RabbitMQ Task Queue Demo

A local demo of a distributed task queue built with RabbitMQ, Node.js, and React. Tasks are published via an Express/Socket.io producer, consumed by one or more workers, and results stream back to a live dashboard in real time. Failed tasks are routed to a dead-letter queue.

Architecture

Frontend (Vite/React)  →  Producer (Express + Socket.io)  →  RabbitMQ
                                        ↑                        ↓
                                   results queue            tasks queue
                                                                 ↓
                                                          Worker(s) (Node.js)

• Producer (producer/) — HTTP API on :3001, enqueues tasks, consumes the results queue, pushes updates to the frontend via WebSocket.
• Worker (worker/) — pulls tasks one at a time (prefetch(1)), simulates work (2–6 s), acks on success or nacks to the dead-letter queue on failure.
• Frontend (frontend/) — Vite/React dashboard, talks to the producer over HTTP and WebSocket.

Prerequisites

• Node.js v18+
• Docker (for RabbitMQ)

Local setup

1. Start RabbitMQ

docker compose up -d

RabbitMQ will be available at:

• AMQP: amqp://localhost:5672
• Management UI: http://localhost:15672 (guest / guest)

2. Install dependencies

Run this once in each package directory:

cd producer && npm install
cd ../worker  && npm install
cd ../frontend && npm install

3. Start the producer

cd producer
npm run dev

The API listens on http://localhost:3001.

4. Start one or more workers

Open a new terminal for each worker:

# terminal A
cd worker
WORKER_ID=alpha node src/worker.js

# terminal B
cd worker
WORKER_ID=beta node src/worker.js

WORKER_ID is optional — a random ID is generated if omitted.
FAIL_RATE (default 0.2) controls the simulated failure probability, e.g. FAIL_RATE=0.5.

5. Start the frontend

cd frontend
npm run dev

Open http://localhost:5173 in your browser.

Environment variables

Variable	Default	Description
RABBITMQ_URL	amqp://localhost	RabbitMQ connection URL (producer & worker)
PORT	3001	Producer HTTP port
WORKER_ID	random	Display name for the worker
FAIL_RATE	0.2	Fraction of tasks that deliberately fail (0–1)

Stopping

docker compose down