This is a very large refactoring which aims at making Tutor both more
extendable and more generic. Historically, the Tutor plugin system was
designed as an ad-hoc solution to allow developers to modify their own
Open edX platforms without having to fork Tutor. The plugin API was
simple, but limited, because of its ad-hoc nature. As a consequence,
there were many things that plugin developers could not do, such as
extending different parts of the CLI or adding custom template filters.
Here, we refactor the whole codebase to make use of a generic plugin
system. This system was inspired by the Wordpress plugin API and the
Open edX "hooks and filters" API. The various components are added to a
small core thanks to a set of actions and filters. Actions are callback
functions that can be triggered at different points of the application
lifecycle. Filters are functions that modify some data. Both actions and
filters are collectively named as "hooks". Hooks can optionally be
created within a certain context, which makes it easier to keep track of
which application created which callback.
This new hooks system allows us to provide a Python API that developers
can use to extend their applications. The API reference is added to the
documentation, along with a new plugin development tutorial.
The plugin v0 API remains supported for backward compatibility of
existing plugins.
Done:
- Do not load commands from plugins which are not enabled.
- Load enabled plugins once on start.
- Implement contexts for actions and filters, which allow us to keep track of
the source of every hook.
- Migrate patches
- Migrate commands
- Migrate plugin detection
- Migrate templates_root
- Migrate config
- Migrate template environment globals and filters
- Migrate hooks to tasks
- Generate hook documentation
- Generate patch reference documentation
- Add the concept of action priority
Close #499.
I stumbled upon a bug that should have been detected by the type
checking. Turns out, considering that config is of type Dict[str, Any]
means that we can use just any method on all config values -- which is
terrible. I discovered this after I set `config["PLUGINS"] = None`:
this triggered a crash when I enabled a plugin.
We resolve this by making the Config type more explicit. We also take
the opportunity to remove a few cast statements.
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We are running in strict mode, which is awesome!
This affects a large part of the code base, which might be an issue for
people running a fork of Tutor. Nonetheless, the behavior should not be
affected. If anything, this process has helped find and resolve a few
type-related bugs. Thus, this is not considered as a breaking change.
Previously, it was not possible to override the docker registry for just
one or a few services. Setting the DOCKER_REGISTRY configuration
parameter would apply to all images. This was inconvenient. To resolve
this, we include the docker registry value in the DOCKER_IMAGE_*
configuration parameters. This allows users to override the docker
registry individually by defining the DOCKER_IMAGE_SERVICENAME
configuration parameter.
See https://discuss.overhang.io/t/kubernetes-ci-cd-pipeline/765/3
The `dev` commands now rely on a different openedx-dev docker image.
This gives us multiple improvements:
- no more chown in base image
- faster chown in development
- mounted requirements volume in development
- fix static assets issues
- bundled ipdb/vim/... packages, which are convenient for development
Close #235
Environment is no longer generated separately for each target, but only
once the configuration is saved.
Note that the environment is automatically updated during
re-configuration, based on a "version" file stored in the environment.
Replace all make commands by a single "tutor" binary. Environment and
data are all moved to ~/.tutor/local/share/tutor. We take the
opportunity to add a web UI and revamp the documentation.
This is a complete rewrite.
Close #121.
Close #147.