File Upload/Download API

A FastAPI-based REST API for uploading, downloading, and managing files with SQLite database for metadata storage.

Features

• Upload files with size validation
• Download files by ID
• List all uploaded files
• Get detailed file metadata
• Delete files
• Health check endpoint
• OpenAPI documentation

Prerequisites

• Python 3.8+
• pip (Python package manager)

Installation

1. Clone the repository:

   git clone <repository-url>
   cd fileuploaddownloadapi
   

2. Install dependencies:

   pip install -r requirements.txt
   

3. Run database migrations:

   alembic upgrade head
   

Usage

Running the Server

Start the application with uvicorn:

uvicorn main:app --host 0.0.0.0 --port 8000 --reload

The API will be available at http://localhost:8000.

API Documentation

Interactive API documentation is available at:

• Swagger UI: http://localhost:8000/docs
• ReDoc: http://localhost:8000/redoc

API Endpoints

File Operations

• Upload a file

  • POST /api/v1/files/
  • Request: Form data with a file
  • Response: File metadata with download URL

• List all files

  • GET /api/v1/files/
  • Response: Array of file metadata objects

• Get file metadata

  • GET /api/v1/files/{file_id}
  • Response: File metadata object

• Download a file

  • GET /api/v1/files/{file_id}/download
  • Response: File content as a binary stream

• Delete a file

  • DELETE /api/v1/files/{file_id}
  • Response: No content (204)

Health Check

• Health check endpoint
  • GET /health
  • Response: {"status": "healthy"}

Root Endpoint

• API Information
  • GET /
  • Response: Basic API information and links

Configuration

The API uses environment variables for configuration:

Variable	Description	Default Value
PROJECT_NAME	Name of the project	"File Upload Download API"
MAX_FILE_SIZE	Maximum allowed file size in bytes	10485760 (10MB)
STORAGE_BASE_DIR	Base directory for all storage	"./storage"
FILE_STORAGE_DIR	Directory for storing uploaded files	"{STORAGE_BASE_DIR}/files"
DB_DIR	Directory for the SQLite database	"{STORAGE_BASE_DIR}/db"
SQLALCHEMY_DATABASE_URL	Full database connection URL	"sqlite:///{DB_DIR}/db.sqlite"

File Storage

By default, files are stored in the ./storage/files directory. File metadata is stored in a SQLite database at ./storage/db/db.sqlite.

Storage in Containerized Environments

When running in a containerized environment like Docker, you should handle storage paths carefully:

1. Using Volume Mounts: Mount a persistent volume to the storage directory:

   docker run -v /host/path/to/storage:/app/storage your-image-name
   

2. Using Environment Variables: Configure storage locations with environment variables:

   docker run -e STORAGE_BASE_DIR=/data -v /host/path/to/data:/data your-image-name
   

3. Pre-creating Directories: Ensure directories exist with proper permissions:

   mkdir -p ./storage/files ./storage/db
   chmod 777 ./storage/files ./storage/db  # For development only
   

Note

: The application will continue running even if it cannot create storage directories, but file operations will fail. This allows the application to start and serve documentation even if storage is not properly configured.

Development

Project Structure

fileuploaddownloadapi/
├── app/
│   ├── api/
│   │   └── v1/
│   │       ├── api.py
│   │       └── endpoints/
│   │           └── files.py
│   ├── core/
│   │   └── config.py
│   ├── db/
│   │   ├── base.py
│   │   ├── session.py
│   │   └── migrations/
│   │       └── versions/
│   │           └── 001_create_files_table.py
│   ├── models/
│   │   └── file.py
│   ├── schemas/
│   │   └── file.py
│   └── services/
│       └── file_service.py
├── storage/
│   ├── db/
│   └── files/
├── alembic.ini
├── main.py
└── requirements.txt

Running Migrations

# Create a new migration
alembic revision -m "description"

# Apply all migrations
alembic upgrade head

# Rollback a migration
alembic downgrade -1

# Check current migration version
alembic current

License

MIT License