TeleQueue

⚡ Status: Currently under active development.

TeleQueue is a high-performance distributed queue and appointment scheduling system being built with NestJS, Kafka, PostgreSQL, Elasticsearch, and Rust. It is being designed to handle large-scale, real-time processing with strict ordering and fault tolerance. For real life scenario where booking request spikes the moment booking is opened.

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Features

• Distributed Sequencer: Powered by Rust (Raft-based) to guarantee globally unique, strictly ordered sequence IDs.
• Event-driven Architecture: Kafka as the backbone for reliable message streaming.
• Microservices: Modular services like api-gateway, appointments, and queues.
• Elasticsearch Integration: Real-time indexing and advanced search queries.
• PostgreSQL Database: Primary relational storage for transactional data.
• Dockerized Environment: Ready-to-run with docker-compose.
• Scalable Design: Horizontal scaling via Kafka partitions and microservices.

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Tech Stack

• Backend: NestJS, TypeScript
• Messaging: Kafka
• Database: PostgreSQL
• Search Engine: Elasticsearch
• Rust: Raft-based distributed sequencer
• Containerization: Docker & Docker Compose

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Architecture

[ API Gateway ] <---> [ Appointments Service ]
      |                      |
      |                      v
      |                  [ Queues Service ] <---> [ Kafka ]
      |                                              |
      |                                              v
      |                                     [ PostgreSQL / Elasticsearch ]
      |
      v
[ Clients (REST) ]

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Getting Started

1. Clone the Repository

git clone https://github.com/tsabudh/telequeue.git
cd telequeue

2. Environment Variables

Create .env files in each service (e.g., apps/api-gateway/.env) with appropriate values: Create .env apps/appointment/.env:

HTTP_PORT=3001

Create .env apps/appointment/.env:

KAFKA_BROKER=kafka:9092
ELASTICSEARCH_URL=http://elasticsearch:9200

Create .env libs/common/src/.env:

DATABASE_URL=postgresql://telequeue_app:telequeue_pass@postgres:5432/telequeue_write_db
KAFKA_BROKER=kafka:9092

3. Start the Services

Use Docker Compose:

docker-compose up --build

The API gateway will be available on:

• API Gateway: http://localhost:3001

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Available Services

• api-gateway: Entry point for clients (REST/GraphQL).
• appointments: Manages appointment scheduling.
• queues: Handles queue management and distributed sequencing. (in development)
• postgres: Database for transactional data. (in development)
• kafka: Message streaming backbone.
• elasticsearch: Full-text search and analytics. (in development)

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Development

Watch Mode

Run any service in watch mode:

Syntax

npm run start:dev -- apps/{service-name}

Example

npm run start:dev -- apps/api-gateway

Migrations

To run database migrations (if using TypeORM):

npm run typeorm migration:run

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Testing

npm run test
npm run test:e2e
npm run lint

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Contributing

We welcome contributions! Please:

1. Fork the repo.
2. Create a feature branch.
3. Submit a pull request.

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License

This project is licensed under the MIT License.

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Future Roadmap

• Integrate gRPC communication between microservices.
• Implement Raft-based leader election for the Rust sequencer with horizontal scaling.
• Add monitoring and observability (Prometheus + Grafana).

• Improve horizontal scalability with Kafka partition optimization.

• Enhance API Gateway with GraphQL Federation and caching.
• Add authentication & authorization (OAuth2 / JWT).
• Automate Kafka topic management and monitoring.
• Set up CI/CD pipeline (GitHub Actions / GitLab CI).