|
|
"""A base class session manager."""
|
|
|
|
|
|
# Copyright (c) IPython Development Team.
|
|
|
# Distributed under the terms of the Modified BSD License.
|
|
|
|
|
|
import uuid
|
|
|
import sqlite3
|
|
|
|
|
|
from tornado import web
|
|
|
|
|
|
from IPython.config.configurable import LoggingConfigurable
|
|
|
from IPython.utils.py3compat import unicode_type
|
|
|
from IPython.utils.traitlets import Instance
|
|
|
|
|
|
|
|
|
class SessionManager(LoggingConfigurable):
|
|
|
|
|
|
kernel_manager = Instance('IPython.html.services.kernels.kernelmanager.MappingKernelManager')
|
|
|
contents_manager = Instance('IPython.html.services.contents.manager.ContentsManager')
|
|
|
|
|
|
# Session database initialized below
|
|
|
_cursor = None
|
|
|
_connection = None
|
|
|
_columns = {'session_id', 'path', 'kernel_id'}
|
|
|
|
|
|
@property
|
|
|
def cursor(self):
|
|
|
"""Start a cursor and create a database called 'session'"""
|
|
|
if self._cursor is None:
|
|
|
self._cursor = self.connection.cursor()
|
|
|
self._cursor.execute("""CREATE TABLE session
|
|
|
(session_id, path, kernel_id)""")
|
|
|
return self._cursor
|
|
|
|
|
|
@property
|
|
|
def connection(self):
|
|
|
"""Start a database connection"""
|
|
|
if self._connection is None:
|
|
|
self._connection = sqlite3.connect(':memory:')
|
|
|
self._connection.row_factory = sqlite3.Row
|
|
|
return self._connection
|
|
|
|
|
|
def __del__(self):
|
|
|
"""Close connection once SessionManager closes"""
|
|
|
self.cursor.close()
|
|
|
|
|
|
def session_exists(self, path):
|
|
|
"""Check to see if the session for a given notebook exists"""
|
|
|
self.cursor.execute("SELECT * FROM session WHERE path=?", (path,))
|
|
|
reply = self.cursor.fetchone()
|
|
|
if reply is None:
|
|
|
return False
|
|
|
else:
|
|
|
return True
|
|
|
|
|
|
def new_session_id(self):
|
|
|
"Create a uuid for a new session"
|
|
|
return unicode_type(uuid.uuid4())
|
|
|
|
|
|
def create_session(self, path=None, kernel_name=None):
|
|
|
"""Creates a session and returns its model"""
|
|
|
session_id = self.new_session_id()
|
|
|
# allow nbm to specify kernels cwd
|
|
|
kernel_path = self.contents_manager.get_kernel_path(path=path)
|
|
|
kernel_id = self.kernel_manager.start_kernel(path=kernel_path,
|
|
|
kernel_name=kernel_name)
|
|
|
return self.save_session(session_id, path=path,
|
|
|
kernel_id=kernel_id)
|
|
|
|
|
|
def save_session(self, session_id, path=None, kernel_id=None):
|
|
|
"""Saves the items for the session with the given session_id
|
|
|
|
|
|
Given a session_id (and any other of the arguments), this method
|
|
|
creates a row in the sqlite session database that holds the information
|
|
|
for a session.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
session_id : str
|
|
|
uuid for the session; this method must be given a session_id
|
|
|
path : str
|
|
|
the path for the given notebook
|
|
|
kernel_id : str
|
|
|
a uuid for the kernel associated with this session
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
model : dict
|
|
|
a dictionary of the session model
|
|
|
"""
|
|
|
self.cursor.execute("INSERT INTO session VALUES (?,?,?)",
|
|
|
(session_id, path, kernel_id)
|
|
|
)
|
|
|
return self.get_session(session_id=session_id)
|
|
|
|
|
|
def get_session(self, **kwargs):
|
|
|
"""Returns the model for a particular session.
|
|
|
|
|
|
Takes a keyword argument and searches for the value in the session
|
|
|
database, then returns the rest of the session's info.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
**kwargs : keyword argument
|
|
|
must be given one of the keywords and values from the session database
|
|
|
(i.e. session_id, path, kernel_id)
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
model : dict
|
|
|
returns a dictionary that includes all the information from the
|
|
|
session described by the kwarg.
