Node.js Microservices — Task App

Node.js microservices example implementing a simple Task App using MongoDB, RabbitMQ and Docker.

Overview

This repository contains a small set of microservices that together implement a Task management application.

• Auth service manages credentials and issues JWTs.
• User service manages user profile data.
• Task service manages tasks and publishes task events to RabbitMQ.
• Notification service consumes RabbitMQ events.

Services are containerized with Docker Compose, and can also be run locally.

Tech Stack

• Platform: Node.js microservices
• Frameworks/Libraries: Express, Mongoose
• Database: MongoDB
• Broker: RabbitMQ
• Containers: Docker & Docker Compose

Features

• User registration/login using JWT
• User profile CRUD (separate from auth data)
• Task creation and list
• Task events published to RabbitMQ (consumed by notification-service)

Repository layout

• auth-service/ — authentication API (JWT + users collection)
• user-service/ — user profile API
• task-service/ — task CRUD + RabbitMQ publisher
• notification-service/ — RabbitMQ consumer (notifications)
• docker-compose.yml — orchestration for all services, MongoDB and RabbitMQ
• readme/design-auth.svg — architecture diagram

Architecture

Exporting the diagram to PNG

• VS Code:
  • Install an extension that supports Mermaid rendering/export (for example, "Markdown Preview Mermaid Support" or a Mermaid exporter).
  • Export the Mermaid block as an image.
• GitHub:
  • GitHub renders Mermaid in Markdown; you can take a screenshot or use a Mermaid export tool.

If you want, tell me whether you prefer PNG or SVG, and I’ll generate a text-based diagram file (SVG) under readme/ that you can commit and render anywhere.

Service Ports

• Auth Service: 3004
• User Service: 3001
• Task Service: 3002
• Notification Service: 3003
• RabbitMQ Management UI: 15672
• MongoDB: 27017

Getting started (Docker Compose)

1. Ensure Docker and Docker Compose are installed.
2. From the repository root, bring up all services:

docker-compose up -d --build

3. Watch logs for a service (example):

docker-compose logs -f auth-service

Run locally (development)

You can still use MongoDB/RabbitMQ from Docker and run a service on your machine.

Example:

cd auth-service
npm install
npm run dev

Environment

At repo root there is a shared .env file used by Docker Compose.

Root .env (used by docker-compose)

NODE_ENV=development
JWT_SECRET=your_secure_jwt_secret_key_here
JWT_EXPIRES_IN=1d

AUTH_SERVICE_PORT=3004
USER_SERVICE_PORT=3001
TASK_SERVICE_PORT=3002
NOTIFICATION_SERVICE_PORT=3003

MONGODB_URI=mongodb://mongo:27017/
RABBITMQ_URL=amqp://rabbitmq

AUTH_SERVICE_URL=http://localhost:3004
USER_SERVICE_URL=http://localhost:3001
TASK_SERVICE_URL=http://localhost:3002
NOTIFICATION_SERVICE_URL=http://localhost:3003

Important: Container URLs vs Localhost URLs

• Inside Docker Compose, services should call each other via service names:
  • Example: http://user-service:3001
• From your browser / Postman / curl on your machine, use http://localhost:<port>.

In docker-compose.yml:

• auth-service uses USER_SERVICE_URL=http://user-service:3001 (container-to-container).
• Some services may also have AUTH_SERVICE_URL=http://localhost:3004 (this only works if the container can reach your host network, and is not recommended for container-to-container calls).

Data Model (Important)

This project intentionally separates authentication data and profile data:

• Auth DB (auth) → users collection
  • Stores: email, username, password (hashed), role
• Users DB (users) → userprofiles collection
  • Stores: userId (links to auth user _id), name, email, profile fields (bio, avatar, preferences)

The link is the userId stored in userprofiles.

API Documentation

Base URLs (local):

• Auth: http://localhost:3004
• Users: http://localhost:3001
• Tasks: http://localhost:3002

Auth Service (auth-service)

Register

POST /api/auth/register

Creates a new auth user and then creates a matching user profile in user-service.

Request body:

{
  "name": "John Doe",
  "email": "john.doe@example.com",
  "username": "johndoe",
  "password": "SecurePassword123!"
}

Response 201:

{
  "user": {
    "_id": "<mongo_object_id>",
    "email": "john.doe@example.com",
    "username": "johndoe",
    "role": "user",
    "createdAt": "2025-12-30T00:00:00.000Z",
    "updatedAt": "2025-12-30T00:00:00.000Z"
  },
  "token": "<jwt>"
}

Notes:

• First registered user becomes admin (see auth-service logic).
• Password is never returned.

curl:

curl -X POST "http://localhost:3004/api/auth/register" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "John Doe",
    "email": "john.doe@example.com",
    "username": "johndoe",
    "password": "SecurePassword123!"
  }'

Login

POST /api/auth/login

Request body:

{
  "username": "johndoe",
  "password": "SecurePassword123!"
}

Notes:

• username field accepts username or email.

