How to Upload Files using FastAPI

In FastAPI, you can easily handle file uploads using the File data type from the fastapi module. You'll also need to use a library like python-multipart for parsing multipart/form-data requests.

Follow these steps to upload files in FastAPI:

1. Install fastapi:

pip install fastapi

2. Install python-multipart:

pip install python-multipart

3. Install aiofiles:

pip install aiofiles

The aiofiles library helps to upload files asynchronously.

4. Create and endpoint to handle file uploads:

from fastapi import FastAPI, File, UploadFile
import uvicorn
import aiofiles
from typing import List

app = FastAPI()

@app.post("/single-file")
async def upload_single_file(file: UploadFile = File(...)):
    print("filename = ", file.filename) # getting filename
    destination_file_path = "/home/abc/videos/"+file.filename # location to store file
    async with aiofiles.open(destination_file_path, 'wb') as out_file:
        while content := await file.read(1024):  # async read file chunk
            await out_file.write(content)  # async write file chunk

    return {"Result": "OK"}


@app.post("/multiple-files")
async def upload_multiple_files(files: List[UploadFile] = File(...)):
    for file in files:
        destination_file_path = "/home/fm-pc-lt-46/Music/"+file.filename #output file path
        async with aiofiles.open(destination_file_path, 'wb') as out_file:
            while content := await file.read(1024):  # async read file chunk
                await out_file.write(content)  # async write file chunk
    return {"Result": "OK", "filenames": [file.filename for file in files]}


if __name__ == '__main__':
    uvicorn.run(app, host='127.0.0.1', port=8005)
    print("running")

In this code example, we define two endpoints: /single-upload/, which accepts a POST request with an UploadFile parameter, and /multiple-uploads/, which accepts a POST request with a list of UploadFile parameter. The uploaded files are then processed and saved to the server with their original filenames.

5. Run Application:

python main.py