Add kernel name to sessions REST API

Also, some refactoring so that the relationship between session, kernels
and notebooks is managed in the SessionManager, not in the HTTP
handlers.

IPython/html/notebookapp.py

@@ -658,7 +658,9 b' class NotebookApp(BaseIPythonApplication):'
         kls = import_item(self.notebook_manager_class)
         self.notebook_manager = kls(parent=self, log=self.log)
         kls = import_item(self.session_manager_class)
-        self.session_manager = kls(parent=self, log=self.log)
+        self.session_manager = kls(parent=self, log=self.log,
+                                   kernel_manager=self.kernel_manager,
+                                   notebook_manager=self.notebook_manager)
         kls = import_item(self.cluster_manager_class)
         self.cluster_manager = kls(parent=self, log=self.log)
         self.cluster_manager.update_profiles()

IPython/html/services/sessions/handlers.py

@@ -45,27 +45,28 b' class SessionRootHandler(IPythonHandler):'
         # Creates a new session
         #(unless a session already exists for the named nb)
         sm = self.session_manager
-        nbm = self.notebook_manager
-        km = self.kernel_manager
+
         model = self.get_json_body()
         if model is None:
             raise web.HTTPError(400, "No JSON data provided")
         try:
             name = model['notebook']['name']
         except KeyError:
-            raise web.HTTPError(400, "Missing field in JSON data: name")
+            raise web.HTTPError(400, "Missing field in JSON data: notebook.name")
         try:
             path = model['notebook']['path']
         except KeyError:
-            raise web.HTTPError(400, "Missing field in JSON data: path")
+            raise web.HTTPError(400, "Missing field in JSON data: notebook.path")
+        try:
+            kernel_name = model['kernel']['name']
+        except KeyError:
+            raise web.HTTPError(400, "Missing field in JSON data: kernel.name")
+
         # Check to see if session exists
         if sm.session_exists(name=name, path=path):
             model = sm.get_session(name=name, path=path)
         else:
-            # allow nbm to specify kernels cwd
-            kernel_path = nbm.get_kernel_path(name=name, path=path)
-            kernel_id = km.start_kernel(path=kernel_path)
-            model = sm.create_session(name=name, path=path, kernel_id=kernel_id)
+            model = sm.create_session(name=name, path=path, kernel_name=kernel_name)
         location = url_path_join(self.base_url, 'api', 'sessions', model['id'])
         self.set_header('Location', url_escape(location))
         self.set_status(201)
@@ -108,10 +109,7 b' class SessionHandler(IPythonHandler):'
     def delete(self, session_id):
         # Deletes the session with given session_id
         sm = self.session_manager
-        km = self.kernel_manager
-        session = sm.get_session(session_id=session_id)
         sm.delete_session(session_id)
-        km.shutdown_kernel(session['kernel']['id'])
         self.set_status(204)
         self.finish()
 

IPython/html/services/sessions/sessionmanager.py

@@ -23,6 +23,7 b' from tornado import web'
 
 from IPython.config.configurable import LoggingConfigurable
 from IPython.utils.py3compat import unicode_type
+from IPython.utils.traitlets import Instance
 
 #-----------------------------------------------------------------------------
 # Classes
@@ -30,6 +31,9 b' from IPython.utils.py3compat import unicode_type'
 
 class SessionManager(LoggingConfigurable):
     
+    kernel_manager = Instance('IPython.html.services.kernels.kernelmanager.MappingKernelManager')
+    notebook_manager = Instance('IPython.html.services.notebooks.nbmanager.NotebookManager', args=())
+    
     # Session database initialized below
     _cursor = None
     _connection = None
@@ -69,10 +73,15 b' class SessionManager(LoggingConfigurable):'
         "Create a uuid for a new session"
         return unicode_type(uuid.uuid4())
 
-    def create_session(self, name=None, path=None, kernel_id=None):
+    def create_session(self, name=None, path=None, kernel_name='python'):
         """Creates a session and returns its model"""
         session_id = self.new_session_id()
-        return self.save_session(session_id, name=name, path=path, kernel_id=kernel_id)
+        # allow nbm to specify kernels cwd
+        kernel_path = self.notebook_manager.get_kernel_path(name=name, path=path)
+        kernel_id = self.kernel_manager.start_kernel(path=kernel_path,
+                                                     kernel_name=kernel_name)
+        return self.save_session(session_id, name=name, path=path,
+                                 kernel_id=kernel_id)
 
     def save_session(self, session_id, name=None, path=None, kernel_id=None):
         """Saves the items for the session with the given session_id
@@ -170,8 +179,7 b' class SessionManager(LoggingConfigurable):'
         query = "UPDATE session SET %s WHERE session_id=?" % (', '.join(sets))
         self.cursor.execute(query, list(kwargs.values()) + [session_id])
 
