How can I send an HTTP request from my FastAPI app to another site?

Question

I am trying to send 100 requests at a time to a server http://httpbin.org/uuid using the following code snippet

from fastapi import FastAPI
         


        

Answer 1

requests is a synchronous library. You need to use an asyncio-based library to make hundreds of requests asynchronously.

aiohttp example

from fastapi import FastAPI
from time import time
import aiohttp
import asyncio

app = FastAPI()

URL = "http://httpbin.org/uuid"


async def main(session):
    async with session.get(URL) as response:
        return await response.text()


async def task():
    async with aiohttp.ClientSession() as session:
        tasks = [main(session) for i in range(100)]
        result = await asyncio.gather(*tasks)
        print(result)


@app.get('/')
async def f():
    start = time()
    await task()
    print("time: ", time() - start)

Output

['{\n  "uuid": "65c454bf-9b12-4ba8-98e1-de636bffeed3"\n}\n', '{\n  "uuid": "03a48e56-2a44-48e3-bd43-a0b605bef359"\n}\n',...
time:  0.5911855697631836

httpx example

import uvicorn
from fastapi import FastAPI
from time import time
import httpx
import asyncio

app = FastAPI()

URL = "http://httpbin.org/uuid"


async def main(client):
    response = await client.get(URL)
    return response.text


async def task():
    async with httpx.AsyncClient() as client:
        tasks = [main(client) for i in range(100)]
        result = await asyncio.gather(*tasks)
        print(result)


@app.get('/')
async def f():
    start = time()
    await task()
    print("time: ", time() - start)