Cylc Hub configuration

[oliver-sanders]

At the moment we have the jupyterhub configuration defined in a single python file within the repo.

We intend to have all Cylc configuration files contained within the same tree for ease of management (cylc/cylc-flow#3170) something along the lines of this:

• <configuration_root_dir>/
  • flow/
    • 8.0.0/
      • flow.rc
    • 8.0.1/
      • flow.rc
  • hub/ (or ui-server?)
    • 1.0.0/
      • ui_server.py

How do we want to move forward with the configuration options:

• Do nothing:
  • Give users a template jupyterhub config file.
  • leave it up to them to put this file somewhere sensible.
  • Leave it up to them to specify the path to their own jupyterhub config file.
• Create a cylc hub command which:
  • Is a thin wrapper to jupyterhub which sets the config path:
    • Adds the jupytefhub_config.py file from this repo (which sets the logo etc).
    • Adds user/site config from the Cylc configuration tree.

Pull requests welcome!

[oliver-sanders]

Suggest creating a quick simple cylc hub command that wraps Jupyterhub:

• Easy to do with the cylc.command entry point.
• Should ensure jupyterhub runs with the Cylc configuration.
• Puts jupyterhub behind a cylc command (will appear to ps as such) which allows command whitelisting.
• Should also load the user config ~/.cylc/ui-server/[<version>/]jupyterhub_config.py (after the base Cylc config).
• This will bring the jupyterhub and uiserver configs into the same location, etc.
• Should still work when launched manually (providing you specify the base config file or are in the cylc-uiserver directory), you just loose the user config file stuff.
• Add a support for a site config later.

[oliver-sanders]

Added a cylc hub command in #173 along with a user config.

We now have the ability to define the configuration hierarchy how we want it, leaving this open as a question until we discuss & agree how we would like this to work.

[oliver-sanders]

superseded