, path, ext = imp.find_module(modname, [pkg_path]) try: path = self._py_filename(path) if not path: fp.close() return source = fp.read() finally: if fp: fp.close() if isinstance(source, mitogen.core.UnicodeType): # get_source() returns "string" according to PEP-302, which was # reinterpreted for Python 3 to mean a Unicode string. source = source.encode('utf-8') return path, source, False except ImportError: e = sys.exc_info()[1] LOG.debug('imp.find_module(%r, %r) -> %s', modname, [pkg_path], e) def add_source_override(self, fullname, path, source, is_pkg): """ Explicitly install a source cache entry, preventing usual lookup methods from being used. Beware the value of `path` is critical when `is_pkg` is specified, since it directs where submodules are searched for. :param str fullname: Name of the module to override. :param str path: Module's path as it will appear in the cache. :param bytes source: Module source code as a bytestring. :param bool is_pkg: :data:`True` if the module is a package. """ self._found_cache[fullname] = (path, source, is_pkg) get_module_methods = [ _get_main_module_defective_python_3x, _get_module_via_pkgutil, _get_module_via_sys_modules, _get_module_via_parent_enumeration, ] 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 :data:`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: #LOG.debug('%r returned %r', method, tup) break else: tup = None, None, None LOG.debug('get_module_source(%r): cannot find source', fullname) self._found_cache[fullname] = tup return tup 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. """ mod = sys.modules.get(fullname, None) if hasattr(mod, '__path__'): fullname += '.__init__' 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, _, _ = str_rpartition(to_text(fullname), u'.') yield fullname def find_related_imports(self, fullname): """ Return a list of non-stdlib modules that are directly imported by `fullname`, plus their parents. The list is determined by retrieving the source code of `fullname`, compiling it, and examining all IMPORT_NAME ops. :param fullname: Fully qualified name of an _already imported_ module for which source code can be retrieved :type fullname: str """ related = self._related_cache.get(fullname) if related is not None: return related modpath, src, _ = self.get_module_source(fullname) if src is None: 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 = [ '%s%s' % (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( mitogen.core.to_text(name) for name in maybe_names if sys.modules.get(name) is not None and not is_stdlib_name(name) and u'six.moves' not in name # TODO: crap ) )) def find_related(self, fullname): """ Return a list of non-stdlib modules that are imported directly or indirectly by `fullname`, plus their parents. This method is like :py:meth:`find_related_imports`, but also recursively searches any modules which are imported by `fullname`. :param fullname: Fully qualified name of an _already imported_ module for which source code can be retrieved :type fullname: str """ stack = [fullname] found = set() while stack: name = stack.pop(0) names = self.find_related_imports(name) stack.extend(set(names).difference(set(found).union(stack))) found.update(names) found.discard(fullname) return sorted(found) class ModuleResponder(object): def __init__(self, router): self._router = router self._finder = ModuleFinder() self._cache = {} # fullname -> pickled self.blacklist = [] self.whitelist = [''] #: Context -> set([fullname, ..]) self._forwarded_by_context = {} #: Number of GET_MODULE messages received. self.get_module_count = 0 #: Total time spent in uncached GET_MODULE. self.get_module_secs = 0.0 #: Total time spent minifying modules. self.minify_secs = 0.0 #: Number of successful LOAD_MODULE messages sent. self.good_load_module_count = 0 #: Total bytes in successful LOAD_MODULE payloads. self.good_load_module_size = 0 #: Number of negative LOAD_MODULE messages sent. self.bad_load_module_count = 0 router.add_handler( fn=self._on_get_module, handle=mitogen.core.GET_MODULE, ) def __repr__(self): return 'ModuleResponder(%r)' % (self._router,) def add_source_override(self, fullname, path, source, is_pkg): """ See :meth:`ModuleFinder.add_source_override. """ self._finder.add_source_override(fullname, path, source, is_pkg) MAIN_RE = re.compile(b(r'^if\s+__name__\s*==\s*.