############################################################################### # Prepares and processes the data to setup the new process environment # # author: Thomas Moreau and Olivier Grisel # # adapted from multiprocessing/spawn.py (17/02/2017) # * Improve logging data # import os import sys import runpy import types from multiprocessing import process, util if sys.platform != 'win32': WINEXE = False WINSERVICE = False else: import msvcrt from .reduction import duplicate WINEXE = (sys.platform == 'win32' and getattr(sys, 'frozen', False)) WINSERVICE = sys.executable.lower().endswith("pythonservice.exe") if WINSERVICE: _python_exe = os.path.join(sys.exec_prefix, 'python.exe') else: _python_exe = sys.executable def get_executable(): return _python_exe def _check_not_importing_main(): if getattr(process.current_process(), '_inheriting', False): raise RuntimeError(''' An attempt has been made to start a new process before the current process has finished its bootstrapping phase. This probably means that you are not using fork to start your child processes and you have forgotten to use the proper idiom in the main module: if __name__ == '__main__': freeze_support() ... The "freeze_support()" line can be omitted if the program is not going to be frozen to produce an executable.''') def get_preparation_data(name, init_main_module=True): ''' Return info about parent needed by child to unpickle process object ''' _check_not_importing_main() d = dict( log_to_stderr=util._log_to_stderr, authkey=bytes(process.current_process().authkey), name=name, sys_argv=sys.argv, orig_dir=process.ORIGINAL_DIR, dir=os.getcwd() ) # Send sys_path and make sure the current directory will not be changed sys_path = [p for p in sys.path] try: i = sys_path.index('') except ValueError: pass else: sys_path[i] = process.ORIGINAL_DIR d['sys_path'] = sys_path # Make sure to pass the information if the multiprocessing logger is active if util._logger is not None: d['log_level'] = util._logger.getEffectiveLevel() if len(util._logger.handlers) > 0: h = util._logger.handlers[0] d['log_fmt'] = h.formatter._fmt # Tell the child how to communicate with the resource_tracker from .resource_tracker import _resource_tracker _resource_tracker.ensure_running() d["tracker_args"] = {"pid": _resource_tracker._pid} if sys.platform == "win32": child_w = duplicate( msvcrt.get_osfhandle(_resource_tracker._fd), inheritable=True) d["tracker_args"]["fh"] = child_w else: d["tracker_args"]["fd"] = _resource_tracker._fd if sys.version_info >= (3, 8) and os.name == 'posix': # joblib/loky#242: allow loky processes to retrieve the resource # tracker of their parent in case the child processes depickles # shared_memory objects, that are still tracked by multiprocessing's # resource_tracker by default. # XXX: this is a workaround that may be error prone: in the future, it # would be better to have loky subclass multiprocessing's shared_memory # to force registration of shared_memory segments via loky's # resource_tracker. from multiprocessing.resource_tracker import ( _resource_tracker as mp_resource_tracker ) # multiprocessing's resource_tracker must be running before loky # process is created (othewise the child won't be able to use it if it # is created later on) mp_resource_tracker.ensure_running() d["mp_tracker_args"] = { 'fd': mp_resource_tracker._fd, 'pid': mp_resource_tracker._pid } # Figure out whether to initialise main in the subprocess as a module # or through direct execution (or to leave it alone entirely) if init_main_module: main_module = sys.modules['__main__'] try: main_mod_name = getattr(main_module.__spec__, "name", None) except BaseException: main_mod_name = None if main_mod_name is not None: d['init_main_from_name'] = main_mod_name elif sys.platform != 'win32' or (not WINEXE and not WINSERVICE): main_path = getattr(main_module, '__file__', None) if main_path is not None: if (not os.path.isabs(main_path) and process.ORIGINAL_DIR is not None): main_path = os.path.join(process.ORIGINAL_DIR, main_path) d['init_main_from_path'] = os.path.normpath(main_path) # Compat for python2.7 d['main_path'] = d['init_main_from_path'] return d # # Prepare current process # old_main_modules = [] def prepare(data): ''' Try to get current process ready to unpickle process object ''' if 'name' in data: process.current_process().name = data['name'] if 'authkey' in data: process.current_process().authkey = data['authkey'] if 'log_to_stderr' in data and data['log_to_stderr']: util.log_to_stderr() if 'log_level' in data: util.get_logger().setLevel(data['log_level']) if 'log_fmt' in data: import logging util.get_logger().handlers[0].setFormatter( logging.Formatter(data['log_fmt']) ) if 'sys_path' in data: sys.path = data['sys_path'] if 'sys_argv' in data: sys.argv = data['sys_argv'] if 'dir' in data: os.chdir(data['dir']) if 'orig_dir' in data: process.ORIGINAL_DIR = data['orig_dir'] if 'mp_tracker_args' in data: from multiprocessing.resource_tracker import ( _resource_tracker as mp_resource_tracker ) mp_resource_tracker._fd = data['mp_tracker_args']['fd'] mp_resource_tracker._pid = data['mp_tracker_args']['pid'] if 'tracker_args' in data: from .resource_tracker import _resource_tracker _resource_tracker._pid = data["tracker_args"]['pid'] if sys.platform == 'win32': handle = data["tracker_args"]["fh"] _resource_tracker._fd = msvcrt.open_osfhandle(handle, 0) else: _resource_tracker._fd = data["tracker_args"]["fd"] if 'init_main_from_name' in data: _fixup_main_from_name(data['init_main_from_name']) elif 'init_main_from_path' in data: _fixup_main_from_path(data['init_main_from_path']) # Multiprocessing module helpers to fix up the main module in # spawned subprocesses def _fixup_main_from_name(mod_name): # __main__.py files for packages, directories, zip archives, etc, run # their "main only" code unconditionally, so we don't even try to # populate anything in __main__, nor do we make any changes to # __main__ attributes current_main = sys.modules['__main__'] if mod_name == "__main__" or mod_name.endswith(".__main__"): return # If this process was forked, __main__ may already be populated if getattr(current_main.__spec__, "name", None) == mod_name: return # Otherwise, __main__ may contain some non-main code where we need to # support unpickling it properly. We rerun it as __mp_main__ and make # the normal __main__ an alias to that old_main_modules.append(current_main) main_module = types.ModuleType("__mp_main__") main_content = runpy.run_module(mod_name, run_name="__mp_main__", alter_sys=True) main_module.__dict__.update(main_content) sys.modules['__main__'] = sys.modules['__mp_main__'] = main_module def _fixup_main_from_path(main_path): # If this process was forked, __main__ may already be populated current_main = sys.modules['__main__'] # Unfortunately, the main ipython launch script historically had no # "if __name__ == '__main__'" guard, so we work around that # by treating it like a __main__.py file # See https://github.com/ipython/ipython/issues/4698 main_name = os.path.splitext(os.path.basename(main_path))[0] if main_name == 'ipython': return # Otherwise, if __file__ already has the setting we expect, # there's nothing more to do if getattr(current_main, '__file__', None) == main_path: return # If the parent process has sent a path through rather than a module # name we assume it is an executable script that may contain # non-main code that needs to be executed old_main_modules.append(current_main) main_module = types.ModuleType("__mp_main__") main_content = runpy.run_path(main_path, run_name="__mp_main__") main_module.__dict__.update(main_content) sys.modules['__main__'] = sys.modules['__mp_main__'] = main_module def import_main_path(main_path): ''' Set sys.modules['__main__'] to module at main_path ''' _fixup_main_from_path(main_path)