`nextstrain view` automatic opening of browser does not work on Windows

[victorlin]

This was brought up by a user at office hours. Here is the relevant output after running nextstrain view (computer-specific details cropped out):

There is an error in the middle:

Traceback (most recent call last):
  File "multiprocessing.spawn", line 107, in spawn_main
  File "multiprocessing.reduction", line 79, in duplicate
TypeError: DuplicateHandle() argument 2 must be int, not dict

There is an upstream issue, but it's likely that it won't be fixed any time soon since PyOxidizer is unmaintained.

Separately, we may want to consider not letting nextstrain view continue to run after this sort of error.

Note: no office hours hosts have tried to reproduce this yet, since we don't actively use Windows machines.

[tsibley]

Bah. We can probably work around this one way or another.

For doing Windows-focused development/testing of Nextstrain CLI in the past, I've used both a Windows VM and the ThinkPad with Windows on it in lab.

[tsibley]

since we don't actively use Windows machines.

This fact will mean that Windows support will always be a bit hit-or-miss and shoddy, unfortunately. :/

[tsibley]

I believe only the automatic opening of a web browser is broken here, based on the code and screenshot above. Note that Auspice appears to be running in the screenshot, and this is supported by the logic flow in the code. The TypeError in the screenshot appears to be coming from the browser-opening process, i.e. its already a separate process and multiprocessing is setting things up (and failing).

If the user hit http://127.0.0.1:4000/zika even after seeing this error, I believe they'd see the expected dataset. And I believe passing --no-open would suppress the error.

[joverlee521]

Ah, the TypeError is probably a red herring then. The user could not see their dataset at https://127.0.0.1:4000/zika so we were trying to figure out why...

[tsibley]

This is the Docker runtime, it looks like. So probably a port forwarding issue then?

[tsibley]

I can repro the TypeError from multiprocessing, but I can't repo http://127.0.0.1:4000/zika (note http not https) being inaccessible.

[joverlee521]

Looks like they resolved the port forwarding issue by uninstalling and reinstalling, but the automatic opening of the web browser is still broken.