Mini Projects: Banking App, Todo API, File Uploader, Blog Backend

Here’s a breakdown of the mini projects that can be done using Spring Boot, covering a variety of use cases to help you practice and gain proficiency:

1. Banking App

Project Overview: This project involves creating a basic banking system where users can create accounts, view balances, make deposits and withdrawals, and transfer money between accounts.

Key Features:

• User registration and authentication using JWT.
• Account creation with user details (name, email, etc.).
• Balance inquiry and account details view.
• Transfer money between accounts.
• Deposit and withdraw funds from an account.
• Transaction history for each account.

Key Technologies:

• Spring Boot: For the backend.
• Spring Security: For user authentication.
• MySQL/PostgreSQL: To store user accounts and transaction details.
• JWT: For stateless authentication.

Steps:

1. Set up Spring Boot application with Spring Data JPA and Spring Security.
2. Create User and Account models.
3. Implement Deposit, Withdrawal, Transfer, and Balance Check services.
4. Implement Transaction history to track deposits, withdrawals, and transfers.
5. Secure endpoints with JWT authentication.

2. Todo API

Project Overview: This is a simple To-Do List API where users can register, create tasks, update task status, delete tasks, and view their tasks.

Key Features:

• User registration and authentication with JWT.
• CRUD operations for tasks (create, read, update, delete).
• Mark tasks as completed or pending.
• Pagination and sorting for tasks.
• Task priority levels (low, medium, high).

Key Technologies:

• Spring Boot: For the backend.
• Spring Security: For user authentication.
• Spring Data JPA: To store tasks in a database.
• MySQL/PostgreSQL: For database management.

Steps:

1. Set up a Spring Boot project with JWT authentication and Spring Data JPA.
2. Create User and Task models.
3. Implement CRUD operations for tasks.
4. Implement sorting and pagination for tasks.
5. Secure the API with JWT authentication.

3. File Uploader

Project Overview: This project involves building an application that allows users to upload files (images, documents, etc.) to the server and manage them.

Key Features:

• User authentication and authorization using JWT.
• Support for uploading multiple file types (images, PDFs, etc.).
• Store file metadata (name, size, type).
• Ability to view and download uploaded files.
• Ability to delete uploaded files.

Key Technologies:

• Spring Boot: For the backend.
• Spring Security: For JWT-based authentication.
• Spring Web: For file handling.
• MySQL/PostgreSQL: To store file metadata.

Steps:

1. Set up a Spring Boot application with JWT authentication.
2. Create endpoints to handle file uploads and store the file metadata in the database.
3. Implement functionality for file viewing and downloading.
4. Secure API endpoints with JWT.
5. Add validation for file types and size limits.

4. Blog Backend

Project Overview: This project is a simple backend for a blog where users can register, create blog posts, and comment on posts. The system should allow users to like and dislike posts.

Key Features:

• User authentication and JWT-based session management.
• CRUD operations for blog posts.
• Commenting system on each blog post.
• Like and dislike posts functionality.
• Pagination and sorting of posts.

Key Technologies:

• Spring Boot: For the backend.
• Spring Security: For authentication using JWT.
• Spring Data JPA: For data persistence (blog posts, comments, etc.).
• MySQL/PostgreSQL: For storing data.

Steps:

1. Set up a Spring Boot application with JWT authentication.
2. Create models for User, Post, and Comment.
3. Implement CRUD functionality for Posts and Comments.
4. Implement the like/dislike functionality.
5. Implement pagination and sorting for blog posts.
6. Secure all the API endpoints with JWT authentication.

General Steps for All Projects:

1. Set up Spring Boot Project:
   • Use Spring Initializr to generate the base Spring Boot project.
   • Add dependencies like Spring Web, Spring Data JPA, Spring Security, JWT (for authentication), MySQL/PostgreSQL, and Lombok if required.
2. Create Models:
   • Define entities for your database, such as User, Post, Task, etc.
3. Create Repositories:
   • Use Spring Data JPA repositories to interact with the database.
4. Service Layer:
   • Implement business logic (CRUD operations, authentication, etc.) in the Service classes.
5. Controller Layer:
   • Create REST controllers to expose the APIs and map them to the service layer.
6. JWT Authentication:
   • Implement JWT authentication for security.
7. Test the APIs:
   • Use tools like Postman or Swagger to test your APIs.

These mini projects provide hands-on experience with essential Spring Boot concepts and demonstrate the ability to build real-world applications. By completing them, you’ll gain a deeper understanding of working with databases, authentication, and building RESTful APIs with Spring Boot.