"""A kernel manager for multiple kernels.""" #----------------------------------------------------------------------------- # Copyright (C) 2011 The IPython Development Team # # Distributed under the terms of the BSD License. The full license is in # the file COPYING.txt, distributed as part of this software. #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Imports #----------------------------------------------------------------------------- import signal import sys import uuid import zmq from IPython.config.configurable import LoggingConfigurable from IPython.zmq.ipkernel import launch_kernel from IPython.utils.traitlets import Instance, Dict #----------------------------------------------------------------------------- # Classes #----------------------------------------------------------------------------- class DuplicateKernelError(Exception): pass class KernelManager(LoggingConfigurable): """A class for managing multiple kernels.""" context = Instance('zmq.Context') def _context_default(self): return zmq.Context.instance() _kernels = Dict() @property def kernel_ids(self): """Return a list of the kernel ids of the active kernels.""" return self._kernels.keys() def __len__(self): """Return the number of running kernels.""" return len(self.kernel_ids) def __contains__(self, kernel_id): if kernel_id in self.kernel_ids: return True else: return False def start_kernel(self, **kwargs): """Start a new kernel.""" kernel_id = str(uuid.uuid4()) (process, shell_port, iopub_port, stdin_port, hb_port) = launch_kernel(**kwargs) # Store the information for contacting the kernel. This assumes the kernel is # running on localhost. d = dict( process = process, stdin_port = stdin_port, iopub_port = iopub_port, shell_port = shell_port, hb_port = hb_port, ip = '127.0.0.1' ) self._kernels[kernel_id] = d return kernel_id def kill_kernel(self, kernel_id): """Kill a kernel by its kernel uuid. Parameters ========== kernel_id : uuid The id of the kernel to kill. """ kernel_process = self.get_kernel_process(kernel_id) if kernel_process is not None: # Attempt to kill the kernel. try: kernel_process.kill() except OSError, e: # In Windows, we will get an Access Denied error if the process # has already terminated. Ignore it. if not (sys.platform == 'win32' and e.winerror == 5): raise del self._kernels[kernel_id] def interrupt_kernel(self, kernel_id): """Interrupt (SIGINT) the kernel by its uuid. Parameters ========== kernel_id : uuid The id of the kernel to interrupt. """ kernel_process = self.get_kernel_process(kernel_id) if kernel_process is not None: if sys.platform == 'win32': from parentpoller import ParentPollerWindows as Poller Poller.send_interrupt(kernel_process.win32_interrupt_event) else: kernel_process.send_signal(signal.SIGINT) def signal_kernel(self, kernel_id, signum): """ Sends a signal to the kernel by its uuid. Note that since only SIGTERM is supported on Windows, this function is only useful on Unix systems. Parameters ========== kernel_id : uuid The id of the kernel to signal. """ kernel_process = self.get_kernel_process(kernel_id) if kernel_process is not None: kernel_process.send_signal(signum) def get_kernel_process(self, kernel_id): """Get the process object for a kernel by its uuid. Parameters ========== kernel_id : uuid The id of the kernel. """ d = self._kernels.get(kernel_id) if d is not None: return d['process'] else: raise KeyError("Kernel with id not found: %s" % kernel_id) def get_kernel_ports(self, kernel_id): """Return a dictionary of ports for a kernel. Parameters ========== kernel_id : uuid The id of the kernel. Returns ======= port_dict : dict A dict of key, value pairs where the keys are the names (stdin_port,iopub_port,shell_port) and the values are the integer port numbers for those channels. """ d = self._kernels.get(kernel_id) if d is not None: dcopy = d.copy() dcopy.pop('process') dcopy.pop('ip') return dcopy else: raise KeyError("Kernel with id not found: %s" % kernel_id) def get_kernel_ip(self, kernel_id): """Return ip address for a kernel. Parameters ========== kernel_id : uuid The id of the kernel. Returns ======= ip : str The ip address of the kernel. """ d = self._kernels.get(kernel_id) if d is not None: return d['ip'] else: raise KeyError("Kernel with id not found: %s" % kernel_id) def create_session_manager(self, kernel_id): """Create a new session manager for a kernel by its uuid.""" from sessionmanager import SessionManager return SessionManager( kernel_id=kernel_id, kernel_manager=self, config=self.config, context=self.context, log=self.log )