add error catching to kernel manager

also, adding further tests to kernel manager

IPython/html/services/kernels/handlers.py

@@ -1,186 +1,191 b''
 """Tornado handlers for the notebook.
 
 Authors:
 
 * Brian Granger
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import logging
 from tornado import web
 
 from zmq.utils import jsonapi
 
 from IPython.utils.jsonutil import date_default
 
-from ...base.handlers import IPythonHandler
+from ...base.handlers import IPythonHandler, json_errors
 from ...base.zmqhandlers import AuthenticatedZMQStreamHandler
 
 #-----------------------------------------------------------------------------
 # Kernel handlers
 #-----------------------------------------------------------------------------
 
 
 class MainKernelHandler(IPythonHandler):
 
     @web.authenticated
+    @json_errors
     def get(self):
         km = self.kernel_manager
-        self.finish(jsonapi.dumps(km.list_kernels()))
+        self.finish(jsonapi.dumps(km.list_kernels(self.ws_url)))
 
     @web.authenticated
+    @json_errors
     def post(self):
         km = self.kernel_manager
         kernel_id = km.start_kernel()
         model = km.kernel_model(kernel_id, self.ws_url)
         self.set_header('Location', '{0}kernels/{1}'.format(self.base_kernel_url, kernel_id))
         self.finish(jsonapi.dumps(model))
 
 
 class KernelHandler(IPythonHandler):
 
     SUPPORTED_METHODS = ('DELETE', 'GET')
 
     @web.authenticated
+    @json_errors
     def get(self, kernel_id):
         km = self.kernel_manager
         model = km.kernel_model(kernel_id, self.ws_url)
         self.finish(jsonapi.dumps(model))
 
     @web.authenticated
+    @json_errors
     def delete(self, kernel_id):
         km = self.kernel_manager
         km.shutdown_kernel(kernel_id)
         self.set_status(204)
         self.finish()
 
 
 class KernelActionHandler(IPythonHandler):
 
     @web.authenticated
+    @json_errors
     def post(self, kernel_id, action):
         km = self.kernel_manager
         if action == 'interrupt':
             km.interrupt_kernel(kernel_id)
             self.set_status(204)
         if action == 'restart':
             km.restart_kernel(kernel_id)
             model = km.kernel_model(kernel_id, self.ws_url)
             self.set_header('Location', '{0}api/kernels/{1}'.format(self.base_kernel_url, kernel_id))
             self.write(jsonapi.dumps(model))
         self.finish()
 
 
 class ZMQChannelHandler(AuthenticatedZMQStreamHandler):
     
     def create_stream(self):
         km = self.kernel_manager
         meth = getattr(km, 'connect_%s' % self.channel)
         self.zmq_stream = meth(self.kernel_id, identity=self.session.bsession)
     
     def initialize(self, *args, **kwargs):
         self.zmq_stream = None
     
     def on_first_message(self, msg):
         try:
             super(ZMQChannelHandler, self).on_first_message(msg)
         except web.HTTPError:
             self.close()
             return
         try:
             self.create_stream()
         except web.HTTPError:
             # WebSockets don't response to traditional error codes so we
             # close the connection.
             if not self.stream.closed():
                 self.stream.close()
             self.close()
         else:
             self.zmq_stream.on_recv(self._on_zmq_reply)
 
     def on_message(self, msg):
         msg = jsonapi.loads(msg)
         self.session.send(self.zmq_stream, msg)
 
     def on_close(self):
         # This method can be called twice, once by self.kernel_died and once
         # from the WebSocket close event. If the WebSocket connection is
         # closed before the ZMQ streams are setup, they could be None.
         if self.zmq_stream is not None and not self.zmq_stream.closed():
             self.zmq_stream.on_recv(None)
             self.zmq_stream.close()
 
 
 class IOPubHandler(ZMQChannelHandler):
     channel = 'iopub'
     
     def create_stream(self):
         super(IOPubHandler, self).create_stream()
         km = self.kernel_manager
         km.add_restart_callback(self.kernel_id, self.on_kernel_restarted)
         km.add_restart_callback(self.kernel_id, self.on_restart_failed, 'dead')
     
     def on_close(self):
         km = self.kernel_manager
         if self.kernel_id in km:
             km.remove_restart_callback(
                 self.kernel_id, self.on_kernel_restarted,
             )
             km.remove_restart_callback(
                 self.kernel_id, self.on_restart_failed, 'dead',
             )
         super(IOPubHandler, self).on_close()
     
     def _send_status_message(self, status):
         msg = self.session.msg("status",
             {'execution_state': status}
         )
         self.write_message(jsonapi.dumps(msg, default=date_default))
 
     def on_kernel_restarted(self):
         logging.warn("kernel %s restarted", self.kernel_id)
         self._send_status_message('restarting')
 
     def on_restart_failed(self):
         logging.error("kernel %s restarted failed!", self.kernel_id)
         self._send_status_message('dead')
     
     def on_message(self, msg):
         """IOPub messages make no sense"""
         pass
 
 
 class ShellHandler(ZMQChannelHandler):
     channel = 'shell'
 
 
 class StdinHandler(ZMQChannelHandler):
     channel = 'stdin'
 
