[notebook] Can't close a notebook without errors

[michaelaye]

I start a notebook server with 'ipython notebook --pylab'.

When I am closing a notebook via File->Close and Halt, I am getting
almost always the following errors in my terminal:

[NotebookApp] Kernel started: 673e9899-6ec5-41b0-958e-f6c9cd573794
[NotebookApp] Connecting to: tcp://127.0.0.1:57981
[NotebookApp] Connecting to: tcp://127.0.0.1:57982
[NotebookApp] Connecting to: tcp://127.0.0.1:57984
[IPKernelApp] To connect another client to this kernel, use:
[IPKernelApp] --existing kernel-673e9899-6ec5-41b0-958e-f6c9cd573794.json

[NotebookApp] Kernel shutdown: 673e9899-6ec5-41b0-958e-f6c9cd573794
WARNING:root:Read error on 6: [Errno 54] Connection reset by peer
ERROR:root:Uncaught exception DELETE 
/kernels/673e9899-6ec5-41b0-958e-f6c9cd573794 (127.0.0.1)
HTTPRequest(protocol='http', host='127.0.0.1:8888', method='DELETE', 
uri='/kernels/673e9899-6ec5-41b0-958e-f6c9cd573794', 
version='HTTP/1.1', remote_ip='127.0.0.1', body='', headers={'Origin': 
'http://127.0.0.1:8888', 'Content-Length': '0', 'Accept-Language': 
'en-us', 'Accept-Encoding': 'gzip, deflate', 'Host': '127.0.0.1:8888', 
'Accept': '*/*', 'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 
10_8_3) AppleWebKit/536.28.10 (KHTML, like Gecko) Version/6.0.3 
Safari/536.28.10', 'Connection': 'keep-alive', 'X-Requested-With': 
'XMLHttpRequest', 'Referer': 
'http://127.0.0.1:8888/2761cf04-c906-4762-b69d-feba4ebf32f6'})
Traceback (most recent call last):
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 988, in _execute
    getattr(self, self.request.method.lower())(*args, **kwargs)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 1739, in wrapper
    return method(self, *args, **kwargs)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/IPython/frontend/html/notebook/handlers.py", 
line 351, in delete
    self.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 669, in finish
    self.request.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 422, in finish
    self.connection.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 186, in finish
    self._finish_request()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 222, in _finish_request
    self.stream.read_until(b("\r\n\r\n"), self._header_callback)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/iostream.py", 
line 161, in read_until
    if self._read_to_buffer() == 0:
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/iostream.py", 
line 378, in _read_to_buffer
    chunk = self._read_from_socket()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/iostream.py", 
line 359, in _read_from_socket
    chunk = self.socket.recv(self.read_chunk_size)
error: [Errno 54] Connection reset by peer
ERROR:root:Cannot send error response after headers written
ERROR:root:Uncaught exception, closing connection.
Traceback (most recent call last):
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/iostream.py", 
line 304, in wrapper
    callback(*args)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 280, in _on_request_body
    self.request_callback(self._request)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 1362, in __call__
    handler._execute(transforms, *args, **kwargs)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 992, in _execute
    self._handle_request_exception(e)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 1032, in _handle_request_exception
    self.send_error(500, exc_info=sys.exc_info())
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 688, in send_error
    self.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 669, in finish
    self.request.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 422, in finish
    self.connection.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 183, in finish
    assert self._request, "Request closed"
AssertionError: Request closed
ERROR:root:Exception in callback 
<zmq.eventloop.stack_context._StackContextWrapper object at 0x108d45578>
Traceback (most recent call last):
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/zmq/eventloop/ioloop.py", 
line 440, in _run_callback
    callback()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/iostream.py", 
line 304, in wrapper
    callback(*args)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 280, in _on_request_body
    self.request_callback(self._request)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 1362, in __call__
    handler._execute(transforms, *args, **kwargs)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 992, in _execute
    self._handle_request_exception(e)
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 1032, in _handle_request_exception
    self.send_error(500, exc_info=sys.exc_info())
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 688, in send_error
    self.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/web.py", 
line 669, in finish
    self.request.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 422, in finish
    self.connection.finish()
  File 
"/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/tornado/httpserver.py", 
line 183, in finish
    assert self._request, "Request closed"
AssertionError: Request closed
WARNING:root:Read error on 35: [Errno 54] Connection reset by peer

I found this related question on SO:

http://stackoverflow.com/questions/6697322/tornado-ioerror-stream-is-closed-on-request-finish

The notebook is being closed alright and I get back to the dashboard.

Is there any way to stop this annoyance?

Michael

PS.: Am using IPython 0.13.2 from github, installed into an EPD 7.3-2,
calling it inside a iTerm2 terminal on Mac OSX 10.8.3.

[minrk]

We should wrap self.finish in a try/except on delete, so this doesn't happen.

[minrk]

what tornado version?

[michaelaye]

In [3]: tornado.version
Out[3]: '2.2'

[michaelaye]

I report that this issue is solved with tornado 3.1 and IPython master: 719de27