User Management System

This project demonstrates a microservice architecture designed to manage user registration, authentication, password management, and communication through a notification service that includes email and SMS features for sending OTPs and other information to users. The system uses an API Gateway for routing client requests to the respective services.

Architecture Overview

The system is structured into multiple microservices, each handling specific functionalities. The core components of the architecture are:

1. API Gateway

The API Gateway acts as the entry point for all requests. It routes client requests to the appropriate microservice based on the request type:

• Routes requests to other services.
• Validates tokens via the Authentication Service (Private API).

2. User Service

The User Service manages user-related operations:

• Register: Allows new user registration.
• Update Profile: Enables users to update their profile information.
• Get User Info: Retrieves user information for authenticated users.

3. Authentication Service

The Authentication Service is responsible for handling:

• Login: Authenticates a user with credentials.
• Refresh Token: Provides a new JWT token to extend the session.
• Validate Token: Verifies token authenticity for secure endpoints.

4. Password Service

The Password Service provides functionality for password recovery and reset:

• Forgot Password: Initiates password recovery through email/SMS.
• Reset Password: Allows the user to set a new password.

5. OTP Service

The OTP Service generates and validates one-time passwords (OTPs) for secure transactions:

• Generate OTP: Issues a new OTP for verification.
• Validate OTP: Confirms the OTP provided by the user.

6. Notification Service

The Notification Service handles notifications and alerts:

• Send Email: Sends emails to the user for account-related notifications.
• Send Mobile SMS: Sends SMS messages to the user's phone for critical alerts like OTPs.

7. Token Validation

A Private API is used to validate tokens securely. This ensures that only authenticated users can access specific services.

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Communication Flow

1. Client-Server Communication (REST API)

• Clients (web or mobile apps) communicate with the system through the API Gateway via RESTful APIs.
• The API Gateway acts as the main entry point, ensuring all requests are authenticated and routed to the relevant microservices.

2. Service-to-Service Communication (gRPC)

• Once a request reaches the API Gateway, it is forwarded to the corresponding microservices via gRPC. This high-performance communication protocol allows the services to efficiently handle interactions between themselves.

Each microservice communicates with others using gRPC for internal service communication:

• The User Service, Authentication Service, Password Service, OTP Service, and Notification Service interact with each other for tasks such as user existence checks, sending OTPs, and validating tokens.

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Interaction Flow

1. The Client sends requests to the API Gateway.
2. Based on the request type (e.g., registration, login, profile update, password reset), the API Gateway forwards the request to the appropriate microservice.
3. For operations requiring authentication, the API Gateway validates the token via the Authentication Service.
4. Services communicate with each other using gRPC for secure and fast interaction.

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Key Features

• JWT-based Authentication: Secure login and token-based session management.
• gRPC Communication: High-performance inter-service communication.
• REST API: Client-server communication using REST APIs.
• OTP-based Security: Secure sensitive operations with one-time passwords.
• Notification Service: Email and SMS integration for user notifications.

Technologies Used

• Spring Boot: To build each microservice.
• gRPC: For internal service-to-service communication.
• JWT: For authentication and session management.
• REST APIs: For client-server communication.
• SMTP and SMS Gateway: To send email and SMS notifications.
• Docker/Kubernetes: (Optional) For containerization and orchestration.

Getting Started

1. Clone the repository:

   git clone https://github.com/ayeujjawalsingh/User-Management-System.git

2. Build and run the services:

   cd user-management-system
   mvn clean install
   docker-compose up -d

3. Access the services via the API Gateway:

   • Register: POST /user/register
   • Update Profile: PUT /user/update-profile
   • Get User Info: GET /user/get-user-info
   • Login: POST /auth/login
   • Validate Token: POST /auth/validate-token
   • Refresh Token: POST /auth/refresh-token
   • Forgot Password: POST /password/forgot-password
   • Reset Password: POST /password/reset-password
   • Generate OTP: POST /otp/generate-otp
   • Validate OTP: POST /otp/validate-otp
   • Send Email: POST /notif/send-email
   • Send SMS: POST /notif/send-sms