上传多个文件 UploadFiles FastAPI

Question

例子

这是我的代码：

from typing import  List
from fastapi import FastAPI, File, UploadFile
import asyncio
import concurrent.futures

app = FastAPI()
@app.post("/send_images")
async def update_item(
    files: List[UploadFile] = File(...),
):
    return {"res": len(files)}

我向该服务器发送请求（这些特定网址仅作为示例）：

import requests
import os 
import json
import numpy as np
import time
import io
import httpx
import asyncio
from datetime import datetime
import pandas as pd

from random import shuffle
import pandas as pd
import urllib
import io
from PIL import Image
from matplotlib import pyplot as plt
import concurrent.futures

urls = ['https://sun9-63.userapi.com/c638920/v638920705/1a54d/xSREwpakJD4.jpg',
 'https://sun9-28.userapi.com/c854024/v854024084/1160d8/LDMVHYgguAw.jpg',
 'https://sun9-54.userapi.com/c854220/v854220084/111f66/LdcbEpPR6tg.jpg',
 'https://sun9-40.userapi.com/c841420/v841420283/4c8bb/Mii6GSCrmpo.jpg',
 'https://sun6-16.userapi.com/CPQpllJ0KtaArvQKkPsHTZDCupqjRJ_8l07ejA/iyg2hRR_kM4.jpg',
 'https://sun9-1.userapi.com/c638920/v638920705/1a53b/SMta6Bv-k7s.jpg',
 'https://sun9-36.userapi.com/c857332/v857332580/56ad/rJCGKFw03FQ.jpg',
 'https://sun6-14.userapi.com/iPsfmW0ibE8RsMh0k2lUFdRxHZ4Q41yctB7L3A/ajJHY3WN6Xg.jpg',
 'https://sun9-28.userapi.com/c854324/v854324383/1c1dc3/UuFigBF7WDI.jpg',
 'https://sun6-16.userapi.com/UVXVAT-tYudG5_24FMaBWTB9vyW8daSrO2WPFQ/RMjv7JZvowA.jpg']

os.environ['NO_PROXY'] = '127.0.0.1'

async def request_get_4(list_urls):
    async with httpx.AsyncClient() as client:
        r = httpx.post("http://127.0.0.1:8001/send_images", files={f'num_{ind}': el for ind, el in enumerate(list_urls)})
        print(r.text)
        return r

async def request_get_3(url):
    async with httpx.AsyncClient() as client:
        return await client.get(url)
    
from collections import defaultdict

async def main():
    start = datetime.now()
    tasks = [asyncio.create_task(request_get_3(url)) for url in urls[0:10]]
    result = await asyncio.gather(*tasks)
    
    data_to_send = []
    for ind, resp in enumerate(result):
        if resp.status_code == 200:
            image_bytes = io.BytesIO(resp.content)
            image_bytes.seek(0)
            data_to_send.append(image_bytes)
        
    end = datetime.now()
    print(result)
    print(len(data_to_send))

    batch_size = 2
    batch_num = len(data_to_send) // batch_size
    tasks = [asyncio.create_task(request_get_4(data_to_send[i * batch_size: (i+1) * batch_size])) for i in range(batch_num)]
    result = await asyncio.gather(*tasks)
    
    left_data = data_to_send[batch_size*(batch_num):]
    print(len(left_data))
    print(result)

asyncio.run(main())

我正在尝试加载 url 中包含的图像，然后形成批次并将它们发送到 FastAPI 服务器。但这不起作用。我收到以下错误：

{"detail":[{"loc":["body","files"],"msg":"field required","type":"value_error.missing"}]}

如何解决我的问题并能够通过 httpx 将多个文件发送到 FastAPI？

Answer 1

问题是 HTTPX 0.13.3 不支持多个文件上传，因为此参数需要字典，并且字典不能具有相同的键值。

我们可以使用这个拉取请求https://github.com/encode/httpx/pull/1032/files来解决这个问题（现在它也可以接受List[Tuple[str, FileTypes]]]）！

更新：这个问题现在已经解决了！

Update2：这里我展示了如何使用 httpx 来处理不同的请求：

async def request_post_batch(fastapi_url: str, url_content_batch: List[BinaryIO]) -> httpx.Response:
    """
    Send batch to FastAPI server.
    """
    async with httpx.AsyncClient(timeout=httpx.Timeout(100.0)) as client:
        r = await client.post(
            fastapi_url,
            files=[('bytes_image', url_content) for url_content in url_content_batch]
        )
        return r


async def request_post_logs(logstash_url: str, logs: List[Dict]) -> httpx.Response:
    """
    Send logs to logstash
    """
    async with httpx.AsyncClient(timeout=httpx.Timeout(100.0)) as client:
        r = await client.post(
            logstash_url,
            json=logs
        )
        return r