-    @staticmethod
-    def row_factory(cursor, row):
+    def row_factory(self, cursor, row):
         """Takes sqlite database session row and turns it into a dictionary"""
         row = sqlite3.Row(cursor, row)
         model = {
@@ -180,9 +188,7 b' class SessionManager(LoggingConfigurable):'
                 'name': row['name'],
                 'path': row['path']
             },
-            'kernel': {
-                'id': row['kernel_id'],
-            }
+            'kernel': self.kernel_manager.kernel_model(row['kernel_id'])
         }
         return model
 
@@ -195,5 +201,6 b' class SessionManager(LoggingConfigurable):'
     def delete_session(self, session_id):
         """Deletes the row in the session database with given session_id"""
         # Check that session exists before deleting
-        self.get_session(session_id=session_id)
+        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,))

IPython/html/services/sessions/tests/test_sessionmanager.py

@@ -5,79 +5,101 b' from unittest import TestCase'
 from tornado import web
 
 from ..sessionmanager import SessionManager
+from IPython.html.services.kernels.kernelmanager import MappingKernelManager
+
+class DummyKernel(object):
+    def __init__(self, kernel_name='python'):
+        self.kernel_name = kernel_name
+
+class DummyMKM(MappingKernelManager):
+    """MappingKernelManager interface that doesn't start kernels, for testing"""
+    def __init__(self, *args, **kwargs):
+        super(DummyMKM, self).__init__(*args, **kwargs)
+        self.id_letters = iter(u'ABCDEFGHIJK')
+
+    def _new_id(self):
+        return next(self.id_letters)
+    
+    def start_kernel(self, kernel_id=None, path=None, kernel_name='python', **kwargs):
+        kernel_id = kernel_id or self._new_id()
+        self._kernels[kernel_id] = DummyKernel(kernel_name=kernel_name)
+        return kernel_id
+
+    def shutdown_kernel(self, kernel_id, now=False):
+        del self._kernels[kernel_id]
 
 class TestSessionManager(TestCase):
     
     def test_get_session(self):
-        sm = SessionManager()
-        session_id = sm.new_session_id()
-        sm.save_session(session_id=session_id, name='test.ipynb', path='/path/to/', kernel_id='5678')
+        sm = SessionManager(kernel_manager=DummyMKM())
+        session_id = sm.create_session(name='test.ipynb', path='/path/to/',
+                                       kernel_name='bar')['id']
         model = sm.get_session(session_id=session_id)
-        expected = {'id':session_id, 'notebook':{'name':u'test.ipynb', 'path': u'/path/to/'}, 'kernel':{'id':u'5678'}}
+        expected = {'id':session_id,
+                    'notebook':{'name':u'test.ipynb', 'path': u'/path/to/'},
+                    'kernel': {'id':u'A', 'name': 'bar'}}
         self.assertEqual(model, expected)
 
     def test_bad_get_session(self):
         # Should raise error if a bad key is passed to the database.
-        sm = SessionManager()
-        session_id = sm.new_session_id()
-        sm.save_session(session_id=session_id, name='test.ipynb', path='/path/to/', kernel_id='5678')
+        sm = SessionManager(kernel_manager=DummyMKM())
+        session_id = sm.create_session(name='test.ipynb', path='/path/to/',
+                                       kernel_name='foo')['id']
         self.assertRaises(TypeError, sm.get_session, bad_id=session_id) # Bad keyword
 
     def test_list_sessions(self):
-        sm = SessionManager()
-        session_id1 = sm.new_session_id()
-        session_id2 = sm.new_session_id()
-        session_id3 = sm.new_session_id()
-        sm.save_session(session_id=session_id1, name='test1.ipynb', path='/path/to/1/', kernel_id='5678')
-        sm.save_session(session_id=session_id2, name='test2.ipynb', path='/path/to/2/', kernel_id='5678')
-        sm.save_session(session_id=session_id3, name='test3.ipynb', path='/path/to/3/', kernel_id='5678')
+        sm = SessionManager(kernel_manager=DummyMKM())
+        sessions = [
+            sm.create_session(name='test1.ipynb', path='/path/to/1/', kernel_name='python'),
+            sm.create_session(name='test2.ipynb', path='/path/to/2/', kernel_name='python'),
+            sm.create_session(name='test3.ipynb', path='/path/to/3/', kernel_name='python'),
+        ]
         sessions = sm.list_sessions()
-        expected = [{'id':session_id1, 'notebook':{'name':u'test1.ipynb', 
-                    'path': u'/path/to/1/'}, 'kernel':{'id':u'5678'}},
-                    {'id':session_id2, 'notebook': {'name':u'test2.ipynb', 
-                    'path': u'/path/to/2/'}, 'kernel':{'id':u'5678'}},
-                    {'id':session_id3, 'notebook':{'name':u'test3.ipynb', 
-                    'path': u'/path/to/3/'}, 'kernel':{'id':u'5678'}}]
+        expected = [{'id':sessions[0]['id'], 'notebook':{'name':u'test1.ipynb', 
+                    'path': u'/path/to/1/'}, 'kernel':{'id':u'A', 'name':'python'}},
+                    {'id':sessions[1]['id'], 'notebook': {'name':u'test2.ipynb', 
+                    'path': u'/path/to/2/'}, 'kernel':{'id':u'B', 'name':'python'}},
+                    {'id':sessions[2]['id'], 'notebook':{'name':u'test3.ipynb', 
+                    'path': u'/path/to/3/'}, 'kernel':{'id':u'C', 'name':'python'}}]
         self.assertEqual(sessions, expected)
 
