REST Lab Microservices Application

A containerized, microservices-based application consisting of a React frontend, distinct backend services for Authentication, Payments, and Notifications, along with a MongoDB database and a RabbitMQ message broker.

3. Access the application:
   • Frontend Application: http://localhost:3000
   • RabbitMQ Management UI: http://localhost:15672 (Default login: guest / guest)
   • Auth Service API: http://localhost:5001
   • Payment Service API: http://localhost:5002
   • Admin Dashboard: http://localhost:3000/dashboard.html

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Here is the exact step-by-step test to do this:

1. Stop the Notification Service: Run this command in your terminal:

docker stop notification-service

2. Generate some Messages (Produce): Go to Thunder Client and send a few POST requests to your Payment Service (http://localhost:5002/api/payments). Send it 3 or 4 times.

• Your API will still respond with success because the payment service and RabbitMQ are still running.

3. Watch the Queue Pile Up: Open the RabbitMQ Management UI in your browser: http://localhost:15672

• Go to the Queues tab.
• Look at your queue. You will now see 3 or 4 messages sitting in the "Ready" column. They aren't resolving because the consumer is turned off!

4. Start the Service and Watch it Drain (Consume): Now, turn the notification service back on to see RabbitMQ do its job:

docker start notification-service

If you look at the RabbitMQ UI again (or check the logs with docker logs notification-service), you will see it instantly process all the backlogged messages, and the queue will drop back down to 0.

This is the exact magic of message brokers—they ensure you never lose data even if a background service crashes or goes offline for maintenance!

API Testing with Thunder Client (VS Code)

You can easily test the REST APIs using Thunder Client in VS Code. Below are examples of POST, GET, PUT, and DELETE requests for the Auth Service.

Manual Request Examples

1. POST (Login / Create User)

• Method: POST
• URL: http://localhost:5001/auth/login
• Headers: Content-Type: application/json
• Body (JSON):

  {
    "name": "John Doe",
    "email": "johndoe@example.com",
    "password": "mypassword123"
  }

  (Note: Copy the _id from the response, you will need it for the GET, PUT, and DELETE requests below!)

2. GET (Retrieve All Users)

• Method: GET
• URL: http://localhost:5001/auth/users

3. GET (Retrieve a Single User)

• Method: GET
• URL: http://localhost:5001/auth/users/USER_ID_HERE

4. PUT (Update User Details)

• Method: PUT
• URL: http://localhost:5001/auth/users/USER_ID_HERE
• Headers: Content-Type: application/json
• Body (JSON):

  {
    "name": "John Smith",
    "email": "john.smith.updated@example.com"
  }

5. DELETE (Remove a User)

• Method: DELETE
• URL: http://localhost:5001/auth/users/USER_ID_HERE

Useful Docker Commands

Stop the application gracefully:

docker compose down

Stop the application and wipe the database (useful for fresh starts):

docker compose down -v 

View logs for a specific service:

docker logs rest-auth
# or
docker logs rest-payment