🚀 Microservices Based Note Taking Application

⏳ description

This is a simple note taking application that is built using microservices architecture. The application consists of two services, the notes-service and the users-service. The notes-service is responsible for managing notes and the users-service is responsible for managing users and authentication. The notes-service and the users-service communicate with each other using REST APIs And message broker (RabbitMQ) , every Microservice has its own database and two services are connected to Nginx as a api gateway for routing the requests.

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🚀 How to run the Infrastructure

• Clone the repository
• Run start.sh script to start the application the flow of script
  • Check if docker is installed or not
  • Check if docker-compose is installed or not
  • Start the application using docker-compose
  • Check if the application is started successfully or not by check status code of end point of nginx getway
• docker compose will start the following services
  • users-service-db : MySQL database for the users-service
  • notes-service-db : MySQL database for the notes-service
  • auth-service : Laravel service for user management and authentication
  • notes-service : Laravel service for notes management
  • notes-service-worker : Laravel worker service for handling delete user event
  • nginx : Nginx service as an API gateway
  • rabbitmq : RabbitMQ service as a message broker

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🔦 Postman API Documentation

• path: ApiGetway + Microservice + Route

Auth Service

• Create User : APIGetway + '/auth/api/register' [POST]
• Login User : APIGetway + '/auth/api/login' [POST]
• Check Authenticated User : APIGetway + '/auth/api/check' [GET]
• Delete User : APIGetway + '/auth/api/delete' [DELETE]

Notes Service

• Create Note : APIGetway + '/note/api/note' [POST]
• Get All Notes : APIGetway + '/note/api/note' [GET]
• Get Single Note : APIGetway + '/note/api/note/{id}' [GET]
• Update Note : APIGetway + '/note/api/note/{id}' [PUT]
• Delete Note : APIGetway + '/note/api/note/{id}' [DELETE]

📝 Features

• User registration , login and authentication using JWT
• Create, Read, Update and Delete notes
• Get all notes of a user
• Get a single note of a user

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⚡ Flow of the application

• User registers throw the auth-service Service and gets a JWT token
• User Creates a note throw the notes-service Service and sends the JWT token in the header
• The notes-service Service validates the JWT token Throw send REST API request to the auth-service Service
• The auth-service Service validates the JWT token and sends the response to the notes-service Service
• The notes-service Service creates the note in the database and returns the response to the user
• If User deletes his account throw the auth-service Service, auth-service Service sends an event to the notes-service Service to delete all notes of the user throw RabbitMQ message broker

🤿 Important questions ?

Why we don't use a message broker to communicate between the auth-service and the notes-service in authentication process ?

• Because note-service needs to validate the JWT token in every request and it's not a good idea to use a message broker in this case because it will make the process slower and more complex because note-service want to response to the user as fast as possible so if we use a message broker it will make the process slower because the note-service will send event contains the JWT token and identification number or session id to identify current user and will waint time untill the auth-service validate the JWT token and send the response to the note-service throw the message broker and then the note-service must in this case to validate all events that it receives from the auth-service throw the message broker and check which event is related to the current user and then it will respond to the user so it's not a good idea to use a message broker in this case, let us take example to worst case we have 4 requested in same time so php application server like (fpm-php or FrankenPHP ) open 4 threads to handle the requests and the 4 threads will send 4 events to the message broker and the message broker will send the 4 events to the auth-service and the auth-service will validate the JWT token and send the response to the message broker and the message broker will send the response to the note-service and the note-service will validate the response and send the response to the user so in this case the process will be slower and more complex and the note-service will validate the response 4 times to check which response is related to the current user so it's not a good idea to use a message broker in this case in this case service or instance to service is stateful because the note-service must validate the response and check which response is related to the current user so it's not a good idea to use a message broker in this case

Why we use a message broker to communicate between the auth-service and the notes-service in delete user process ?

• Because auth-service wants to delete all notes of the user when the user deletes his account so it's a good idea to use a message broker in this case because the auth-service doesn't need to wait for the response of the notes-service to delete the user because the auth-service doesn't need to know if the notes-service deleted the user notes or not so it's a good idea to use a message broker in this case because the auth-service can send the event to the message broker and the message broker will send the event to the notes-service and the notes-service will delete the user notes and the notes-service doesn't need to send a response to the auth-service so it's a good idea to use a message broker in this case because the auth-service doesn't need to wait for the response of the notes-service to delete the user notes so in this case service or instance to service is stateless because the auth-service doesn't need to wait for the response of the notes-service to delete the user notes so it's a good idea to use a message broker in this case

🧪 Testing

We make Feature tests for the auth-service and the notes-service to test the API endpoints and the authentication process and the notes management process

Auth Service

• Register User
• Login User
• Check Authenticated User
• Delete User

How to run the tests

• Go to the auth-service directory
• Run php artisan test

Notes Service

• Create Note
• Get All Notes
• Get Single Note
• Update Note
• Delete Note

How to run the tests

• Go to the notes-service directory
• Run php artisan test

🔬 Testing Pipeline using Github Action

i make a Github Action workflow to run the tests of the auth-service and the notes-service every time we pull request to the main branch , i make separate testing pipline workflow for the auth-service and the notes-service to run the tests of the auth-service and the notes-service separately based on the changes that we made in the code of the auth-service or the notes-service so we can know which service has the issue in the code and we can fix it easily

💉 Future Plans

• Add more features to the application like sharing notes between users
• Add end to end testing to the application whcih test the application as a whole in every new release
• Add more microservices to the application like files-service to manage files and notifications-service to manage notifications
• Scale the application by adding more instances of the services and use a load balancer to distribute the requests between the instances
• Use Kubernetes to manage the application and scale the application and make it more reliable and secure
• Use Redis as a cache to cache the requests and make the application faster

🛠️ Technologies

• Laravel
• MySQL
• RabbitMQ
• Nginx
• Docker
• Github Actions