httpxvstreq
httpx is a fully featured HTTP client for Python 3, which provides sync and async APIs, and support for both HTTP/1.1 and HTTP/2. It is designed to be a replacement for the popular requests package, with the added benefit of being fully compatible with Python 3's async features.
One of the main features of httpx is its support for asynchronous programming. This means that it can send multiple requests at the same time, without blocking the execution of your program. This can lead to significant performance improvements, especially when working with many small requests, or when dealing with slow or unreliable network connections.
httpx also supports sending HTTP/2 requests, which allows for more efficient use of network resources and can result in faster page loads.
One of the strengths of httpx is the possibility of working on streaming mode for the response data. This means you can process the response as it comes in, instead of waiting for the entire response to be received. This is useful when working with large files, or when you need to process the data in real-time.
Additionally, httpx provides a number of other features that are common in modern HTTP clients, such as support for sending and receiving cookies, handling redirects, and working with multipart file uploads. It also include support for several well-known authentication modules like BasicAuth, DigestAuth, and BearerAuth.
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 httpx
# Just like requests httpx can be used directly
response = httpx.get("http://webscraping.fyi/")
response.status_code
200
response.text
"text"
response.content
b"bytes"
# HTTP2 needs to be enabled explicitly and is recommended for web scraping:
response = httpx.get("http://webscraping.fyi/", http2=True)
# httpx can automatically convert json responses to Python dictionaries:
response = httpx.get("http://httpbin.org/json")
print(response.json())
{'slideshow': {'author': 'Yours Truly', 'date': 'date of publication', 'slides': [{'title': 'Wake up to WonderWidgets!', 'type': 'all'}, {'items': ['Why <em>WonderWidgets</em> are great', 'Who <em>buys</em> WonderWidgets'], 'title': 'Overview', 'type': 'all'}], 'title': 'Sample Slide Show'}}
# for POST request it can ingest Python's dictionaries as JSON:
response = requests.post("http://httpbin.org/post", json={"query": "hello world"})
# or form data:
response = requests.post("http://httpbin.org/post", data={"query": "hello world"})
# persistent client can be established using Client object
# this allows to set default values and automatically track cookies
from httpx import Client
c = Client(headers={"User-Agent": "webscraping.fyi"}, http2=True)
c.get('http://httpbin.org/cookies/set/foo/bar')
print(c.cookies['foo'])
'bar'
print(c.get('http://httpbin.org/cookies').json())
{'cookies': {'foo': 'bar'}}
# for asynchronous requests AsyncClient must be used:
import asyncio
from httpx import AsyncClient
async def example_use():
async with AsyncClient(headers={"User-Agent": "webscraping.fyi"}) as client:
response = await client.get("http://httpbing.org/get")
# to schedule multiple requests concurrently use asyncio gather or as_completed
three_concurrent_responses = await asyncio.gather(
client.get("http://httpbing.org/get"),
client.get("http://httpbing.org/get"),
client.get("http://httpbing.org/get"),
)
asyncio.run(example_use())
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()))