     def test_update_session(self):
-        sm = SessionManager()
-        session_id = sm.new_session_id()
-        sm.save_session(session_id=session_id, name='test.ipynb', path='/path/to/', kernel_id=None)
-        sm.update_session(session_id, kernel_id='5678')
+        sm = SessionManager(kernel_manager=DummyMKM())
+        session_id = sm.create_session(name='test.ipynb', path='/path/to/',
+                                       kernel_name='julia')['id']
         sm.update_session(session_id, name='new_name.ipynb')
         model = sm.get_session(session_id=session_id)
-        expected = {'id':session_id, 'notebook':{'name':u'new_name.ipynb', 'path': u'/path/to/'}, 'kernel':{'id':u'5678'}}
+        expected = {'id':session_id,
+                    'notebook':{'name':u'new_name.ipynb', 'path': u'/path/to/'},
+                    'kernel':{'id':u'A', 'name':'julia'}}
         self.assertEqual(model, expected)
     
     def test_bad_update_session(self):
         # try to update a session with a bad keyword ~ raise error
-        sm = SessionManager()
-        session_id = sm.new_session_id()
-        sm.save_session(session_id=session_id, name='test.ipynb', path='/path/to/', kernel_id='5678')
+        sm = SessionManager(kernel_manager=DummyMKM())
+        session_id = sm.create_session(name='test.ipynb', path='/path/to/',
+                                       kernel_name='ir')['id']
         self.assertRaises(TypeError, sm.update_session, session_id=session_id, bad_kw='test.ipynb') # Bad keyword
 
     def test_delete_session(self):
-        sm = SessionManager()
-        session_id1 = sm.new_session_id()
-        session_id2 = sm.new_session_id()
-        session_id3 = sm.new_session_id()
-        sm.save_session(session_id=session_id1, name='test1.ipynb', path='/path/to/1/', kernel_id='5678')
-        sm.save_session(session_id=session_id2, name='test2.ipynb', path='/path/to/2/', kernel_id='5678')
-        sm.save_session(session_id=session_id3, name='test3.ipynb', path='/path/to/3/', kernel_id='5678')
-        sm.delete_session(session_id2)
-        sessions = sm.list_sessions()
-        expected = [{'id':session_id1, 'notebook':{'name':u'test1.ipynb', 
-                    'path': u'/path/to/1/'}, 'kernel':{'id':u'5678'}},
-                    {'id':session_id3, 'notebook':{'name':u'test3.ipynb', 
-                    'path': u'/path/to/3/'}, 'kernel':{'id':u'5678'}}]
-        self.assertEqual(sessions, expected)
+        sm = SessionManager(kernel_manager=DummyMKM())
+        sessions = [
+            sm.create_session(name='test1.ipynb', path='/path/to/1/', kernel_name='python'),
+            sm.create_session(name='test2.ipynb', path='/path/to/2/', kernel_name='python'),
+            sm.create_session(name='test3.ipynb', path='/path/to/3/', kernel_name='python'),
+        ]
+        sm.delete_session(sessions[1]['id'])
+        new_sessions = sm.list_sessions()
+        expected = [{'id':sessions[0]['id'], 'notebook':{'name':u'test1.ipynb', 
+                    'path': u'/path/to/1/'}, 'kernel':{'id':u'A', 'name':'python'}},
+                    {'id':sessions[2]['id'], 'notebook':{'name':u'test3.ipynb', 
+                    'path': u'/path/to/3/'}, 'kernel':{'id':u'C', 'name':'python'}}]
+        self.assertEqual(new_sessions, expected)
 
     def test_bad_delete_session(self):
         # try to delete a session that doesn't exist ~ raise error
-        sm = SessionManager()
-        session_id = sm.new_session_id()
-        sm.save_session(session_id=session_id, name='test.ipynb', path='/path/to/', kernel_id='5678')
+        sm = SessionManager(kernel_manager=DummyMKM())
+        sm.create_session(name='test.ipynb', path='/path/to/', kernel_name='python')
         self.assertRaises(TypeError, sm.delete_session, bad_kwarg='23424') # Bad keyword
         self.assertRaises(web.HTTPError, sm.delete_session, session_id='23424') # nonexistant
 

IPython/html/services/sessions/tests/test_sessions_api.py

@@ -37,8 +37,9 b' class SessionAPI(object):'
     def get(self, id):
         return self._req('GET', id)
 
-    def create(self, name, path):
-        body = json.dumps({'notebook': {'name':name, 'path':path}})
+    def create(self, name, path, kernel_name='python'):
+        body = json.dumps({'notebook': {'name':name, 'path':path},
+                           'kernel': {'name': kernel_name}})
         return self._req('POST', '', body)
 
     def modify(self, id, name, path):