def run_command(self, command_list, filename, count, log_function): """Run command_list count times. Parameters ---------- command_list : list A list of args to provide to Popen. Each element of this list will be interpolated with the filename to convert. filename : unicode The name of the file to convert. count : int How many times to run the command. Returns ------- success : bool A boolean indicating if the command was successful (True) or failed (False). """ command = [c.format(filename=filename) for c in command_list] # On windows with python 2.x there is a bug in subprocess.Popen and # unicode commands are not supported if sys.platform == 'win32' and sys.version_info < (3,0): #We must use cp1252 encoding for calling subprocess.Popen #Note that sys.stdin.encoding and encoding.DEFAULT_ENCODING # could be different (cp437 in case of dos console) command = [c.encode('cp1252') for c in command] # This will throw a clearer error if the command is not found cmd = which(command_list[0]) if cmd is None: raise OSError("%s not found on PATH" % command_list[0]) times = 'time' if count == 1 else 'times' self.log.info("Running %s %i %s: %s", command_list[0], count, times, command) shell = (sys.platform == 'win32') if shell: command = subprocess.list2cmdline(command) env = os.environ.copy() env['TEXINPUTS'] = os.pathsep.join([ cast_bytes_py2(self.texinputs), env.get('TEXINPUTS', ''), ]) with open(os.devnull, 'rb') as null: stdout = subprocess.PIPE if not self.verbose else None for index in range(count): p = subprocess.Popen(command, stdout=stdout, stdin=null, shell=shell, env=env) out, err = p.communicate() if p.returncode: if self.verbose: # verbose means I didn't capture stdout with PIPE, # so it's already been displayed and `out` is None. out = u'' else: out = out.decode('utf-8', 'replace') log_function(command, out) return False # failure return True # success
def add_anchor(html, anchor_link_text=u'¶'): """Add an id and an anchor-link to an html header For use on markdown headings """ try: h = ElementTree.fromstring(py3compat.cast_bytes_py2(html, encoding='utf-8')) except Exception: # failed to parse, just return it unmodified return html link = _convert_header_id(html2text(h)) h.set('id', link) a = Element("a", {"class": "anchor-link", "href": "#" + link}) try: # Test if the anchor link text is HTML (e.g. an image) a.append(ElementTree.fromstring(anchor_link_text)) except Exception: # If we fail to parse, assume we've just got regular text a.text = anchor_link_text h.append(a) # Known issue of Python3.x, ElementTree.tostring() returns a byte string # instead of a text string. See issue http://bugs.python.org/issue10942 # Workaround is to make sure the bytes are casted to a string. return py3compat.decode(ElementTree.tostring(h), 'utf-8')
def import_item(name): """Import and return ``bar`` given the string ``foo.bar``. Calling ``bar = import_item("foo.bar")`` is the functional equivalent of executing the code ``from foo import bar``. Parameters ---------- name : string The fully qualified name of the module/package being imported. Returns ------- mod : module object The module that was imported. """ if not isinstance(name, str): raise TypeError("import_item accepts strings, not '%s'." % type(name)) name = cast_bytes_py2(name) parts = name.rsplit('.', 1) if len(parts) == 2: # called with 'foo.bar....' package, obj = parts module = __import__(package, fromlist=[obj]) try: pak = getattr(module, obj) except AttributeError: raise ImportError('No module named %s' % obj) return pak else: # called with un-dotted string return __import__(parts[0])
def import_item(name): """Import and return ``bar`` given the string ``foo.bar``. Calling ``bar = import_item("foo.bar")`` is the functional equivalent of executing the code ``from foo import bar``. Parameters ---------- name : string The fully qualified name of the module/package being imported. Returns ------- mod : module object The module that was imported. """ if not isinstance(name, string_types): raise TypeError("import_item accepts strings, not '%s'." % type(name)) name = cast_bytes_py2(name) parts = name.rsplit('.', 1) if len(parts) == 2: # called with 'foo.bar....' package, obj = parts module = __import__(package, fromlist=[obj]) try: pak = getattr(module, obj) except AttributeError: raise ImportError('No module named %s' % obj) return pak else: # called with un-dotted string return __import__(parts[0])
