RankMe

Application to manage users ranking based on Glicko rating system.

Architecture

System is designed using Command Query Responsibility Segregation (CQRS) and Event Sourcing patterns. Frontend is Single Page Application (SPA) implemented in Angular Framework. Backend application contains multiple microservices that are standard Spring Boot applications.

Backend services might be divided into two types:

Infrastructure services

• config-service - service that contains and propagate configuration for other services.
• discovery-service - services registry.
• gateway-service - service for handling and distributing HTTP traffic.

Functional services

• api-service - service that contains GraphQL API and orchestrate CQRS commands and queries.
• command-service - service for handling CQRS commands.
• query-service - service for handling CQRS queries.
• subscription-service - service emit CQRS read-model changes events

Diagram

Application start

Requirements:

• Gradle 7
• Java 11
• Angular CLI 12
• Docker, Docker Compose

To start the whole system it needs to run both backend and frontend parts.

Backend

• Go to project root directory
• Build application using Gradle gradle clean build
• Run docker-compose up

Services:

• http://localhost:9010 - Config service
• http://localhost:9020 - Gateway service
• http://localhost:9030 - Eureka Discovery Service
• http://localhost:9040/graphiql - GraphQL API
• http://localhost:9050 - Command service
• http://localhost:9060 - Query service
• http://localhost:9070 - Subscription service

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All services might be also run separately without Docker as standard Spring Boot Application. They require running RabbitMQ, MongoDB and PostgreSQL/Event Store instances.

Frontend

• Go to webapp directory
• Install NPM dependencies using npm install
• Run ng serve

Application is available under http://localhost:4200