Response 200:

{
  "user": {
    "_id": "<mongo_object_id>",
    "email": "john.doe@example.com",
    "username": "johndoe",
    "role": "user",
    "id": "<profile_id>",
    "userId": "<mongo_object_id>",
    "name": "John Doe",
    "bio": "",
    "avatar": "",
    "preferences": {
      "theme": "light",
      "notifications": {
        "email": true,
        "push": true
      }
    },
    "createdAt": "2025-12-30T00:00:00.000Z",
    "updatedAt": "2025-12-30T00:00:00.000Z"
  },
  "token": "<jwt>"
}

curl:

curl -X POST "http://localhost:3004/api/auth/login" \
  -H "Content-Type: application/json" \
  -d '{
    "username": "johndoe",
    "password": "SecurePassword123!"
  }'

Get current user

GET /api/auth/me

Headers:

Authorization: Bearer <jwt>

Response 200 combines auth user + user profile:

{
  "_id": "<mongo_object_id>",
  "email": "john.doe@example.com",
  "username": "johndoe",
  "role": "user",
  "id": "<profile_id>",
  "userId": "<mongo_object_id>",
  "name": "John Doe",
  "bio": "",
  "avatar": "",
  "preferences": {
    "theme": "light",
    "notifications": {
      "email": true,
      "push": true
    }
  },
  "createdAt": "2025-12-30T00:00:00.000Z",
  "updatedAt": "2025-12-30T00:00:00.000Z"
}

curl:

curl "http://localhost:3004/api/auth/me" \
  -H "Authorization: Bearer <jwt>"

Logout

There is no server-side logout endpoint.

This project uses stateless JWT, so logout is handled by the client by deleting the token.

User Service (user-service)

All user-service endpoints require:

Authorization: Bearer <jwt>

Get my profile

GET /api/users/me

Response 200:

{
  "id": "<profile_id>",
  "userId": "<auth_user_id>",
  "name": "John Doe",
  "email": "john.doe@example.com",
  "bio": "",
  "avatar": "",
  "preferences": {
    "theme": "light",
    "notifications": {
      "email": true,
      "push": true
    }
  },
  "createdAt": "2025-12-30T00:00:00.000Z",
  "updatedAt": "2025-12-30T00:00:00.000Z"
}

curl:

curl "http://localhost:3001/api/users/me" \
  -H "Authorization: Bearer <jwt>"

Update my profile

PATCH /api/users/me

Request body (example):

{
  "bio": "Senior developer",
  "preferences": {
    "theme": "dark"
  }
}

curl:

curl -X PATCH "http://localhost:3001/api/users/me" \
  -H "Authorization: Bearer <jwt>" \
  -H "Content-Type: application/json" \
  -d '{
    "bio": "Senior developer",
    "preferences": {"theme": "dark"}
  }'

List all users (Admin only)

GET /api/users?page=1&limit=10

Requirements:

• JWT must include role: "admin".

Response 200:

{
  "data": [
    {
      "id": "<profile_id>",
      "userId": "<auth_user_id>",
      "name": "John Doe",
      "email": "john.doe@example.com",
      "bio": "",
      "avatar": "",
      "preferences": {
        "theme": "light",
        "notifications": {
          "email": true,
          "push": true
        }
      },
      "createdAt": "2025-12-30T00:00:00.000Z",
      "updatedAt": "2025-12-30T00:00:00.000Z"
    }
  ],
  "pagination": {
    "total": 1,
    "page": 1,
    "limit": 10,
    "totalPages": 1
  }
}

If you get 403 Not authorized, log in with an admin token (first registered user is admin).

Task Service (task-service)

Task service currently exposes simple endpoints:

List tasks

GET /tasks

curl:

curl "http://localhost:3002/tasks"

Create task

POST /tasks

Request body:

{
  "title": "Finish report",
  "description": "Complete the quarterly report",
  "userId": "<auth_user_id>"
}

Notes:

• On create, a message is published to RabbitMQ queue task_created.

curl:

curl -X POST "http://localhost:3002/tasks" \
  -H "Content-Type: application/json" \
  -d '{
    "title": "Finish report",
    "description": "Complete the quarterly report",
    "userId": "<auth_user_id>"
  }'

Notification Service (notification-service)

Notification service is intended to consume RabbitMQ messages (e.g., task_created).

Common Error Responses

400 Validation error

{
  "errors": [
    {
      "type": "field",
      "msg": "Password must be at least 8 characters",
      "path": "password",
      "location": "body"
    }
  ]
}

401 No token

{
  "message": "No token provided"
}

403 Invalid token / not authorized

{
  "message": "Not authorized to access this resource"
}

Tests

If tests exist for a service:

cd user-service
npm test

Notes & next steps

• Add rate limiting, CORS policy, and centralized logging for production.
• Consider adding refresh tokens and a token denylist if you need server-side logout.
• Consider improving inter-service communication so containers never depend on localhost URLs.