 
 #-----------------------------------------------------------------------------
 # URL to handler mappings
 #-----------------------------------------------------------------------------
 
 
 _kernel_id_regex = r"(?P<kernel_id>\w+-\w+-\w+-\w+-\w+)"
 _kernel_action_regex = r"(?P<action>restart|interrupt)"
 
 default_handlers = [
     (r"/api/kernels", MainKernelHandler),
     (r"/api/kernels/%s" % _kernel_id_regex, KernelHandler),
     (r"/api/kernels/%s/%s" % (_kernel_id_regex, _kernel_action_regex), KernelActionHandler),
     (r"/api/kernels/%s/iopub" % _kernel_id_regex, IOPubHandler),
     (r"/api/kernels/%s/shell" % _kernel_id_regex, ShellHandler),
     (r"/api/kernels/%s/stdin" % _kernel_id_regex, StdinHandler)
 ]

IPython/html/services/kernels/kernelmanager.py

@@ -1,90 +1,95 b''
 """A kernel manager relating notebooks and kernels
 
 Authors:
 
 * Brian Granger
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2013  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 from tornado import web
 
 from IPython.kernel.multikernelmanager import MultiKernelManager
 from IPython.utils.traitlets import (
     Dict, List, Unicode,
 )
 
 #-----------------------------------------------------------------------------
 # Classes
 #-----------------------------------------------------------------------------
 
 
 class MappingKernelManager(MultiKernelManager):
     """A KernelManager that handles notebook mapping and HTTP error handling"""
 
     def _kernel_manager_class_default(self):
         return "IPython.kernel.ioloop.IOLoopKernelManager"
 
     kernel_argv = List(Unicode)
 
     #-------------------------------------------------------------------------
     # Methods for managing kernels and sessions
     #-------------------------------------------------------------------------
 
     def _handle_kernel_died(self, kernel_id):
         """notice that a kernel died"""
         self.log.warn("Kernel %s died, removing from map.", kernel_id)
         self.remove_kernel(kernel_id)
 
     def start_kernel(self, kernel_id=None, **kwargs):
         """Start a kernel for a session an return its kernel_id.
 
         Parameters
         ----------
         kernel_id : uuid
             The uuid to associate the new kernel with. If this
             is not None, this kernel will be persistent whenever it is 
             requested.
         """
         if kernel_id is None:
             kwargs['extra_arguments'] = self.kernel_argv
             kernel_id = super(MappingKernelManager, self).start_kernel(**kwargs)
             self.log.info("Kernel started: %s" % kernel_id)
             self.log.debug("Kernel args: %r" % kwargs)
             # register callback for failed auto-restart
             self.add_restart_callback(kernel_id,
                 lambda : self._handle_kernel_died(kernel_id),
                 'dead',
             )
         else:
             self.log.info("Using existing kernel: %s" % kernel_id)
         return kernel_id
 
     def shutdown_kernel(self, kernel_id, now=False):
         """Shutdown a kernel by kernel_id"""
         super(MappingKernelManager, self).shutdown_kernel(kernel_id, now=now)
 
     def kernel_model(self, kernel_id, ws_url):
         """Return a dictionary of kernel information described in the
         JSON standard model."""
         model = {"id":kernel_id, "ws_url": ws_url}
         return model
 
-    def list_kernels(self):
+    def list_kernels(self, ws_url):
         """Returns a list of kernel_id's of kernels running."""
-        return super(MappingKernelManager, self).list_kernel_ids()
+        kernels = []
+        kernel_ids = super(MappingKernelManager, self).list_kernel_ids()
+        for kernel_id in kernel_ids:
+            model = self.kernel_model(kernel_id, ws_url)
+            kernels.append(model)
+        return kernels
 
     # override _check_kernel_id to raise 404 instead of KeyError
     def _check_kernel_id(self, kernel_id):
         """Check a that a kernel_id exists and raise 404 if not."""
         if kernel_id not in self:
             raise web.HTTPError(404, u'Kernel does not exist: %s' % kernel_id)

