The runner model is only a class responsible for storing information
now. Based on the configuration it picks a strategy for the runner
management. The Poseidon strategy is already implemented and tested.
The Docker strategy will follow.
This adds a button to the execution environment index page that, when
clicked, causes all execution environments to be synchronized to the
runner management (Poseidon) by creating or replacing them.
CodeOcean does not synchronize it's execution environments on startup or
when a new runner management configuration is used for the first time.
The administrator has to manually start this process by pressing this
button.
The equivalent for syncing just one execution environment is updating
it.
When creating or updating an execution environment, an API call to
Poseidon is made with the necessary information to create the
corresponding Nomad job.
If runner management is configured, his will display a warning
(currently in the same color as if it were a success) in the UI, if the
API call fails. The environment is saved even if it fails.
If runner management is not configured, this warning will not be created.
The old approach was to require the runner connection. This did
not work anymore with Zeitwerk in Rails 6. @sebastian.serth and I
moved the Connection class in `lib` into the ActiveRecord class
`Runner`. This will also work with future changes like specific
error classes. Furthermore the config was fixed and simplified.
Co-authored-by: Sebastian Serth <Sebastian.Serth@hpi.de>
