django-user-tasks

django-user-tasks is a reusable Django application for managing user-triggered asynchronous tasks. It provides a status page for each such task, which includes a meaningful progress indicator if the task is currently being executed and provides any appropriate text and/or links for output once the task is complete.

In Open edX, such tasks include operations such as exporting or importing a course, sending an email to all the students in a course, uploading a video, and other tasks which often take too long to perform during a single web request (as outlined in OEP-3). However, this has been written with the intention of being useful in a variety of Django projects outside the Open edX platform as well.

Note that this library was created as a consolidation of lessons learned from implementing such tasks in various parts of the Open edX code base. They don't yet all use this library, but the plan is to over time refactor many of them to do so.

Overview

django-user-tasks is currently a wrapper for Celery (although the hope is that it could also be extended to also support channels and other asynchronous task queues). By extending the provided UserTask class (or adding UserTaskMixin to an existing Task subclass) and providing a user_id task argument, the task's status is stored in a database table separate from the Celery broker and result store. This UserTaskStatus model allows for full database queries of the tasks that users are most likely to care about while not imposing any restrictions on the Celery configuration most appropriate for the site's overall needs for asynchronous task processing.

Most of the status updating is handled automatically via Celery's signals mechanism, but it can be enhanced by:

• Overriding the UserTaskMixin methods such as generate_name and calculate_total_steps for particular types of tasks
• Calling some of the UserTaskStatus methods like increment_completed_steps and set_state from the task implementation
• Saving task output as instances of the UserTaskArtifact model

Documentation

The full documentation is at https://django-user-tasks.readthedocs.org.

License

The code in this repository is licensed under the Apache Software License 2.0 unless otherwise noted.

Please see LICENSE.txt for details.

How To Contribute

Contributions are very welcome.

Please read How To Contribute for details.

Reporting Security Issues

Please do not report security issues in public. Please email security@openedx.org.

Getting Help

Have a question about this repository, or about Open edX in general? Please refer to this list of resources if you need any assistance.