Architecture
This document uses the C4 Model for visualising the architecture of grand-challenge.org. This covers System Context, Containers (Applications/Data Stores), and Components (Modules/Libraries).
Ubiquitous Language
Users
Many different users and roles are supported on grand-challenge.org.
- Researcher
A Researcher is a user who wants to manage medical imaging data and reports, collect annotations on medical imaging data, create a challenge for the data science community to generate solutions to clinical problems, and objectively evaluate the submitted algorithms to challenges.
- Data Scientist
A Data Scientist is a user who participates in a challenge, downloads the training medical imaging data & annotations for a challenge, uploads algorithms for a challenge, and makes those algorithms available for clinicians to execute.
- Clinician
A Clinician is a user who uses a workstation to learn how to annotate or read medical imaging data, uses a workstation to make annotations to medical imaging data, and uploads new medical imaging data for execution by algorithms.
System Context
An overview of the grand-challenge.org system, its users, and its system dependencies.
Containers
The overall shape of the architecture and technology choices. Note: a container is a separately deployable application or data store, not necessarily a Docker container.
Components
Logical modules and their interactions with containers. Note: a component is a grouping of related functionality behind a well defined interface, not components in the sense of pipelines. Grand-challenge.org is a Django monolith, but several components can be deployed and scaled independently.
API
The API layer provides the HTML views and REST services to the user.
Workstations
Grand Challenge is able to launch workstations for users. Workstations are container images that allow for interaction with medical data in the browser. One workstation container image is instantiated per user, which provides a single page application. A secure web socket connection is then established between the user and their container instance.
Image, Evaluation and Algorithm Workers
There are several tasks that require asynchronous processing that require long compute times, high memory usage and potentially the docker api and/or a GPU. These tasks include medical image importing, challenge submission evaluation (requires docker), and algorithm execution (requires docker and a GPU). These tasks are scheduled using Celery, and then executed by worker nodes that can horizontally scale.
