[Solved] Given this FastAPI code snippet, what will be the output when a file is uploaded?... Given this FastAPI code snippet, what will be the output when a file is uploaded? | FastAPI

FastAPI - File Handling

Given this FastAPI code snippet, what will be the output when a file is uploaded?

from fastapi import FastAPI, UploadFile
app = FastAPI()

@app.post('/upload')
async def upload(file: UploadFile):
    content = await file.read()
    return {'filename': file.filename, 'size': len(content)}

A{'filename': 'example.txt', 'size': 1000} if a 1000-byte file named example.txt is uploaded

BA syntax error because async functions cannot read files

CAn empty dictionary because file.read() returns None

DA runtime error because file.filename is not accessible

Step-by-Step Solution

Solution:

Step 1: Understand async file reading
The code uses await file.read() to read the uploaded file content asynchronously.
Step 2: Check returned dictionary
The function returns the filename and the size of the content in bytes, so for a 1000-byte file named example.txt, it returns that info.
Final Answer:
{'filename': 'example.txt', 'size': 1000} if a 1000-byte file named example.txt is uploaded -> Option A
Quick Check:
Async read + filename = correct output [OK]

Quick Trick: Async read returns bytes; filename is accessible [OK]

Common Mistakes:

MISTAKES

Thinking async can't read files
Assuming file.read() returns None
Believing file.filename is inaccessible

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More FastAPI Quizzes

Given this FastAPI code snippet, what will be the output when a file is uploaded?

Step 1: Understand async file reading

Step 2: Check returned dictionary

Final Answer:

Quick Check:

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