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.
We were forced to pin click to < v8 because of missing dependencies. In
particular, click_repl was broken. This is no longer the case, as click_repl
0.20 was published. Also, Jinja2 now includes type annotations, which allows us
to get rid of a few "# type: ignore" statements.
We take the opportunity to upgrade all requirements, which allows us resolve a
security issue on urllib3<1.26.0.
All pallets project requirement had a major upgrade today:
https://palletsprojects.com/blog/flask-2-0-released/
We are not yet compatible with click 8.0 and others. In particular,
click-repl imports modules which are no longer available. Until we can
upgrade, we add constraints to the requirements files.
The following error was being raised:
$ tutor plugins list
Traceback (most recent call last):
File "/home/data/regis/tmp/testtutor/bin/tutor", line 5, in <module>
from tutor.commands.cli import main
File "/home/data/regis/tmp/testtutor/lib/python3.6/site-packages/tutor/commands/cli.py", line 6, in <module>
import click_repl
File "/home/data/regis/tmp/testtutor/lib/python3.6/site-packages/click_repl/__init__.py", line 6, in <module>
import click._bashcomplete
ModuleNotFoundError: No module named 'click._bashcomplete'
Close #430.
Annotations were generated with pyannotate:
https://github.com/dropbox/pyannotate
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.
requests depends on urllib3<1.26.0, while urllib3==1.26.0 was just
released. We need to introduce a constraint on urllib3 to avoid the
following error when running `pip install -e`:
pkg_resources.ContextualVersionConflict: (urllib3 1.26.0
(./venv/lib/python3.7/site-packages),
Requirement.parse('urllib3!=1.25.0,!=1.25.1,<1.26,>=1.21.1'),
{'requests'})
We will be able to remove this constraint once requests becomes
compatible with urllib3==1.26.0. To test this change just run `pip
install -e tutor` and then run a dummy command, such as `tutor local
stop`.
Here, we upgrade the Open edX platform from Ironwood to Juniper. This
upgrade does not come with many feature changes, but there are many
technical improvements under the hood:
- Upgrade from Python 2.7 to 3.5
- Upgrade from Mongodb v3.2 to v3.6
- Upgrade Ruby to 2.5.7
We took the opportunity to completely rething the way locally running
platforms should be accessed for testing purposes. It is no longer
possible to access a running platform from http://localhost and
http://studio.localhost. Instead, users should access
http://local.overhang.io and https://studio.local.overhang.io. This
drastically simplifies internal communication between Docker containers.
To upgrade, users should simply run:
tutor local quickstart
For Kubernetes platform, the upgrade process is outlined when running:
tutor k8s upgrade --from=ironwood
Running jobs was previously done with "exec". This was because it
allowed us to avoid copying too much container specification information
from the docker-compose/deployments files to the jobs files. However,
this was limiting:
- In order to run a job, the corresponding container had to be running.
This was particularly painful in Kubernetes, where containers are
crashing as long as migrations are not correctly run.
- Containers in which we need to run jobs needed to be present in the
docker-compose/deployments files. This is unnecessary, for example when
mysql is disabled, or in the case of the certbot container.
Now, we create dedicated jobs files, both for local and k8s deployment.
This introduces a little redundancy, but not too much. Note that
dependent containers are not listed in the docker-compose.jobs.yml file,
so an actual platform is still supposed to be running when we launch the
jobs.
This also introduces a subtle change: now, jobs go through the container
entrypoint prior to running. This is probably a good thing, as it will
avoid forgetting about incorrect environment variables.
In k8s, we find ourselves interacting way too much with the kubectl
utility. Parsing output from the CLI is a pain. So we need to switch to
the native kubernetes client library.
We were getting the following warning with the latest version of pyyaml:
YAMLLoadWarning: calling yaml.load() without Loader=... is
deprecated, as the default Loader is unsafe. Please read
https://msg.pyyaml.org/load for full details.
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.
