Java -> FastAPI File Upload Demo

Overview

This project demonstrates how to upload a file from Java client to a Python FastAPI server using 'multipart/form-data'.

It is a minimal working example for:

• Java HTTP file upload
• FastAPI file receving
• Cross-language communication (Java -> Python)

Project Structure

|---java-client/
| |---CallAPI.java
| |---test.txt
|
|---python-server/
| |---main.py
| |---test.txt
|
|---.gitignore
|___README.md

Quick Start

1.Start Python Server

Bash
cd python-server
uvicorn main:app --reoad --port :8000
// server will run at:
// http://127.0.0.1:8000

2.Run Java Client

Bash
cd java-client
javac CallAPI.java
java CallAPI test.txt

Response

Response: {"filename":"test.txt","size":4}

Key Concepts

• mulipart/form-data encoding
• Boundary separation in HTTP
• File streaming (Java -> Python)
• FastAPI Uplodafile

Notes

• Do not upload large files without streaming (memory risk)
• .class and pycache are ignore via .gitignore
• This is a minimal demo, not production-ready

Future Improvements

• Add extra parameters (e.g., modal_type)
• Support video/audio upload
• Integrate DeepFake detection model
• Use streaming instead of full file read

Author

• Elvis Yan