Profile plugin in blank when redirected with juypter_server_proxy

[rsarm]

Hi. I use tensorboard within a jupyter notebook that runs remotely and it's accessible through juypterhub. Since on the remote host, tensorboard will be running on localhost:6006, I use juypter_server_proxy to redirect it through the notebook's server. I do that through monkey-patching tensorboard.notebook._display_ipython as follows

import tensorboard
from IPython import get_ipython


def _display_ipython(port, height, display_handle):
    import os
    import IPython.display
    iframe = IPython.display.IFrame(
        src="https://<jupyter-url>/hub/user-redirect/proxy/%d/#scalars" % (os.environ['USER'], port),
        height=height,
        width="100%",
    )
    if display_handle:
        display_handle.update(iframe)
    else:
        IPython.display.display(iframe)


ipy = get_ipython()
tensorboard.notebook._load_ipython_extension(ipy)

tensorboard.notebook._display_ipython = _display_ipython

That works fine. The scalars, histograms, etc, show up fine, but the profile tab shows a blank page. Both within the notebook or directly on the browser. Using ssh tunnels from the host to my laptop, I checked that the profiler shows up fine. The problem seems to be with the redirecting.

I see that the blank page has an iframe <iframe id="dashboard" src="http://<jupyter-url>/hub/user-redirect/proxy/6006/data/plugin_entry.html?name=profile"></iframe>. I tried pasting that url directly to the browser, and it does some redirects which ends up in a blank page http://<jupyter-url>/hub/user-redirect/proxy/6006/data/profile/index.html. Doing the same, with a tensorboard running un my laptop, these last redirects end up on a working profiler with a longer url http://localhost:6006/data/plugin/profile/overview_page@;ea=20200615-211507%2Ftrain%2F2020_06_15_21_15_10;tag=overview_page@;host=nid06882. I think with the way I'm doing the proxying through jupyter, I'm messing up with tensorboard's redirects.

Do you have some workaround for the case of JuypterHub? Otherwise could you please, point me to where I could add a fix for my use case.

[psybuzz]

Thank you for the report. I haven't gotten around to investigation of this yet. Could you please share your version #s for tensorboard and jupyter hub?

[rsarm]

Thanks a lot for looking into this! We have tensorboard-2.2.1 and juypterhub-1.0.0.

[rsarm]

I just tested again with tensorboard-plugin-profile-2.3.0/tensorboard-2.3.0 and the profiler shows up fine. Thanks!

[psybuzz]

Thanks for verifying that it works in 2.3.0. I wasn't able to deeply investigate the problem, but since it's solved with a version bump, I suspect it might be due to the fix that landed in 2.3 - #3674.

Closing this issue.