1. Open edX Platform Architecture#
The Open edX project is a web-based platform for creating, delivering, and analyzing online courses. It is the software that powers edx.org and many other online education sites.
This page explains the architecture of the platform at a high level, without getting into too many details.
There are a handful of major components in the Open edX project. Where possible, these communicate using stable, documented APIs.
The centerpiece of the Open edX architecture is edx-platform, which contains the learning management and course authoring applications (LMS and Studio, respectively).
This service is supported by a collection of other autonomous web services called independently deployed applications (IDAs). Over time, we plan to break out more of the existing edx-platform functions into new IDAs and MFEs (micro front-ends). This strategy will help manage the complexity of the edx-platform code base to make it as easy as possible for developers to approach and contribute to the project.
1.2. Key Components#
1.2.1. Learning Management System (LMS)#
The LMS is the experience that learners on Open edX sites see. It consists of various functionalities such as a dashboard of courses, views of various problem types, and progress pages for each course. Much of the LMS functionality, such as the in-course experience, Open Response Assessment (ORA) grading, and user profiles, is implemented via micro front-ends (MFEs).
LMS course content is written to a Mongo database.
Studio is the course authoring environment. Course teams use it to create and update courses. Studio writes its courses to the same Mongo database that the LMS uses.
Course discussions are implemented in the Discussions MFE. The discussions app allows learners and course staff interact with one another within a course run.
1.2.4. Mobile Apps#
The Open edX project includes a mobile application, available for iOS and Android, that allows learners to watch course videos and more. The Open edX community is actively enhancing the mobile apps.
The Data Working Group is currently building an analytics solution called Aspects.
1.2.6. Background Work#
A number of tasks are large enough that they are performed by separate background workers, rather than in the web applications themselves. This work is queued and distributed using Celery and Redis. Examples of queued work include:
Grading entire courses
Sending bulk emails (with Amazon SES)
Generating answer distribution reports
Producing end-of-course certificates
The Open edX project uses Elasticsearch for searching in multiple contexts, including course search and the comments service.
1.2.8. Other Components#
In addition to the components detailed above, the Open edX project also has services for other capabilities, such as one that manages e-commerce functions like order work flows and coupons.