def add_anchor_lower_id(html, anchor_link_text="¶"): from xml.etree.cElementTree import Element from defusedxml import cElementTree as ElementTree from ipython_genutils import py3compat from nbconvert.filters.strings import _convert_header_id, html2text try: h = ElementTree.fromstring( py3compat.cast_bytes_py2(html, encoding="utf-8")) except Exception: # failed to parse, just return it unmodified return html link = _convert_header_id(html2text(h)) h.set("id", slugify(link)) a = Element("a", {"class": "anchor-link", "href": "#" + link}) try: # Test if the anchor link text is HTML (e.g. an image) a.append(ElementTree.fromstring(anchor_link_text)) except Exception: # If we fail to parse, assume we've just got regular text a.text = anchor_link_text h.append(a) # Known issue of Python3.x, ElementTree.tostring() returns a byte string # instead of a text string. See issue http://bugs.python.org/issue10942 # Workaround is to make sure the bytes are casted to a string. return py3compat.decode(ElementTree.tostring(h), "utf-8")
def prepend_to_env_search_path(varname, value, envdict): """Add value to the environment variable varname in envdict e.g. prepend_to_env_search_path('BIBINPUTS', '/home/sally/foo', os.environ) """ if not value: return # Nothing to add envdict[varname] = cast_bytes_py2(value) + os.pathsep + envdict.get(varname, '')
def tunnel_to_kernel(connection_info, sshserver, sshkey=None): """tunnel connections to a kernel via ssh This will open four SSH tunnels from localhost on this machine to the ports associated with the kernel. They can be either direct localhost-localhost tunnels, or if an intermediate server is necessary, the kernel must be listening on a public IP. Parameters ---------- connection_info : dict or str (path) Either a connection dict, or the path to a JSON connection file sshserver : str The ssh sever to use to tunnel to the kernel. Can be a full `user@server:port` string. ssh config aliases are respected. sshkey : str [optional] Path to file containing ssh key to use for authentication. Only necessary if your ssh config does not already associate a keyfile with the host. Returns ------- (shell, iopub, stdin, hb) : ints The four ports on localhost that have been forwarded to the kernel. """ from zmq.ssh import tunnel if isinstance(connection_info, string_types): # it's a path, unpack it with open(connection_info) as f: connection_info = json.loads(f.read()) cf = connection_info lports = tunnel.select_random_ports(4) rports = cf['shell_port'], cf['iopub_port'], cf['stdin_port'], cf[ 'hb_port'] remote_ip = cf['ip'] if tunnel.try_passwordless_ssh(sshserver, sshkey): password = False else: password = getpass("SSH Password for %s: " % cast_bytes_py2(sshserver)) for lp, rp in zip(lports, rports): tunnel.ssh_tunnel(lp, rp, sshserver, remote_ip, sshkey, password) return tuple(lports)
def tunnel_to_kernel(connection_info, sshserver, sshkey=None): """tunnel connections to a kernel via ssh This will open four SSH tunnels from localhost on this machine to the ports associated with the kernel. They can be either direct localhost-localhost tunnels, or if an intermediate server is necessary, the kernel must be listening on a public IP. Parameters ---------- connection_info : dict or str (path) Either a connection dict, or the path to a JSON connection file sshserver : str The ssh sever to use to tunnel to the kernel. Can be a full `user@server:port` string. ssh config aliases are respected. sshkey : str [optional] Path to file containing ssh key to use for authentication. Only necessary if your ssh config does not already associate a keyfile with the host. Returns ------- (shell, iopub, stdin, hb) : ints The four ports on localhost that have been forwarded to the kernel. """ from zmq.ssh import tunnel if isinstance(connection_info, string_types): # it's a path, unpack it with open(connection_info) as f: connection_info = json.loads(f.read()) cf = connection_info lports = tunnel.select_random_ports(4) rports = cf['shell_port'], cf['iopub_port'], cf['stdin_port'], cf['hb_port'] remote_ip = cf['ip'] if tunnel.try_passwordless_ssh(sshserver, sshkey): password=False else: password = getpass("SSH Password for %s: " % cast_bytes_py2(sshserver)) for lp,rp in zip(lports, rports): tunnel.ssh_tunnel(lp, rp, sshserver, remote_ip, sshkey, password) return tuple(lports)