|
|
|
"""
|
|
|
if not kwargs:
|
|
|
raise TypeError("must specify a column to query")
|
|
|
|
|
|
conditions = []
|
|
|
for column in kwargs.keys():
|
|
|
if column not in self._columns:
|
|
|
raise TypeError("No such column: %r", column)
|
|
|
conditions.append("%s=?" % column)
|
|
|
|
|
|
query = "SELECT * FROM session WHERE %s" % (' AND '.join(conditions))
|
|
|
|
|
|
self.cursor.execute(query, list(kwargs.values()))
|
|
|
try:
|
|
|
row = self.cursor.fetchone()
|
|
|
except KeyError:
|
|
|
# The kernel is missing, so the session just got deleted.
|
|
|
row = None
|
|
|
|
|
|
if row is None:
|
|
|
q = []
|
|
|
for key, value in kwargs.items():
|
|
|
q.append("%s=%r" % (key, value))
|
|
|
|
|
|
raise web.HTTPError(404, u'Session not found: %s' % (', '.join(q)))
|
|
|
|
|
|
return self.row_to_model(row)
|
|
|
|
|
|
def update_session(self, session_id, **kwargs):
|
|
|
"""Updates the values in the session database.
|
|
|
|
|
|
Changes the values of the session with the given session_id
|
|
|
with the values from the keyword arguments.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
session_id : str
|
|
|
a uuid that identifies a session in the sqlite3 database
|
|
|
**kwargs : str
|
|
|
the key must correspond to a column title in session database,
|
|
|
and the value replaces the current value in the session
|
|
|
with session_id.
|
|
|
"""
|
|
|
self.get_session(session_id=session_id)
|
|
|
|
|
|
if not kwargs:
|
|
|
# no changes
|
|
|
return
|
|
|
|
|
|
sets = []
|
|
|
for column in kwargs.keys():
|
|
|
if column not in self._columns:
|
|
|
raise TypeError("No such column: %r" % column)
|
|
|
sets.append("%s=?" % column)
|
|
|
query = "UPDATE session SET %s WHERE session_id=?" % (', '.join(sets))
|
|
|
self.cursor.execute(query, list(kwargs.values()) + [session_id])
|
|
|
|
|
|
def row_to_model(self, row):
|
|
|
"""Takes sqlite database session row and turns it into a dictionary"""
|
|
|
if row['kernel_id'] not in self.kernel_manager:
|
|
|
# The kernel was killed or died without deleting the session.
|
|
|
# We can't use delete_session here because that tries to find
|
|
|
# and shut down the kernel.
|
|
|
self.cursor.execute("DELETE FROM session WHERE session_id=?",
|
|
|
(row['session_id'],))
|
|
|
raise KeyError
|
|
|
|
|
|
model = {
|
|
|
'id': row['session_id'],
|
|
|
'notebook': {
|
|
|
'path': row['path']
|
|
|
},
|
|
|
'kernel': self.kernel_manager.kernel_model(row['kernel_id'])
|
|
|
}
|
|
|
return model
|
|
|
|
|
|
def list_sessions(self):
|
|
|
"""Returns a list of dictionaries containing all the information from
|
|
|
the session database"""
|
|
|
c = self.cursor.execute("SELECT * FROM session")
|
|
|
result = []
|
|
|
# We need to use fetchall() here, because row_to_model can delete rows,
|
|
|
# which messes up the cursor if we're iterating over rows.
|
|
|
for row in c.fetchall():
|
|
|
try:
|
|
|
result.append(self.row_to_model(row))
|
|
|
except KeyError:
|
|
|
pass
|
|
|
return result
|
|
|
|
|
|
def delete_session(self, session_id):
|
|
|
"""Deletes the row in the session database with given session_id"""
|
|
|
# Check that session exists before deleting
|
|
|
session = self.get_session(session_id=session_id)
|
|
|
self.kernel_manager.shutdown_kernel(session['kernel']['id'])
|
|
|
self.cursor.execute("DELETE FROM session WHERE session_id=?", (session_id,))
|
|
|
|