__main__.\s*:'), re.M) main_guard_msg = ( "A child context attempted to import __main__, however the main " "module present in the master process lacks an execution guard. " "Update %r to prevent unintended execution, using a guard like:\n" "\n" " if __name__ == '__main__':\n" " # your code here.\n" ) def whitelist_prefix(self, fullname): if self.whitelist == ['']: self.whitelist = ['mitogen'] self.whitelist.append(fullname) def blacklist_prefix(self, fullname): self.blacklist.append(fullname) def neutralize_main(self, path, 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()] if b('mitogen.main(') in src: return src LOG.error(self.main_guard_msg, path) raise ImportError('refused') def _make_negative_response(self, fullname): return (fullname, None, None, None, ()) minify_safe_re = re.compile(b(r'\s+#\s*!mitogen:\s*minify_safe')) def _build_tuple(self, fullname): if fullname in self._cache: return self._cache[fullname] if mitogen.core.is_blacklisted_import(self, fullname): raise ImportError('blacklisted') path, source, is_pkg = self._finder.get_module_source(fullname) if path and is_stdlib_path(path): # Prevent loading of 2.x<->3.x stdlib modules! This costs one # RTT per hit, so a client-side solution is also required. LOG.debug('%r: refusing to serve stdlib module %r', self, fullname) tup = self._make_negative_response(fullname) self._cache[fullname] = tup return tup if source is None: # TODO: make this .warning() or similar again once importer has its # own logging category. LOG.debug('_build_tuple(%r): could not locate source', fullname) tup = self._make_negative_response(fullname) self._cache[fullname] = tup return tup if self.minify_safe_re.search(source): # If the module contains a magic marker, it's safe to minify. t0 = time.time() source = mitogen.minify.minimize_source(source).encode('utf-8') self.minify_secs += time.time() - t0 if is_pkg: pkg_present = get_child_modules(path) LOG.debug('_build_tuple(%r, %r) -> %r', path, fullname, pkg_present) else: pkg_present = None if fullname == '__main__': source = self.neutralize_main(path, source) compressed = mitogen.core.Blob(zlib.compress(source, 9)) related = [ to_text(name) for name in self._finder.find_related(fullname) if not mitogen.core.is_blacklisted_import(self, name) ] # 0:fullname 1:pkg_present 2:path 3:compressed 4:related tup = ( to_text(fullname), pkg_present, to_text(path), compressed, related ) self._cache[fullname] = tup return tup def _send_load_module(self, stream, fullname): if fullname not in stream.sent_modules: tup = self._build_tuple(fullname) msg = mitogen.core.Message.pickled( tup, dst_id=stream.remote_id, handle=mitogen.core.LOAD_MODULE, ) LOG.debug('%s: sending module %s (%.2f KiB)', stream.name, fullname, len(msg.data) / 1024.0) self._router._async_route(msg) stream.sent_modules.add(fullname) if tup[2] is not None: self.good_load_module_count += 1 self.good_load_module_size += len(msg.data) else: self.bad_load_module_count += 1 def _send_module_load_failed(self, stream, fullname): self.bad_load_module_count += 1 stream.send( mitogen.core.Message.pickled( self._make_negative_response(fullname), dst_id=stream.remote_id, handle=mitogen.core.LOAD_MODULE, ) ) def _send_module_and_related(self, stream, fullname): if fullname in stream.sent_modules: return try: tup = self._build_tuple(fullname) for name in tup[4]: # related parent, _, _ = str_partition(name, '.') if parent != fullname and parent not in stream.sent_modules: # Parent hasn't been sent, so don't load submodule yet. continue self._send_load_module(stream, name) self._send_load_module(stream, fullname) except Exception: LOG.debug('While importing %r', fullname, exc_info=True) self._send_module_load_failed(stream, fullname) def _on_get_module(self, msg): if msg.is_dead: return stream = self._router.stream_by_id(msg.src_id) if stream is None: return fullname = msg.data.decode() LOG.debug('%s requested module %s', stream.name, fullname) self.get_module_count += 1 if fullname in stream.sent_modules: LOG.warning('_on_get_module(): dup request for %r from %r', fullname, stream) t0 = time.time() try: self._send_module_and_related(stream, fullname) finally: self.get_module_secs += time.time() - t0 def _send_forward_module(self, stream, context, fullname): if stream.remote_id != context.context_id: stream.send( mitogen.core.Message( data=b('%s\x00%s' % (context.context_id, fullname)), handle=mitogen.core.FORWARD_MODULE, dst_id=stream.remote_id, ) ) def _forward_one_module(self, context, fullname): forwarded = self._forwarded_by_context.get(context) if forwarded is None: forwarded = set() self._forwarded_by_context[context] = forwarded if fullname in forwarded: return path = [] while fullname: path.append(fullname) fullname, _, _ = str_rpartition(fullname, u'.') stream = self._router.stream_by_id(context.context_id) if stream is None: LOG.debug('%r: dropping forward of %s to no longer existent ' '%r', self, path[0], context) return for fullname in reversed(path): self._send_module_and_related(stream, fullname) self._send_forward_module(stream, context, fullname) def _forward_modules(self, context, fullnames): IOLOG.debug('%r._forward_modules(%r, %r)', self, context, fullnames) for fullname in fullnames: self._forward_one_module(context, mitogen.core.to_text(fullname)) def forward_modules(self, context, fullnames): self._router.broker.defer(self._forward_modules, context, fullnames) class Broker(mitogen.core.Broker): """ .. note:: You may construct as many brokers as desired, and use the same broker for multiple routers, however usually only one broker need exist. Multiple brokers may be useful when dealing with sets of children with differing lifetimes. For example, a subscription service where non-payment results in termination for one customer. :param bool install_watcher: If :data:`True`, an additional thread is started to monitor the lifetime of the main thread, triggering :meth:`shutdown` automatically in case the user forgets to call it, or their code crashed. You should not rely on this functionality in your program, it is only intended as a fail-safe and to simplify the API for new users. In particular, alternative Python implementations may not be able to support watching the main thread. """ shutdown_timeout = 5.0 _watcher = None poller_class = mitogen.parent.PREFERRED_POLLER def __init__(self, install_watcher=True): if install_watcher: self._watcher = ThreadWatcher.watch( target=threading.currentThread(), on_join=self.shutdown, ) super(Broker, self).__init__() def shutdown(self): super(Broker, self).shutdown() if self._watcher: self._watcher.remove() class Router(mitogen.parent.Router): """ Extend :class:`mitogen.core.Router` with functionality useful to masters, and child contexts who later become masters. Currently when this class is required, the target context's router is upgraded at runtime. .. note:: You may construct as many routers as desired, and use the same broker for multiple routers, however usually only one broker and router need exist. Multiple routers may be useful when dealing with separate trust domains, for example, manipulating infrastructure belonging to separate customers or projects. :param mitogen.master.Broker broker: Broker to use. If not specified, a private :class:`Broker` is created. :param int max_message_size: Override the maximum message size this router is willing to receive or transmit. Any value set here is automatically inherited by any children created by the router. This has a liberal default of 128 MiB, but may be set much lower. Beware that setting it below 64KiB may encourage unexpected failures as parents and children can no longer route large Python modules that may be required by your application. """ broker_class = Broker #: When :data:`True`, cause the broker thread and any subsequent broker and #: main threads existing in any child to write #: ``/tmp/mitogen.stats...log`` containing a #: :mod:`cProfile` dump on graceful exit. Must be set prior to construction #: of any :class:`Broker`, e.g. via:: #: #: mitogen.master.Router.profiling = True profiling = os.environ.get('MITOGEN_PROFILING') is not None def __init__(self, broker=None, max_message_size=None): if broker is None: broker = self.broker_class() if max_message_size: self.max_message_size = max_message_size super(Router, self).