VS-Code starts blank in our JupyterHub setup (websocket failure)

[nthiery]

This is presumably an issue in our local setup rather than vscode-binder,
but here is hopefully a reasonable location to keep a record; also in case
this rings a bell.

Setup

Jupyterhub 0.8.1 running on a single server with DockerSpawner.
Image configuration from: https://gitlab.in2p3.fr/jupyterhub-paris-saclay/image/
(see the Dockerfile and environment.yml; docker image available from
Packages -> Container Registry).

Symptoms

The installation of vscode and the jupyter proxy presumably went smoothly.
VS Code appears as expected in the jupyter(lab) menu/launcher.
When running the docker container locally, VS Code works correctly.

However when launching VS Code in the same way from our JupyterHub, I get a blank screen.
In the JavaScript console, I get:

findTextAreas: running over 1 textareas.js:38:26
 INFO Error while creating indexedDB log provider. Falling back to in-memory log provider. log.ts:184:11
  ERR DOMException: "A mutation operation was attempted on a database that did not allow mutations." log.ts:196:11
Firefox ne peut établir de connexion avec le serveur à l’adresse wss://jupytercloud.lal.in2p3.fr/jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/?reconnectionToken=787a1474-2047-42e1-a477-144beb66bfce&reconnection=false&skipWebSocketFrames=false. browserSocketFactory.ts:162:30
  ERR [remote-connection][Management   ][787a1…][initial][jupytercloud.lal.in2p3.fr:80] socketFactory.connect() failed. Error: log.ts:196:11
  ERR Error: "WebSocket close with status code 1006"
    s remoteAuthorityResolver.ts:55
    l browserSocketFactory.ts:129
log.ts:196:11
  ERR [remote-connection] An error occurred in the very first connect attempt, it will be treated as a permanent error! Error: log.ts:196:11
  ERR Error: "WebSocket close with status code 1006"
    s remoteAuthorityResolver.ts:55
    l browserSocketFactory.ts:129
log.ts:196:11
  ERR Error: "WebSocket close with status code 1006"
    s remoteAuthorityResolver.ts:55
    l browserSocketFactory.ts:129
log.ts:196:11

In the Jupyter log, I get:

[I 2020-05-12 06:55:05.407 SingleUserNotebookApp log:174] 302 GET /jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/ -> /jupyter/hub/api/oauth2/authorize?client_id=user-nicolas.thiery-at-u-psud.fr&redirect_uri=%2Fjupyter%2Fuser%2Fnicolas.thiery-at-u-psud.fr%2Foauth_callback&response_type=code&state=[secret] (@127.0.0.1) 1.43ms
[E 2020-05-12 06:55:05.407 SingleUserNotebookApp web:1792] Uncaught exception GET /jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/ (127.0.0.1)
    HTTPServerRequest(protocol='http', host='jupytercloud.lal.in2p3.fr', method='GET', uri='/jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/', version='HTTP/1.1', remote_ip='127.0.0.1')
    Traceback (most recent call last):
      File "/opt/conda/lib/python3.7/site-packages/tornado/web.py", line 1703, in _execute
        result = await result
      File "/opt/conda/lib/python3.7/site-packages/jupyter_server_proxy/websocket.py", line 97, in get
        return await self.http_get(*args, **kwargs)
      File "/opt/conda/lib/python3.7/site-packages/jupyter_server_proxy/handlers.py", line 534, in http_get
        return await self.proxy(self.port, path)
    TypeError: object NoneType can't be used in 'await' expression
[I 2020-05-12 06:55:05.418 SingleUserNotebookApp log:174] 302 GET /jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/static-/out/vs/workbench/workbench.web.api.js -> /jupyter/hub/api/oauth2/authorize?client_id=user-nicolas.thiery-at-u-psud.fr&redirect_uri=%2Fjupyter%2Fuser%2Fnicolas.thiery-at-u-psud.fr%2Foauth_callback&response_type=code&state=[secret] (@127.0.0.1) 1.20ms
[E 2020-05-12 06:55:05.418 SingleUserNotebookApp web:1792] Uncaught exception GET /jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/static-/out/vs/workbench/workbench.web.api.js (127.0.0.1)
    HTTPServerRequest(protocol='http', host='jupytercloud.lal.in2p3.fr', method='GET', uri='/jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/static-/out/vs/workbench/workbench.web.api.js', version='HTTP/1.1', remote_ip='127.0.0.1')
    Traceback (most recent call last):
      File "/opt/conda/lib/python3.7/site-packages/tornado/web.py", line 1703, in _execute
        result = await result
      File "/opt/conda/lib/python3.7/site-packages/jupyter_server_proxy/websocket.py", line 97, in get
        return await self.http_get(*args, **kwargs)
      File "/opt/conda/lib/python3.7/site-packages/jupyter_server_proxy/handlers.py", line 534, in http_get
        return await self.proxy(self.port, path)
    TypeError: object NoneType can't be used in 'await' expression
[I 2020-05-12 06:55:05.420 SingleUserNotebookApp log:174] 302 GET /jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/static-/out/vs/workbench/workbench.web.api.nls.js -> /jupyter/hub/api/oauth2/authorize?client_id=user-nicolas.thiery-at-u-psud.fr&redirect_uri=%2Fjupyter%2Fuser%2Fnicolas.thiery-at-u-psud.fr%2Foauth_callback&response_type=code&state=[secret] (@127.0.0.1) 1.10ms
[E 2020-05-12 06:55:05.420 SingleUserNotebookApp web:1792] Uncaught exception GET /jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/static-/out/vs/workbench/workbench.web.api.nls.js (127.0.0.1)
    HTTPServerRequest(protocol='http', host='jupytercloud.lal.in2p3.fr', method='GET', uri='/jupyter/user/nicolas.thiery-at-u-psud.fr/vscode/static-/out/vs/workbench/workbench.web.api.nls.js', version='HTTP/1.1', remote_ip='127.0.0.1')
    Traceback (most recent call last):
      File "/opt/conda/lib/python3.7/site-packages/tornado/web.py", line 1703, in _execute
        result = await result
      File "/opt/conda/lib/python3.7/site-packages/jupyter_server_proxy/websocket.py", line 97, in get
        return await self.http_get(*args, **kwargs)
      File "/opt/conda/lib/python3.7/site-packages/jupyter_server_proxy/handlers.py", line 534, in http_get
        return await self.proxy(self.port, path)
    TypeError: object NoneType can't be used in 'await' expression

[betatim]

I think the networking part/firewall is fine. This is often a problem with websockets but seems to work here.

Seems more like someone changed/broke something in the jupyter-server-proxy we use or at least that is where this error is occuring. Do you know which version of it you are using? Probably worth reporting in their GitHub repo.

[betatim]

I just refreshed this repositories image on mybinder.org. This means it is using the latest and greatest jupyter-server-proxy available on conda-forge. This is v1.4.0 released ~3 days ago according to https://anaconda.org/conda-forge/jupyter-server-proxy

As far as I can tell it works on mybinder.org. Can you try if it also works for you and then see what happens locally if you upgrade/change to the same versions?

[nthiery]

jovyan@7eb3ed476be7:~$ conda list | grep proxy
configurable-http-proxy   4.2.1           node13_he01fd0c_0    conda-forge
jupyter-server-proxy      1.4.0                      py_0    conda-forge
jupyter-vscode-proxy      0.1                      pypi_0    pypi
jovyan@7eb3ed476be7:~$ pip list | grep proxy
jupyter-server-proxy              1.4.0
jupyter-vscode-proxy              0.1

[nthiery]

Thanks @betatim for the feedback!

The fact that things work if I use the docker image directly but don't in our JupyterHub may point more to a setup problem than a version problem. Although certain versions may have different use of the setup ...

[wzrzt]

In my case, vscode icon shows in jupyterlab launcher, but not jupyterhub's. Is there any instruction about making vscode show in jupyterhub launcher ?