Type mismatch between Kubespawner and Helm Schema

[thomasv314]

Bug description

It is not immediately clear to me if this is an issue with the latest version of the jupyterhub chart, or Kubespawner.

There is a mismatch between the helm values for .singleuser.cpu.guarantee and the Kubespawner traitlets.

After upgrading to a version running off master, we see errors related to cpu limits/requests.

Expected behaviour

JupyterHub deploys / runs without issue.

Actual behaviour

Helm fails to deploy due to Schema validation issues:

Given the following values

  singleuser:
    cpu:
      limit: 2
      guarantee: 1

Deploying with helm errors out:

  Error: UPGRADE FAILED: values don't meet the specifications of the schema(s) in the following chart(s):
  jupyterhub:
  - singleuser.cpu.guarantee: Invalid type. Expected: [string,null], given: integer
  - singleuser.cpu.limit: Invalid type. Expected: [string,null], given: integer

When fixing the type in helm values, the deploy succeeds but the hub container errors out with:

   traitlets.traitlets.TraitError: The 'cpu_limit' trait of a KubeSpawner instance expected a float, not the str '2'.

How to reproduce

Try to sync with versions specified and the values provided above.

Your personal set up

Jupyterhub Chart: 10196f6 (0.11.1-n239.h10196f66)
Kubespawner: jupyterhub/kubespawner@a16e400

alembic==1.4.3
async-generator==1.10
attrs==20.3.0
bcrypt==3.2.0
boto3==1.17.14
botocore==1.20.14
cachetools==4.1.1
certifi==2020.12.5
certipy==0.1.3
cffi==1.14.4
chardet==3.0.4
conda==4.3.16
cryptography==3.4.4
entrypoints==0.3
escapism==1.0.1
google-auth==1.23.0
idna==2.10
ipython-genutils==0.2.0
Jinja2==2.11.2
jmespath==0.10.0
jsonschema==3.2.0
jupyter-telemetry==0.1.0
jupyterhub==1.3.0
jupyterhub-firstuseauthenticator==0.14.1
jupyterhub-hmacauthenticator==1.0
jupyterhub-idle-culler==1.0
jupyterhub-kubespawner @ git+https://github.com/jupyterhub/kubespawner.git@a16e400d69b2481863f3c6452273abbedb74f76a
jupyterhub-ldapauthenticator==1.3.2
jupyterhub-ltiauthenticator==1.0.0
jupyterhub-nativeauthenticator==0.0.7
jupyterhub-tmpauthenticator==0.6
kubernetes==12.0.1
ldap3==2.8.1
Mako==1.1.3
MarkupSafe==1.1.1
mwoauth==0.3.7
nullauthenticator==1.0.0
oauthenticator==0.13.0
oauthlib==3.1.0
onetimepass==1.0.1
pamela==1.0.0
prometheus-client==0.9.0
psycopg2-binary==2.8.6
py-spy==0.3.4
pyasn1==0.4.8
pyasn1-modules==0.2.8
pycosat==0.6.3
pycparser==2.20
pycurl==7.43.0.6
PyJWT==1.7.1
PyMySQL==1.0.2
pyOpenSSL==20.0.0
pyrsistent==0.17.3
python-dateutil==2.8.1
python-editor==1.0.4
python-json-logger==2.0.1
python-slugify==4.0.1
PyYAML==5.3.1
requests==2.25.0
requests-oauthlib==1.3.0
rsa==4.6
ruamel.yaml==0.16.12
ruamel.yaml.clib==0.2.2
s3transfer==0.3.4
six==1.15.0
SQLAlchemy==1.3.23
statsd==3.3.0
text-unidecode==1.3
tornado==6.1
traitlets==5.0.5
urllib3==1.26.2
websocket-client==0.57.0

• Configuration

# jupyterhub_config.py

• Logs

hub-7b65ffd55c-rjhmh:hub     Traceback (most recent call last):
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/jupyterhub/app.py", line 2856, in launch_instance_async
hub-7b65ffd55c-rjhmh:hub         await self.initialize(argv)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/jupyterhub/app.py", line 2428, in initialize
hub-7b65ffd55c-rjhmh:hub         await gen.with_timeout(
hub-7b65ffd55c-rjhmh:hub       File "/usr/lib/python3.8/asyncio/events.py", line 81, in _run
hub-7b65ffd55c-rjhmh:hub         self._context.run(self._callback, *self._args)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/jupyterhub/app.py", line 2413, in log_init_time
hub-7b65ffd55c-rjhmh:hub         n_spawners = f.result()
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/jupyterhub/app.py", line 2116, in init_spawners
hub-7b65ffd55c-rjhmh:hub         spawner = user.spawners[orm_spawner.name]
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/jupyterhub/user.py", line 186, in __getitem__
hub-7b65ffd55c-rjhmh:hub         self[key] = self.spawner_factory(key)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/jupyterhub/user.py", line 332, in _new_spawner
hub-7b65ffd55c-rjhmh:hub         spawner = spawner_class(**spawn_kwargs)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/kubespawner/spawner.py", line 162, in __init__
hub-7b65ffd55c-rjhmh:hub         super().__init__(*args, **kwargs)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/config/configurable.py", line 104, in __init__
hub-7b65ffd55c-rjhmh:hub         self.config = config
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 604, in __set__
hub-7b65ffd55c-rjhmh:hub         self.set(obj, value)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 593, in set
hub-7b65ffd55c-rjhmh:hub         obj._notify_trait(self.name, old_value, new_value)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 1217, in _notify_trait
hub-7b65ffd55c-rjhmh:hub         self.notify_change(Bunch(
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 1227, in notify_change
hub-7b65ffd55c-rjhmh:hub         return self._notify_observers(change)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 1264, in _notify_observers
hub-7b65ffd55c-rjhmh:hub         c(event)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 888, in compatible_observer
hub-7b65ffd55c-rjhmh:hub         return func(self, change)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/config/configurable.py", line 208, in _config_changed
hub-7b65ffd55c-rjhmh:hub         self._load_config(change.new, traits=traits, section_names=section_names)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/config/configurable.py", line 175, in _load_config
hub-7b65ffd55c-rjhmh:hub         setattr(self, name, deepcopy(config_value))
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 604, in __set__
hub-7b65ffd55c-rjhmh:hub         self.set(obj, value)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 578, in set
hub-7b65ffd55c-rjhmh:hub         new_value = self._validate(obj, value)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 610, in _validate
hub-7b65ffd55c-rjhmh:hub         value = self.validate(obj, value)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 2080, in validate
hub-7b65ffd55c-rjhmh:hub         self.error(obj, value)
hub-7b65ffd55c-rjhmh:hub       File "/usr/local/lib/python3.8/dist-packages/traitlets/traitlets.py", line 690, in error
hub-7b65ffd55c-rjhmh:hub         raise TraitError(e)
hub-7b65ffd55c-rjhmh:hub     traitlets.traitlets.TraitError: The 'cpu_limit' trait of a KubeSpawner instance expected a float, not the str '2'.

[consideRatio]

@thomasv314 ❤️ 🎉 thank you for reporting this, and doing it so clearly! This is an issue with z2jh following #2033.

[thomasv314]

@consideRatio no problem, much thanks for confirming it was a z2jjh issue.

The changes in #2069 resolved the issue

[consideRatio]

We ended up working in parallel! Thank you for reporting and contributing to fix this @thomasv314! ❤️ 🎉