IPython/html/services/kernels/tests/test_kernels_api.py

@@ -1,54 +1,54 b''
 """Test the kernels service API."""
 
 
 import os
 import sys
 import json
 
 import requests
 
 from IPython.html.utils import url_path_join
 from IPython.html.tests.launchnotebook import NotebookTestBase
 
 
 class KernelAPITest(NotebookTestBase):
     """Test the kernels web service API"""
 
     def base_url(self):
         return url_path_join(super(KernelAPITest,self).base_url(), 'api/kernels')
 
     def mkkernel(self):
         r = requests.post(self.base_url())
         return r.json()
 
     def test__no_kernels(self):
         """Make sure there are no kernels running at the start"""
         url = self.base_url()
         r = requests.get(url)
         self.assertEqual(r.json(), [])
 
     def test_main_kernel_handler(self):
         # POST request
         r = requests.post(self.base_url())
         data = r.json()
         assert isinstance(data, dict)
 
         # GET request
         r = requests.get(self.base_url())
         assert isinstance(r.json(), list)
-        self.assertEqual(r.json()[0], data['id'])
+        self.assertEqual(r.json()[0]['id'], data['id'])
 
     def test_kernel_handler(self):
         # GET kernel with id
         data = self.mkkernel()
         url = self.base_url() +'/' + data['id']
         r = requests.get(url)
         assert isinstance(r.json(), dict)
         self.assertIn('id', r.json())
         self.assertEqual(r.json()['id'], data['id'])
         
         # DELETE kernel with id
         r = requests.delete(url)
         self.assertEqual(r.status_code, 204)
         r = requests.get(self.base_url())
         self.assertEqual(r.json(), [])

IPython/html/services/notebooks/filenbmanager.py

@@ -1,350 +1,350 b''
 """A notebook manager that uses the local file system for storage.
 
 Authors:
 
 * Brian Granger
 * Zach Sailer
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2011  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import datetime
 import io
 import os
 import glob
 import shutil
 
 from unicodedata import normalize
 
 from tornado import web
 
 from .nbmanager import NotebookManager
 from IPython.nbformat import current
 from IPython.utils.traitlets import Unicode, Dict, Bool, TraitError
 from IPython.utils import tz
 
 #-----------------------------------------------------------------------------
 # Classes
 #-----------------------------------------------------------------------------
 
 class FileNotebookManager(NotebookManager):
     
     save_script = Bool(False, config=True,
         help="""Automatically create a Python script when saving the notebook.
         
         For easier use of import, %run and %load across notebooks, a
         <notebook-name>.py script will be created next to any
         <notebook-name>.ipynb on each save.  This can also be set with the
         short `--script` flag.
         """
     )
     
     checkpoint_dir = Unicode(config=True,
         help="""The location in which to keep notebook checkpoints
         
         By default, it is notebook-dir/.ipynb_checkpoints
         """
     )
     def _checkpoint_dir_default(self):
         return os.path.join(self.notebook_dir, '.ipynb_checkpoints')
     
     def _checkpoint_dir_changed(self, name, old, new):
         """do a bit of validation of the checkpoint dir"""
         if not os.path.isabs(new):
             # If we receive a non-absolute path, make it absolute.
             abs_new = os.path.abspath(new)
             self.checkpoint_dir = abs_new
             return
         if os.path.exists(new) and not os.path.isdir(new):
             raise TraitError("checkpoint dir %r is not a directory" % new)
         if not os.path.exists(new):
             self.log.info("Creating checkpoint dir %s", new)
             try:
                 os.mkdir(new)
             except:
                 raise TraitError("Couldn't create checkpoint dir %r" % new)
 
     def get_notebook_names(self, path='/'):
         """List all notebook names in the notebook dir and path."""
         names = glob.glob(self.get_os_path('*'+self.filename_ext, path))
         names = [os.path.basename(name)
                  for name in names]
         return names
 
     def increment_filename(self, basename, path='/'):
         """Return a non-used filename of the form basename<int>."""
         i = 0
         while True:
             name = u'%s%i.ipynb' % (basename,i)
             os_path = self.get_os_path(name, path)
             if not os.path.isfile(os_path):
                 break
             else:
                 i = i+1
         return name
 
     def notebook_exists(self, name, path='/'):
         """Returns a True if the notebook exists. Else, returns False.
 
         Parameters
         ----------
         name : string
             The name of the notebook you are checking.
         path : string
             The relative path to the notebook (with '/' as separator)
 
         Returns
         -------
         bool
         """
         path = self.get_os_path(name, path='/')
         return os.path.isfile(path)
 
     def list_notebooks(self, path):
         """Returns a list of dictionaries that are the standard model
         for all notebooks in the relative 'path'.
         