__init__(broker) self.upgrade() def upgrade(self): self.id_allocator = IdAllocator(self) self.responder = ModuleResponder(self) self.log_forwarder = LogForwarder(self) self.route_monitor = mitogen.parent.RouteMonitor(router=self) self.add_handler( # TODO: cutpaste. fn=self._on_detaching, handle=mitogen.core.DETACHING, persist=True, ) def _on_broker_exit(self): super(Router, self)._on_broker_exit() dct = self.get_stats() dct['self'] = self dct['minify_ms'] = 1000 * dct['minify_secs'] dct['get_module_ms'] = 1000 * dct['get_module_secs'] dct['good_load_module_size_kb'] = dct['good_load_module_size'] / 1024.0 dct['good_load_module_size_avg'] = ( ( dct['good_load_module_size'] / (float(dct['good_load_module_count']) or 1.0) ) / 1024.0 ) LOG.debug( '%(self)r: stats: ' '%(get_module_count)d module requests in ' '%(get_module_ms)d ms, ' '%(good_load_module_count)d sent ' '(%(minify_ms)d ms minify time), ' '%(bad_load_module_count)d negative responses. ' 'Sent %(good_load_module_size_kb).01f kb total, ' '%(good_load_module_size_avg).01f kb avg.' % dct ) def get_stats(self): """ Return performance data for the module responder. :returns: Dict containing keys: * `get_module_count`: Integer count of :data:`mitogen.core.GET_MODULE` messages received. * `get_module_secs`: Floating point total seconds spent servicing :data:`mitogen.core.GET_MODULE` requests. * `good_load_module_count`: Integer count of successful :data:`mitogen.core.LOAD_MODULE` messages sent. * `good_load_module_size`: Integer total bytes sent in :data:`mitogen.core.LOAD_MODULE` message payloads. * `bad_load_module_count`: Integer count of negative :data:`mitogen.core.LOAD_MODULE` messages sent. * `minify_secs`: CPU seconds spent minifying modules marked minify-safe. """ return { 'get_module_count': self.responder.get_module_count, 'get_module_secs': self.responder.get_module_secs, 'good_load_module_count': self.responder.good_load_module_count, 'good_load_module_size': self.responder.good_load_module_size, 'bad_load_module_count': self.responder.bad_load_module_count, 'minify_secs': self.responder.minify_secs, } def enable_debug(self): """ Cause this context and any descendant child contexts to write debug logs to ``/tmp/mitogen..log``. """ 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 disconnect_stream(self, stream): self.broker.defer(stream.on_disconnect, self.broker) def disconnect_all(self): for stream in self._stream_by_id.values(): self.disconnect_stream(stream) class IdAllocator(object): def __init__(self, router): self.router = router self.next_id = 1 self.lock = threading.Lock() router.add_handler( fn=self.on_allocate_id, handle=mitogen.core.ALLOCATE_ID, ) def __repr__(self): return 'IdAllocator(%r)' % (self.router,) BLOCK_SIZE = 1000 def allocate(self): """ Arrange for a unique context ID to be allocated and associated with a route leading to the active context. In masters, the ID is generated directly, in children it is forwarded to the master via a :data:`mitogen.core.ALLOCATE_ID` message. """ self.lock.acquire() try: id_ = self.next_id self.next_id += 1 return id_ finally: self.lock.release() def allocate_block(self): self.lock.acquire() try: id_ = self.next_id self.next_id += self.BLOCK_SIZE end_id = id_ + self.BLOCK_SIZE LOG.debug('%r: allocating [%d..%d)', self, id_, end_id) return id_, end_id finally: self.lock.release() def on_allocate_id(self, msg): if msg.is_dead: return id_, last_id = self.allocate_block() requestee = self.router.context_by_id(msg.src_id) LOG.debug('%r: allocating [%r..%r) to %r', self, id_, last_id, requestee) msg.reply((id_, last_id))