def add_anchor(html): """Add an anchor-link to an html header For use on markdown headings """ try: h = ElementTree.fromstring(py3compat.cast_bytes_py2(html, encoding='utf-8')) except Exception: # failed to parse, just return it unmodified return html link = html2text(h).replace(' ', '-') h.set('id', link) a = ElementTree.Element("a", {"class" : "anchor-link", "href" : "#" + link}) a.text = u'¶' h.append(a) # Known issue of Python3.x, ElementTree.tostring() returns a byte string # instead of a text string. See issue http://bugs.python.org/issue10942 # Workaround is to make sure the bytes are casted to a string. return py3compat.decode(ElementTree.tostring(h), 'utf-8')
def launch_kernel(cmd, stdin=None, stdout=None, stderr=None, env=None, independent=False, cwd=None, **kw): """ Launches a localhost kernel, binding to the specified ports. Parameters ---------- cmd : Popen list, A string of Python code that imports and executes a kernel entry point. stdin, stdout, stderr : optional (default None) Standards streams, as defined in subprocess.Popen. independent : bool, optional (default False) If set, the kernel process is guaranteed to survive if this process dies. If not set, an effort is made to ensure that the kernel is killed when this process dies. Note that in this case it is still good practice to kill kernels manually before exiting. cwd : path, optional The working dir of the kernel process (default: cwd of this process). Returns ------- Popen instance for the kernel subprocess """ # Popen will fail (sometimes with a deadlock) if stdin, stdout, and stderr # are invalid. Unfortunately, there is in general no way to detect whether # they are valid. The following two blocks redirect them to (temporary) # pipes in certain important cases. # If this process has been backgrounded, our stdin is invalid. Since there # is no compelling reason for the kernel to inherit our stdin anyway, we'll # place this one safe and always redirect. redirect_in = True _stdin = PIPE if stdin is None else stdin # If this process in running on pythonw, we know that stdin, stdout, and # stderr are all invalid. redirect_out = sys.executable.endswith('pythonw.exe') if redirect_out: blackhole = open(os.devnull, 'w') _stdout = blackhole if stdout is None else stdout _stderr = blackhole if stderr is None else stderr else: _stdout, _stderr = stdout, stderr env = env if (env is not None) else os.environ.copy() encoding = getdefaultencoding(prefer_stream=False) kwargs = dict( stdin=_stdin, stdout=_stdout, stderr=_stderr, cwd=cwd, env=env, ) # Spawn a kernel. if sys.platform == 'win32': # Popen on Python 2 on Windows cannot handle unicode args or cwd cmd = [cast_bytes_py2(c, encoding) for c in cmd] if cwd: cwd = cast_bytes_py2(cwd, sys.getfilesystemencoding() or 'ascii') kwargs['cwd'] = cwd from .win_interrupt import create_interrupt_event # Create a Win32 event for interrupting the kernel # and store it in an environment variable. interrupt_event = create_interrupt_event() env["JPY_INTERRUPT_EVENT"] = str(interrupt_event) # deprecated old env name: env["IPY_INTERRUPT_EVENT"] = env["JPY_INTERRUPT_EVENT"] try: from _winapi import DuplicateHandle, GetCurrentProcess, \ DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP except: from _subprocess import DuplicateHandle, GetCurrentProcess, \ DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP # Launch the kernel process if independent: kwargs['creationflags'] = CREATE_NEW_PROCESS_GROUP else: pid = GetCurrentProcess() handle = DuplicateHandle( pid, pid, pid, 0, True, # Inheritable by new processes. DUPLICATE_SAME_ACCESS) env['JPY_PARENT_PID'] = str(int(handle)) else: if independent: kwargs['preexec_fn'] = lambda: os.setsid() else: # Create a new process group. This makes it easier to # interrupt the kernel, because we want to interrupt the # children of the kernel process also. kwargs['preexec_fn'] = lambda: os.setpgrp() env['JPY_PARENT_PID'] = str(os.getpid()) try: proc = Popen(cmd, **kwargs) except Exception as exc: msg = ("Failed to run command:\n{}\n" "with kwargs:\n{!r}\n") msg = msg.format(cmd, kwargs) get_logger().error(msg) raise if sys.platform == 'win32': # Attach the interrupt event to the Popen objet so it can be used later. proc.win32_interrupt_event = interrupt_event # Clean up pipes created to work around Popen bug. if redirect_in: if stdin is None: proc.stdin.close() return proc
