File Storage Application

A secure file storage service built with Spring Boot that provides encrypted file upload and download capabilities using MongoDB GridFS.

Features

• Secure File Storage: Files are encrypted using AES-128 encryption before storage
• User Management: Complete user authentication and authorization system
• MongoDB GridFS: Efficient storage of large files using MongoDB GridFS
• RESTful API: Clean REST endpoints for file operations
• Metadata Tracking: Comprehensive file metadata including size, type, owner, and encryption status
• User-based Access Control: Files are associated with specific users for secure access
• Large File Support: Supports files up to 200MB in size
• JWT Authentication: Secure authentication using JSON Web Tokens

Technology Stack

• Java 17+
• Spring Boot 3.x
• Spring Data MongoDB
• MongoDB GridFS for file storage
• JWT for authentication
• AES-128 Encryption for file security
• Lombok for boilerplate reduction
• Log4j2 for logging
• AspectJ for cross-cutting concerns

Prerequisites

• Java 17 or higher
• MongoDB 4.0 or higher
• Maven 3.6 or higher

Installation

1. Clone the repository

   git clone <repository-url>
   cd file-storage

2. Configure MongoDB

   • Install MongoDB and ensure it's running on localhost:27017
   • Create a database named storage
   • Create an admin user with credentials: admin/password

3. Configure Application Properties

   Update src/main/resources/application.properties:

   # Application Configuration
   spring.application.name=file storage
   server.port=8081
   
   # MongoDB Configuration
   spring.data.mongodb.uri=mongodb://admin:password@localhost:27017/storage?authSource=admin
   spring.data.mongodb.database=storage
   spring.data.mongodb.gridfs.bucket=test
   
   # File Upload Configuration
   spring.servlet.multipart.max-file-size=200MB
   spring.servlet.multipart.max-request-size=200MB
   
   # JWT Configuration
   application.security.jwt.secret-key=your-secret-key-here
   application.security.jwt.expiration=86400000
   
   # PGP Keys (if using PGP encryption)
   secret.key.public=path/to/public.pgp
   secret.key.private=path/to/private.pgp
   secret.key.passkey=your-passkey

4. Build the application

   mvn clean install

5. Run the application

   mvn spring-boot:run

The application will start on http://localhost:8081

API Documentation

File Upload

Endpoint: POST /api/document/{user}

Description: Upload a file for a specific user

Request:

• Path Parameter: user - User identifier
• Body: Multipart form data with file field

Response:

{
  "id": "64a1b2c3d4e5f6789abcdef0",
  "fileName": "example.pdf"
}

Example:

curl -X POST \
  http://localhost:8081/api/document/user123 \
  -H 'Content-Type: multipart/form-data' \
  -F 'file=@/path/to/your/file.pdf'

File Download

Endpoint: GET /api/document/{user}/{id}

Description: Download a file by ID for a specific user

Request:

• Path Parameters:
  • user - User identifier
  • id - File identifier

Response: Binary file data with appropriate headers

Example:

curl -X GET \
  http://localhost:8081/api/document/user123/64a1b2c3d4e5f6789abcdef0 \
  -o downloaded-file.pdf

Security Features

File Encryption

• All files are automatically encrypted using AES-128 encryption before storage
• Encryption keys are generated dynamically for each application instance
• Files are decrypted on-the-fly during download

User Access Control

• Files are associated with specific users
• Only the file owner can download their files
• Unauthorized access attempts are rejected

JWT Authentication

• JWT tokens are used for secure authentication
• Configurable token expiration (default: 24 hours)
• Tokens include user information and permissions

File Storage Details

GridFS Integration

• Uses MongoDB GridFS for efficient large file storage
• Files are stored in chunks for optimal performance
• Metadata is stored alongside file content

File Metadata

Each stored file includes comprehensive metadata:

• fileName: Original filename
• fileSize: File size in bytes
• fileType: MIME type
• owner: User ID who uploaded the file
• isEncrypted: Encryption status (always true)
• isCompressed: Compression status
• version: File version number
• duplicateCount: Number of duplicates

User Management

The application includes a complete user management system:

User Features

• User registration and authentication
• Role-based access control
• Account status management (enabled, locked, expired)
• Unique bucket assignment per user

User Roles

• Configurable role system
• Role-based permissions for file access

Development

Project Structure

src/
├── main/
│   ├── java/com/file/storage/
│   │   ├── configuration/     # Application configuration
│   │   ├── dao/              # Data Access Objects
│   │   ├── dto/              # Data Transfer Objects
│   │   ├── helper/           # Utility classes
│   │   ├── mapper/           # Object mapping
│   │   ├── pojo/             # Plain Old Java Objects
│   │   ├── repository/       # Data repositories
│   │   ├── service/          # Business logic
│   │   └── web/rest/         # REST controllers
│   └── resources/
│       ├── application.properties
│       └── secret/           # PGP keys
└── test/                     # Test classes

Running Tests

mvn test

Building for Production

mvn clean package -Pprod

Configuration

Environment Profiles

• dev: Development profile with debug logging
• prod: Production profile with optimized settings

Key Configuration Properties

Property	Description	Default
server.port	Application port	8081
spring.data.mongodb.uri	MongoDB connection string	mongodb://admin:password@localhost:27017/storage?authSource=admin
spring.servlet.multipart.max-file-size	Maximum file upload size	200MB
application.security.jwt.expiration	JWT token expiration time	86400000 (24 hours)

Monitoring and Logging

Logging Configuration

• Uses Log4j2 for structured logging
• Debug logging for AOP and security components
• Request/response logging for file operations

Health Monitoring

The application includes Spring Boot Actuator endpoints for monitoring:

• /actuator/health - Application health status
• /actuator/info - Application information

Troubleshooting

Common Issues

1. MongoDB Connection Issues

   • Verify MongoDB is running
   • Check connection credentials in application.properties
   • Ensure the storage database exists

2. File Upload Failures

   • Check file size limits (max 200MB)
   • Verify user exists in the system
   • Check disk space and MongoDB storage

3. Authentication Issues

   • Verify JWT configuration
   • Check token expiration settings
   • Ensure user credentials are correct

Error Codes

• 404: File or user not found
• 401: Unauthorized access
• 413: File too large
• 500: Internal server error (check logs)

Contributing

1. Fork the repository
2. Create a feature branch
3. Commit your changes
4. Push to the branch
5. Create a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

For support and questions, please contact the development team or create an issue in the repository.