How to post a UploadFile object

[brandonbiggs]

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Example Code

from fastapi import UploadFile, FastAPI
from typing import Dict
import requests

app = FastAPI()

@app.post("/post_file/")
def post_file(file: UploadFile) -> Dict:
    contents = file.file.read()
    response = requests.post('https://example.com/post_file, files={'file': contents})
    return {'response': response}

Description

Hi!

How do I take a posted UploadFile object and post it to another API without writing it out and then rereading it? It seems like that should be possible? The second API is also taking an UploadFile object. The second API seems to work just fine. The second API will not be accessible post development, so I need to go through the first API and then post it to the second.

I have been trying to get a posted UploadFile, do some work with it, and then post it to another API. I'm trying to follow the documentation but I keep running into issues. Here's the documentation I was following - https://fastapi.tiangolo.com/tutorial/request-files/#uploadfile. My example code seems to be getting a 200 response code, but I am getting the following error which leads to an internal server error.

UnicodeDecodeError: 'utf-8' codec can't decode byte 0x9f in position 104: invalid start byte

I tried to use the await file.file.seek(0) instead of file.file.read() but I would get an error TypeError: object int can't be used in 'await' expression.

I'd prefer not to have to write the file and then reread it to send it, but if that's the only way I can do this, I can work with that.

Operating System

Linux, macOS

Operating System Details

No response

FastAPI Version

0.89.1

Python Version

Python 3.8.16

Additional Context

No response

[brandonbiggs]

I got it working.

For future reference if anyone else finds this:

@app.post("/post_file/")
def post_file(file: UploadFile) -> Dict:
    response = requests.post('https://example.com/post, files={'file': file.file})
    return response.json()