def launch_kernel(cmd, stdin=None, stdout=None, stderr=None, env=None, independent=False, cwd=None, **kw): """ Launches a localhost kernel, binding to the specified ports. Parameters ---------- cmd : Popen list, A string of Python code that imports and executes a kernel entry point. stdin, stdout, stderr : optional (default None) Standards streams, as defined in subprocess.Popen. env: dict, optional Environment variables passed to the kernel independent : bool, optional (default False) If set, the kernel process is guaranteed to survive if this process dies. If not set, an effort is made to ensure that the kernel is killed when this process dies. Note that in this case it is still good practice to kill kernels manually before exiting. cwd : path, optional The working dir of the kernel process (default: cwd of this process). **kw: optional Additional arguments for Popen Returns ------- Popen instance for the kernel subprocess """ # Popen will fail (sometimes with a deadlock) if stdin, stdout, and stderr # are invalid. Unfortunately, there is in general no way to detect whether # they are valid. The following two blocks redirect them to (temporary) # pipes in certain important cases. # If this process has been backgrounded, our stdin is invalid. Since there # is no compelling reason for the kernel to inherit our stdin anyway, we'll # place this one safe and always redirect. redirect_in = True _stdin = PIPE if stdin is None else stdin # If this process in running on pythonw, we know that stdin, stdout, and # stderr are all invalid. redirect_out = sys.executable.endswith("pythonw.exe") if redirect_out: blackhole = open(os.devnull, "w") _stdout = blackhole if stdout is None else stdout _stderr = blackhole if stderr is None else stderr else: _stdout, _stderr = stdout, stderr env = env if (env is not None) else os.environ.copy() encoding = getdefaultencoding(prefer_stream=False) kwargs = kw.copy() main_args = dict( stdin=_stdin, stdout=_stdout, stderr=_stderr, cwd=cwd, env=env, ) kwargs.update(main_args) # Spawn a kernel. if sys.platform == "win32": # Popen on Python 2 on Windows cannot handle unicode args or cwd cmd = [cast_bytes_py2(c, encoding) for c in cmd] if cwd: cwd = cast_bytes_py2(cwd, sys.getfilesystemencoding() or "ascii") kwargs["cwd"] = cwd from .win_interrupt import create_interrupt_event # Create a Win32 event for interrupting the kernel # and store it in an environment variable. interrupt_event = create_interrupt_event() env["JPY_INTERRUPT_EVENT"] = str(interrupt_event) # deprecated old env name: env["IPY_INTERRUPT_EVENT"] = env["JPY_INTERRUPT_EVENT"] try: from _winapi import ( DuplicateHandle, GetCurrentProcess, DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP, ) except: from _subprocess import ( DuplicateHandle, GetCurrentProcess, DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP, ) # create a handle on the parent to be inherited if independent: kwargs["creationflags"] = CREATE_NEW_PROCESS_GROUP else: pid = GetCurrentProcess() handle = DuplicateHandle( pid, pid, pid, 0, True, # Inheritable by new processes. DUPLICATE_SAME_ACCESS, ) env["JPY_PARENT_PID"] = str(int(handle)) # Prevent creating new console window on pythonw if redirect_out: kwargs["creationflags"] = (kwargs.setdefault("creationflags", 0) | 0x08000000) # CREATE_NO_WINDOW # Avoid closing the above parent and interrupt handles. # close_fds is True by default on Python >=3.7 # or when no stream is captured on Python <3.7 # (we always capture stdin, so this is already False by default on <3.7) kwargs["close_fds"] = False else: # Create a new session. # This makes it easier to interrupt the kernel, # because we want to interrupt the whole process group. # We don't use setpgrp, which is known to cause problems for kernels starting # certain interactive subprocesses, such as bash -i. kwargs["start_new_session"] = True if not independent: env["JPY_PARENT_PID"] = str(os.getpid()) try: proc = Popen(cmd, **kwargs) except Exception as exc: msg = ("Failed to run command:\n{}\n" " PATH={!r}\n" " with kwargs:\n{!r}\n") # exclude environment variables, # which may contain access tokens and the like. without_env = { key: value for key, value in kwargs.items() if key != "env" } msg = msg.format(cmd, env.get("PATH", os.defpath), without_env) raise if sys.platform == "win32": # Attach the interrupt event to the Popen objet so it can be used later. proc.win32_interrupt_event = interrupt_event # Clean up pipes created to work around Popen bug. if redirect_in: if stdin is None: proc.stdin.close() return proc
