ERROR:tornado.application:Future <tornado.concurrent.Future object at > exception was never ...

I hope some one can help me with the following error message:

ERROR:tornado.application:Future <tornado.concurrent.Future object at 0x7f4f4a4e9240> exception was never retrieved: tornado.iostream.StreamClosedError: Stream is closed

after running the code attached as:

python3 viewer_spectrum.py.

I am on Ubuntu 14.

To close the application hit the DONE button. Another tab will be opened and hit DONE again to close everything. It is when I press the DONE button a second time I get the above ERROR.

More context of my workflow:

I am building this viewer as part of an interactive viewer pipeline. I am trying to build the following capability:

Do for N times:

1. User does some processing with spectra.

2. User displays the spectra.

3. User hits DONE to get back to processing script (say a python script).

In the code attached N = 2.

Please note I am a beginner to Bokeh and browser based app development. I have put the attached code together based on previous question on this mailing list. Any help/feedback on the error and my code in general is appreciated.

Thanks

viewer_spectrum.py (3.26 KB)

Hi,

Despite being a beginner, I'd say this type of usage is quite novel and advanced. I think what you are seeing might be related to this:

  bokeh command leaves IOLoop.current set · Issue #3309 · bokeh/bokeh · GitHub

I think your use case is interesting and I'd like to help get to the bottom of it, but I am about to be away for two weeks, so I won't be able to investigate further until I am back.

That said I think the message is fairy harmless. Basically, AFAICT, it's just getting or trying to execute som coroutine after the session and ioloop are shut down. But, you are exiting the app anyway, so probably not a big deal.

Thanks,

Bryan