SSL support / private keys

[ptitzler]

To support #2787, #2812, and #2797

• Elyra needs to provide access to certificate locations whenever an outbound HTTP request is made
• The user/administrator needs to configure the locations and make the certificates available

This could be accomplished as follows:

• augment all requests.XXX requests to optionally include the location of a certificate file or directory:
  • HOW
    • explicitly -> requests.get('https://domain.com', verify='/path/to/certfile')
    • implicitly -> set REQUESTS_CA_BUNDLE environment variable
  • WHERE
    • JupyterLab
    • generic component
• 'register' certificate file location
  • HOW
    • re-use REQUESTS_CA_BUNDLE environment variable (aka piggy-back on requests' solution)
    • re-use JupyterLab configuration setting (h/t @kevin-bates )
    • introduce custom environment variable
  • WHERE
    • JupyterLab (might require optional volume mount that exposes the certificates)
    • generic component (might require optional configmap, secret or volume mount that exposes the certificates)
    • custom components (might require optional configmap, secret or volume mount that exposes the certificates)

[ptitzler]

@kevin-bates re: 're-use JupyterLab configuration setting' (e.g c.ServerApp.certfile) this wouldn't be available to our backend code if one were to use the CLI to (for example) run a pipeline since no running JL instance is required, right?

[kevin-bates]

That is correct. I suppose we could look into loading that configuration to access the value of certfile or introduce a CLI option (since our CLI tools don't really leverage the Jupyter config framework (i.e., traitlets)) that is documented to be the same value as c.ServerApp.certfile.