Intro

JAlgoArena conducts many parts, which can be divided to:

• Node.JS hosted Web UI
• Traefik as Edge Service
• Nomad as scheduler
• Consul for Service Discovery
• Apache Kafka used for messaging internally in the backend
• Elastic Stack for capturing distributed logs
• Cockroach DB for highly available data storage
• JAlgoArena microservices delivering core features

Diagram

1. Publish submission to Kafka.
2. Save new submission (JAlgoArena-Submissions) & start judge process (JAlgoArena-Judge)
   1. Request submissions refresh via WebSocket subscriptions (JAlgoArena-Submissions)
3. Publish submission result
4. Store submission and ranking result (the second only if submission is accepted)
5. Request ranking & submissions refresh via WebSocket subscriptions

Components

JAlgoArena microservices:

• JAlgoArena UI - host UI components, runs reverse proxy using Service Discovery for resolving edge service
• JAlgoArena Auth - microservice responsible for authentication and storing users data
• JAlgoArena Queue - microservice serving queue for incoming submissions, publishing them to Apache Kafka
• JAlgoArena Submissions - microservice storing all submissions and serving data based on collected data
• JAlgoArena Judge - main microservice responsible for judging incoming submissions
• JAlgoArena Ranking - microservice focused on building ranking from successful submissions (ranking storage)
• JAlgoArena Events - microservice responsible for publishing events about submissions or ranking refreshes