def run_command(self, command_list, filename, count, log_function): """Run command_list count times. Parameters ---------- command_list : list A list of args to provide to Popen. Each element of this list will be interpolated with the filename to convert. filename : unicode The name of the file to convert. count : int How many times to run the command. Returns ------- success : bool A boolean indicating if the command was successful (True) or failed (False). """ command = [c.format(filename=filename) for c in command_list] # On windows with python 2.x there is a bug in subprocess.Popen and # unicode commands are not supported if sys.platform == 'win32' and sys.version_info < (3, 0): #We must use cp1252 encoding for calling subprocess.Popen #Note that sys.stdin.encoding and encoding.DEFAULT_ENCODING # could be different (cp437 in case of dos console) command = [c.encode('cp1252') for c in command] # This will throw a clearer error if the command is not found cmd = which(command_list[0]) if cmd is None: raise OSError("%s not found on PATH" % command_list[0]) times = 'time' if count == 1 else 'times' self.log.info("Running %s %i %s: %s", command_list[0], count, times, command) shell = (sys.platform == 'win32') if shell: command = subprocess.list2cmdline(command) env = os.environ.copy() env['TEXINPUTS'] = os.pathsep.join([ cast_bytes_py2(self.texinputs), env.get('TEXINPUTS', ''), ]) with open(os.devnull, 'rb') as null: stdout = subprocess.PIPE if not self.verbose else None for index in range(count): p = subprocess.Popen(command, stdout=stdout, stderr=subprocess.STDOUT, stdin=null, shell=shell, env=env) out, _ = p.communicate() if p.returncode: if self.verbose: # verbose means I didn't capture stdout with PIPE, # so it's already been displayed and `out` is None. out = u'' else: out = out.decode('utf-8', 'replace') log_function(command, out) self._captured_output.append(out) return False # failure return True # success
def __str__(self): u = self.__unicode__() return cast_bytes_py2(u)
def launch_kernel(cmd, stdin=None, stdout=None, stderr=None, env=None, independent=False, cwd=None, **kw): """ Launches a localhost kernel, binding to the specified ports. Parameters ---------- cmd : Popen list, A string of Python code that imports and executes a kernel entry point. stdin, stdout, stderr : optional (default None) Standards streams, as defined in subprocess.Popen. env: dict, optional Environment variables passed to the kernel independent : bool, optional (default False) If set, the kernel process is guaranteed to survive if this process dies. If not set, an effort is made to ensure that the kernel is killed when this process dies. Note that in this case it is still good practice to kill kernels manually before exiting. cwd : path, optional The working dir of the kernel process (default: cwd of this process). **kw: optional Additional arguments for Popen Returns ------- Popen instance for the kernel subprocess """ # Popen will fail (sometimes with a deadlock) if stdin, stdout, and stderr # are invalid. Unfortunately, there is in general no way to detect whether # they are valid. The following two blocks redirect them to (temporary) # pipes in certain important cases. # If this process has been backgrounded, our stdin is invalid. Since there # is no compelling reason for the kernel to inherit our stdin anyway, we'll # place this one safe and always redirect. redirect_in = True _stdin = PIPE if stdin is None else stdin # If this process in running on pythonw, we know that stdin, stdout, and # stderr are all invalid. redirect_out = sys.executable.endswith('pythonw.exe') if redirect_out: blackhole = open(os.devnull, 'w') _stdout = blackhole if stdout is None else stdout _stderr = blackhole if stderr is None else stderr else: _stdout, _stderr = stdout, stderr env = env if (env is not None) else os.environ.copy() encoding = getdefaultencoding(prefer_stream=False) kwargs = kw.copy() main_args = dict( stdin=_stdin, stdout=_stdout, stderr=_stderr, cwd=cwd, env=env, ) kwargs.update(main_args) # Spawn a kernel. if sys.platform == 'win32': # Popen on Python 2 on Windows cannot handle unicode args or cwd cmd = [ cast_bytes_py2(c, encoding) for c in cmd ] if cwd: cwd = cast_bytes_py2(cwd, sys.getfilesystemencoding() or 'ascii') kwargs['cwd'] = cwd from .win_interrupt import create_interrupt_event # Create a Win32 event for interrupting the kernel # and store it in an environment variable. interrupt_event = create_interrupt_event() env["JPY_INTERRUPT_EVENT"] = str(interrupt_event) # deprecated old env name: env["IPY_INTERRUPT_EVENT"] = env["JPY_INTERRUPT_EVENT"] try: from _winapi import DuplicateHandle, GetCurrentProcess, \ DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP except: from _subprocess import DuplicateHandle, GetCurrentProcess, \ DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP # create a handle on the parent to be inherited if independent: kwargs['creationflags'] = CREATE_NEW_PROCESS_GROUP else: pid = GetCurrentProcess() handle = DuplicateHandle(pid, pid, pid, 0, True, # Inheritable by new processes. DUPLICATE_SAME_ACCESS) env['JPY_PARENT_PID'] = str(int(handle)) # Prevent creating new console window on pythonw if redirect_out: kwargs['creationflags'] = kwargs.setdefault('creationflags', 0) | 0x08000000 # CREATE_NO_WINDOW # Avoid closing the above parent and interrupt handles. # close_fds is True by default on Python >=3.7 # or when no stream is captured on Python <3.7 # (we always capture stdin, so this is already False by default on <3.7) kwargs['close_fds'] = False else: # Create a new session. # This makes it easier to interrupt the kernel, # because we want to interrupt the whole process group. # We don't use setpgrp, which is known to cause problems for kernels starting # certain interactive subprocesses, such as bash -i. if PY3: kwargs['start_new_session'] = True else: kwargs['preexec_fn'] = lambda: os.setsid() if not independent: env['JPY_PARENT_PID'] = str(os.getpid()) try: proc = Popen(cmd, **kwargs) except Exception as exc: msg = ( "Failed to run command:\n{}\n" " PATH={!r}\n" " with kwargs:\n{!r}\n" ) # exclude environment variables, # which may contain access tokens and the like. without_env = {key:value for key, value in kwargs.items() if key != 'env'} msg = msg.format(cmd, env.get('PATH', os.defpath), without_env) get_logger().error(msg) raise if sys.platform == 'win32': # Attach the interrupt event to the Popen objet so it can be used later. proc.win32_interrupt_event = interrupt_event # Clean up pipes created to work around Popen bug. if redirect_in: if stdin is None: proc.stdin.close() return proc
def build_popen_kwargs(self, connection_file): """Build a dictionary of arguments to pass to Popen""" kwargs = {} # Popen will fail (sometimes with a deadlock) if stdin, stdout, and stderr # are invalid. Unfortunately, there is in general no way to detect whether # they are valid. The following two blocks redirect them to (temporary) # pipes in certain important cases. # If this process has been backgrounded, our stdin is invalid. Since there # is no compelling reason for the kernel to inherit our stdin anyway, we'll # place this one safe and always redirect. kwargs['stdin'] = PIPE # If this process in running on pythonw, we know that stdin, stdout, and # stderr are all invalid. redirect_out = sys.executable.endswith('pythonw.exe') if redirect_out: kwargs['stdout'] = kwargs['stderr'] = open(os.devnull, 'w') cmd = self.format_kernel_cmd(connection_file) kwargs['env'] = env = os.environ.copy() # Don't allow PYTHONEXECUTABLE to be passed to kernel process. # If set, it can bork all the things. env.pop('PYTHONEXECUTABLE', None) if self.extra_env: env.update(self.extra_env) # TODO: where is this used? independent = False if sys.platform == 'win32': # Popen on Python 2 on Windows cannot handle unicode args or cwd encoding = getdefaultencoding(prefer_stream=False) kwargs['args'] = [cast_bytes_py2(c, encoding) for c in cmd] if self.cwd: kwargs['cwd'] = cast_bytes_py2( self.cwd, sys.getfilesystemencoding() or 'ascii') try: # noinspection PyUnresolvedReferences from _winapi import DuplicateHandle, GetCurrentProcess, \ DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP except: # noinspection PyUnresolvedReferences from _subprocess import DuplicateHandle, GetCurrentProcess, \ DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP # Launch the kernel process if independent: kwargs['creationflags'] = CREATE_NEW_PROCESS_GROUP else: pid = GetCurrentProcess() handle = DuplicateHandle( pid, pid, pid, 0, True, # Inheritable by new processes. DUPLICATE_SAME_ACCESS) env['JPY_PARENT_PID'] = str(int(handle)) else: kwargs['args'] = cmd kwargs['cwd'] = self.cwd # Create a new session. # This makes it easier to interrupt the kernel, # because we want to interrupt the whole process group. # We don't use setpgrp, which is known to cause problems for kernels starting # certain interactive subprocesses, such as bash -i. if six.PY3: kwargs['start_new_session'] = True else: kwargs['preexec_fn'] = lambda: os.setsid() if not independent: env['JPY_PARENT_PID'] = str(os.getpid()) return kwargs
def launch_kernel(cmd, stdin=None, stdout=None, stderr=None, env=None, independent=False, cwd=None, **kw ): """ Launches a localhost kernel, binding to the specified ports. Parameters ---------- cmd : Popen list, A string of Python code that imports and executes a kernel entry point. stdin, stdout, stderr : optional (default None) Standards streams, as defined in subprocess.Popen. independent : bool, optional (default False) If set, the kernel process is guaranteed to survive if this process dies. If not set, an effort is made to ensure that the kernel is killed when this process dies. Note that in this case it is still good practice to kill kernels manually before exiting. cwd : path, optional The working dir of the kernel process (default: cwd of this process). Returns ------- Popen instance for the kernel subprocess """ # Popen will fail (sometimes with a deadlock) if stdin, stdout, and stderr # are invalid. Unfortunately, there is in general no way to detect whether # they are valid. The following two blocks redirect them to (temporary) # pipes in certain important cases. # If this process has been backgrounded, our stdin is invalid. Since there # is no compelling reason for the kernel to inherit our stdin anyway, we'll # place this one safe and always redirect. redirect_in = True _stdin = PIPE if stdin is None else stdin # If this process in running on pythonw, we know that stdin, stdout, and # stderr are all invalid. redirect_out = sys.executable.endswith('pythonw.exe') if redirect_out: blackhole = open(os.devnull, 'w') _stdout = blackhole if stdout is None else stdout _stderr = blackhole if stderr is None else stderr else: _stdout, _stderr = stdout, stderr env = env if (env is not None) else os.environ.copy() encoding = getdefaultencoding(prefer_stream=False) kwargs = dict( stdin=_stdin, stdout=_stdout, stderr=_stderr, cwd=cwd, env=env, ) # Spawn a kernel. if sys.platform == 'win32': # Popen on Python 2 on Windows cannot handle unicode args or cwd cmd = [ cast_bytes_py2(c, encoding) for c in cmd ] if cwd: cwd = cast_bytes_py2(cwd, sys.getfilesystemencoding() or 'ascii') kwargs['cwd'] = cwd from .win_interrupt import create_interrupt_event # Create a Win32 event for interrupting the kernel # and store it in an environment variable. interrupt_event = create_interrupt_event() env["JPY_INTERRUPT_EVENT"] = str(interrupt_event) # deprecated old env name: env["IPY_INTERRUPT_EVENT"] = env["JPY_INTERRUPT_EVENT"] try: from _winapi import DuplicateHandle, GetCurrentProcess, \ DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP except: from _subprocess import DuplicateHandle, GetCurrentProcess, \ DUPLICATE_SAME_ACCESS, CREATE_NEW_PROCESS_GROUP # Launch the kernel process if independent: kwargs['creationflags'] = CREATE_NEW_PROCESS_GROUP else: pid = GetCurrentProcess() handle = DuplicateHandle(pid, pid, pid, 0, True, # Inheritable by new processes. DUPLICATE_SAME_ACCESS) env['JPY_PARENT_PID'] = str(int(handle)) proc = Popen(cmd, **kwargs) # Attach the interrupt event to the Popen objet so it can be used later. proc.win32_interrupt_event = interrupt_event else: if independent: kwargs['preexec_fn'] = lambda: os.setsid() else: env['JPY_PARENT_PID'] = str(os.getpid()) proc = Popen(cmd, **kwargs) # Clean up pipes created to work around Popen bug. if redirect_in: if stdin is None: proc.stdin.close() return proc