initialize Application in background thread

rather than initializing in main and starting in background, which seemed to cause occasional issues.

Also fix checking for dead notebook, which is no longer a subprocess.

notebook/services/sessions/tests/test_sessionmanager.py

@@ -56,13 +56,10 @@ class TestSessionManager(TestCase):
     def create_session(self, **kwargs):
         return self.create_sessions(kwargs)[0]
     
-    def get_session(self, **kwargs):
-        return self.loop.run_sync(lambda : self.sm.get_session(**kwargs))
-    
     def test_get_session(self):
         sm = self.sm
         session_id = self.create_session(path='/path/to/test.ipynb', kernel_name='bar')['id']
-        model = self.get_session(session_id=session_id)
+        model = sm.get_session(session_id=session_id)
         expected = {'id':session_id,
                     'notebook':{'path': u'/path/to/test.ipynb'},
                     'kernel': {'id':u'A', 'name': 'bar'}}
@@ -140,7 +137,7 @@ class TestSessionManager(TestCase):
         session_id = self.create_session(path='/path/to/test.ipynb',
                                        kernel_name='julia')['id']
         sm.update_session(session_id, path='/path/to/new_name.ipynb')
-        model = self.loop.run_sync(lambda : sm.get_session(session_id=session_id))
+        model = sm.get_session(session_id=session_id)
         expected = {'id':session_id,
                     'notebook':{'path': u'/path/to/new_name.ipynb'},
                     'kernel':{'id':u'A', 'name':'julia'}}

notebook/tests/launchnotebook.py

@@ -19,6 +19,7 @@ except ImportError:
 
 from tornado.ioloop import IOLoop
 
+import jupyter_core.paths
 from ..notebookapp import NotebookApp
 from ipython_genutils.tempdir import TemporaryDirectory
 
@@ -51,9 +52,8 @@ class NotebookTestBase(TestCase):
             try:
                 requests.get(url)
             except Exception as e:
-                if cls.notebook.poll() is not None:
-                    raise RuntimeError("The notebook server exited with status %s" \
-                                        % cls.notebook.poll())
+                if not cls.notebook_thread.is_alive():
+                    raise RuntimeError("The notebook server failed to start")
                 time.sleep(POLL_INTERVAL)
             else:
                 return
@@ -77,31 +77,35 @@ class NotebookTestBase(TestCase):
             'JUPYTER_DATA_DIR' : data_dir.name
         })
         cls.env_patch.start()
+        cls.path_patch = patch.object(jupyter_core.paths, 'SYSTEM_JUPYTER_PATH', [])
+        cls.path_patch.start()
         cls.config_dir = TemporaryDirectory()
         cls.data_dir = data_dir
         cls.runtime_dir = TemporaryDirectory()
         cls.notebook_dir = TemporaryDirectory()
-        app = cls.notebook = NotebookApp(
-            port=cls.port,
-            port_retries=0,
-            open_browser=False,
-            config_dir=cls.config_dir.name,
-            data_dir=cls.data_dir.name,
-            runtime_dir=cls.runtime_dir.name,
-            notebook_dir=cls.notebook_dir.name,
-            base_url=cls.url_prefix,
-            config=cls.config,
-        )
         
-        # clear log handlers and propagate to root for nose to capture it
-        # needs to be redone after initialize, which reconfigures logging
-        app.log.propagate = True
-        app.log.handlers = []
-        app.initialize(argv=[])
-        app.log.propagate = True
-        app.log.handlers = []
         started = Event()
         def start_thread():
+            app = cls.notebook = NotebookApp(
+                port=cls.port,
+                port_retries=0,
+                open_browser=False,
+                config_dir=cls.config_dir.name,
+                data_dir=cls.data_dir.name,
+                runtime_dir=cls.runtime_dir.name,
+                notebook_dir=cls.notebook_dir.name,
+                base_url=cls.url_prefix,
+                config=cls.config,
+            )
+            # don't register signal handler during tests
+            app.init_signal = lambda : None
+            # clear log handlers and propagate to root for nose to capture it
+            # needs to be redone after initialize, which reconfigures logging
+            app.log.propagate = True
+            app.log.handlers = []
+            app.initialize(argv=[])
+            app.log.propagate = True
+            app.log.handlers = []
             loop = IOLoop.current()
             loop.add_callback(started.set)
             try:
@@ -109,6 +113,7 @@ class NotebookTestBase(TestCase):
             finally:
                 # set the event, so failure to start doesn't cause a hang
                 started.set()
+                app.session_manager.close()
         cls.notebook_thread = Thread(target=start_thread)
         cls.notebook_thread.start()
         started.wait()
@@ -118,12 +123,13 @@ class NotebookTestBase(TestCase):
     def teardown_class(cls):
         cls.notebook.stop()
         cls.wait_until_dead()
-        cls.env_patch.start()
         cls.home_dir.cleanup()
         cls.config_dir.cleanup()
         cls.data_dir.cleanup()
         cls.runtime_dir.cleanup()
         cls.notebook_dir.cleanup()
+        cls.env_patch.stop()
+        cls.path_patch.stop()
 
     @classmethod
     def base_url(cls):