aiohttpvstreq
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.
treq is a Python library for making HTTP requests that provides a simple, convenient API for interacting with web services. It is inspired byt the popular requests library, but powered by Twisted asynchronous engine which allows promise based concurrency.
treq provides a simple, high-level API for making HTTP requests, including methods for GET, POST, PUT, DELETE, etc. It also allows for easy handling of JSON data, automatic decompression of gzipped responses, and connection pooling.
treq is a lightweight library and it's easy to use, it's a good choice for small to medium-sized projects where ease of use is more important than performance.
In web scraping treq isn't commonly used as it doesn't support HTTP2 but it's the only Twisted based HTTP client. treq is also based on callback/errback promises (like Scrapy) which can be easier to understand and maintain compared to asyncio's corountines.
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 twisted.internet import reactor
from twisted.internet.task import react
from twisted.internet.defer import ensureDeferred
import treq
# treq can be used with twisted's reactor with callbacks
response_deferred = treq.get(
"http://httpbin.org/get"
)
# or POST
response_deferred = treq.post(
"http://httpbin.org/post",
json={"key": "value"}, # JSON
data={"key": "value"}, # Form Data
)
# add callback or errback
def handle_response(response):
print(response.code)
response.text().addCallback(lambda body: print(body))
def handle_error(failure):
print(failure)
# this callback will be called when request completes:
response_deferred.addCallback(handle_response)
# this errback will be called if request fails
response_deferred.addErrback(handle_error)
# this will be called if request completes or fails:
response_deferred.addBoth(lambda _: reactor.stop()) # close twisted once finished
if __name__ == '__main__':
reactor.run()
#Note that treq can also be used with async/await:
async def main():
# content reads response data and get sends a get request:
print(await treq.content(await treq.get("https://example.com/")))
if __name__ == '__main__':
react(lambda reactor: ensureDeferred(main()))