aiohttpvscurl-cffi
aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. It provides a simple API for making HTTP requests and handling both client and server functionality. Like the requests package, aiohttp is designed to be easy to use and handle many of the low-level details of working with HTTP.
The main benefit of aiohttp over requests is that it is built on top of the asyncio library, which means that it can handle many requests at the same time without blocking the execution of your program. This can lead to significant performance improvements when making many small requests, or when dealing with slow or unreliable network connections.
aiohttp provides both client and server side functionality, so you can use it to create web servers and handle client requests in a non-blocking manner. It also supports WebSocket protocol, so it can be used for building real-time application like chat, game, etc.
aiohttp also provide several features for handling connection errors, managing timeouts, and client sessions. It also provide similar features like requests package like redirect handling, cookies, and support for several authentication modules.
You can install aiohttp via pip package manager:
pip install aiohttp
In terms of API design, aiohttp is similar to requests and thus should be familiar to anyone who has used the requests library, but it provides an async with block to manage the context of the connection and used await statement to wait for the result.
It''s worth noting that aiohttp is built on top of asyncio and is designed to be used in Python 3.5 and above. It provides the same functionality as httpx but it is specifically built for the asyncio framework.
Curl-cffi is a Python library for implementing curl-impersonate which is a
HTTP client that appears as one of popular web browsers like:
- Google Chrome
- Microsoft Edge
- Safari
- Firefox
Unlike requests and httpx which are native Python libraries, curl-cffi uses cURL and inherits it's powerful features
like extensive HTTP protocol support and detection patches for TLS and HTTP fingerprinting.
Using curl-cffi web scrapers can bypass TLS and HTTP fingerprinting.
Highlights
Example Use
import asyncio
from aiohttp import ClientSession, WSMsgType
# aiohttp only provides async client so we must use a coroutine:
async def run():
async with ClientSession(headers={"User-Agent": "webscraping.fyi"}) as session:
# we can use the session to make requests:
response = await session.get("http://httpbin.org/headers")
print(response.status)
# note: to read the response body we must use await:
print(await response.text())
# aiohttp also comes with convenience methods for common requests:
# POST json
resp = await session.post("http://httpbin.org/post", json={"key": "value"})
# POST form data
resp = await session.post("http://httpbin.org/post", data={"key": "value"})
# decode response as json
resp = await session.get("http://httpbin.org/json")
data = await resp.json()
print(data)
# aiohttp also supports websocket connections
# which can be used to scrape websites that use websockets:
async with session.ws_connect("http://example.org/ws") as ws:
async for msg in ws:
if msg.type == WSMsgType.TEXT:
if msg.data == "close cmd":
await ws.close()
break
else:
await ws.send_str(msg.data + "/answer")
elif msg.type == WSMsgType.ERROR:
break
asyncio.run(run())
from curl_cffi import requests
response = requests.get('https://httpbin.org/json')
print(response.json())
# or using sessions
session = requests.Session()
response = session.get('https://httpbin.org/json')
# also supports async requests using asyncio
import asyncio
from curl_cffi.requests import AsyncSession
urls = [
"http://httpbin.org/html",
"http://httpbin.org/html",
"http://httpbin.org/html",
]
async with AsyncSession() as s:
tasks = []
for url in urls:
task = s.get(url)
tasks.append(task)
# scrape concurrently:
responses = await asyncio.gather(*tasks)
# also supports websocket connections
from curl_cffi.requests import Session, WebSocket
def on_message(ws: WebSocket, message):
print(message)
with Session() as s:
ws = s.ws_connect(
"wss://api.gemini.com/v1/marketdata/BTCUSD",
on_message=on_message,
)
ws.run_forever()