         Parameters
         ----------
         path : str
             the URL path that describes the relative path for the
             listed notebooks
         
         Returns
         -------
         notebooks : list of dicts
             a list of the notebook models without 'content'
         """
         notebook_names = self.get_notebook_names(path)
         notebooks = []
         for name in notebook_names:
             model = self.get_notebook_model(name, path, content=False)
             notebooks.append(model)
         notebooks = sorted(notebooks, key=lambda item: item['name'])
         return notebooks
 
     def get_notebook_model(self, name, path='/', content=True):
         """ Takes a path and name for a notebook and returns it's model
         
         Parameters
         ----------
         name : str
             the name of the notebook
         path : str
             the URL path that describes the relative path for
             the notebook
             
         Returns
         -------
         model : dict
             the notebook model. If contents=True, returns the 'contents' 
             dict in the model as well.
         """
         os_path = self.get_os_path(name, path)
         if not os.path.isfile(os_path):
             raise web.HTTPError(404, u'Notebook does not exist: %s' % name)
         info = os.stat(os_path)
         last_modified = tz.utcfromtimestamp(info.st_mtime)
         # Create the notebook model.
         model ={}
         model['name'] = name
         model['path'] = path
         model['last_modified'] = last_modified
         if content is True:
             with open(os_path, 'r') as f:
                 try:
                     nb = current.read(f, u'json')
                 except Exception as e:
                     raise web.HTTPError(400, u"Unreadable Notebook: %s %s" % (os_path, e))
             model['content'] = nb
         return model
 
     def save_notebook_model(self, model, name, path='/'):
         """Save the notebook model and return the model with no content."""
 
         if 'content' not in model:
             raise web.HTTPError(400, u'No notebook JSON data provided')
 
         new_path = model.get('path', path)
         new_name = model.get('name', name)
 
         if path != new_path or name != new_name:
             self.rename_notebook(name, path, new_name, new_path)
 
         # Save the notebook file
         os_path = self.get_os_path(new_name, new_path)
         nb = current.to_notebook_json(model['content'])
         if 'name' in nb['metadata']:
             nb['metadata']['name'] = u''
         try:
             self.log.debug("Autosaving notebook %s", os_path)
             with open(os_path, 'w') as f:
                 current.write(nb, f, u'json')
         except Exception as e:
             raise web.HTTPError(400, u'Unexpected error while autosaving notebook: %s %s' % (os_path, e))
 
         # Save .py script as well
         if self.save_script:
             py_path = os.path.splitext(os_path)[0] + '.py'
             self.log.debug("Writing script %s", py_path)
             try:
                 with io.open(py_path, 'w', encoding='utf-8') as f:
                     current.write(model, f, u'py')
             except Exception as e:
                 raise web.HTTPError(400, u'Unexpected error while saving notebook as script: %s %s' % (py_path, e))
 
         model = self.get_notebook_model(name, path, content=False)
         return model
 
     def update_notebook_model(self, model, name, path='/'):
         """Update the notebook's path and/or name"""
         new_name = model.get('name', name)
         new_path = model.get('path', path)
         if path != new_path or name != new_name:
             self.rename_notebook(name, path, new_name, new_path)
         model = self.get_notebook_model(new_name, new_path, content=False)
         return model
 
     def delete_notebook_model(self, name, path='/'):
         """Delete notebook by name and path."""
         os_path = self.get_os_path(name, path)
         if not os.path.isfile(os_path):
             raise web.HTTPError(404, u'Notebook does not exist: %s' % os_path)
         
         # clear checkpoints
         for checkpoint in self.list_checkpoints(name, path):
             checkpoint_id = checkpoint['checkpoint_id']
             cp_path = self.get_checkpoint_path(checkpoint_id, name, path)
             if os.path.isfile(cp_path):
                 self.log.debug("Unlinking checkpoint %s", cp_path)
                 os.unlink(cp_path)
         
-        self.log.debug("Unlinking notebook %s", nb_path)
-        os.unlink(nb_path)
+        self.log.debug("Unlinking notebook %s", os_path)
+        os.unlink(os_path)
 
     def rename_notebook(self, old_name, old_path, new_name, new_path):
         """Rename a notebook."""
         if new_name == old_name and new_path == old_path:
             return
         
         new_os_path = self.get_os_path(new_name, new_path)
         old_os_path = self.get_os_path(old_name, old_path)
 
         # Should we proceed with the move?
         if os.path.isfile(new_os_path):
             raise web.HTTPError(409, u'Notebook with name already exists: ' % new_os_path)
         if self.save_script:
             old_py_path = os.path.splitext(old_os_path)[0] + '.py'
             new_py_path = os.path.splitext(new_os_path)[0] + '.py'
             if os.path.isfile(new_py_path):
                 raise web.HTTPError(409, u'Python script with name already exists: %s' % new_py_path)
 
         # Move the notebook file
         try:
             os.rename(old_os_path, new_os_path)
         except Exception as e:
             raise web.HTTPError(400, u'Unknown error renaming notebook: %s %s' % (old_os_path, e))
 
         # Move the checkpoints
         old_checkpoints = self.list_checkpoints(old_name, old_path)
         for cp in old_checkpoints:
             checkpoint_id = cp['checkpoint_id']
             old_cp_path = self.get_checkpoint_path(checkpoint_id, old_name, path)
             new_cp_path = self.get_checkpoint_path(checkpoint_id, new_name, path)
             if os.path.isfile(old_cp_path):
                 self.log.debug("Renaming checkpoint %s -> %s", old_cp_path, new_cp_path)
                 os.rename(old_cp_path, new_cp_path)
 
         # Move the .py script
         if self.save_script:
             os.rename(old_py_path, new_py_path)
   
     # Checkpoint-related utilities
     
     def get_checkpoint_path(self, checkpoint_id, name, path='/'):
         """find the path to a checkpoint"""
         filename = u"{name}-{checkpoint_id}{ext}".format(
             name=name,
             checkpoint_id=checkpoint_id,
             ext=self.filename_ext,
         )
         cp_path = os.path.join(path, self.checkpoint_dir, filename)
         return cp_path
 
     def get_checkpoint_model(self, checkpoint_id, name, path='/'):
         """construct the info dict for a given checkpoint"""
         cp_path = self.get_checkpoint_path(checkpoint_id, name, path)
         stats = os.stat(cp_path)
         last_modified = tz.utcfromtimestamp(stats.st_mtime)
         info = dict(
             checkpoint_id = checkpoint_id,
             last_modified = last_modified,
         )
         return info
         
     # public checkpoint API
     
     def create_checkpoint(self, name, path='/'):
         """Create a checkpoint from the current state of a notebook"""
         nb_path = self.get_os_path(name, path)
         # only the one checkpoint ID:
         checkpoint_id = u"checkpoint"
         cp_path = self.get_checkpoint_path(checkpoint_id, name, path)
         self.log.debug("creating checkpoint for notebook %s", name)
         if not os.path.exists(self.checkpoint_dir):
             os.mkdir(self.checkpoint_dir)
         shutil.copy2(nb_path, cp_path)
         
         # return the checkpoint info
         return self.get_checkpoint_model(checkpoint_id, name, path)
     
     def list_checkpoints(self, name, path='/'):
         """list the checkpoints for a given notebook
         
         This notebook manager currently only supports one checkpoint per notebook.
         """
         checkpoint_id = "checkpoint"
         path = self.get_checkpoint_path(checkpoint_id, name, path)
         if not os.path.exists(path):
             return []
         else:
             return [self.get_checkpoint_model(checkpoint_id, name, path)]
         
     
     def restore_checkpoint(self, checkpoint_id, name, path='/'):
         """restore a notebook to a checkpointed state"""
         self.log.info("restoring Notebook %s from checkpoint %s", name, checkpoint_id)
         nb_path = self.get_os_path(name, path)
         cp_path = self.get_checkpoint_path(checkpoint_id, name, path)
         if not os.path.isfile(cp_path):
             self.log.debug("checkpoint file does not exist: %s", cp_path)
             raise web.HTTPError(404,
                 u'Notebook checkpoint does not exist: %s-%s' % (name, checkpoint_id)
             )
         # ensure notebook is readable (never restore from an unreadable notebook)
         with file(cp_path, 'r') as f:
             nb = current.read(f, u'json')
         shutil.copy2(cp_path, nb_path)
         self.log.debug("copying %s -> %s", cp_path, nb_path)
     
     def delete_checkpoint(self, checkpoint_id, name, path='/'):
         """delete a notebook's checkpoint"""
         cp_path = self.get_checkpoint_path(checkpoint_id, name, path)
         if not os.path.isfile(cp_path):
             raise web.HTTPError(404,
                 u'Notebook checkpoint does not exist: %s%s-%s' % (path, name, checkpoint_id)
             )
         self.log.debug("unlinking %s", cp_path)
         os.unlink(cp_path)
     
     def info_string(self):
         return "Serving notebooks from local directory: %s" % self.notebook_dir