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aiohttpvsmechanize

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429.2 million (month) Jul 26 2019 3.13.5(2026-03-31 21:56:30 ago)
4,440 8 6 MIT
Jul 25 2009 213.1 thousand (month) 2.14.0(2025-01-05 18:30:46 ago)

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.

Mechanize is a Ruby library for automating interaction with websites. It automatically stores and sends cookies, follows redirects, and can submit forms — making it behave like a web browser without needing an actual browser engine.

Key features include:

  • Automatic cookie management Stores cookies received from servers and sends them back on subsequent requests, maintaining session state across multiple pages.
  • Form handling Can find, fill in, and submit HTML forms programmatically. Supports text inputs, selects, checkboxes, radio buttons, and file uploads.
  • Link following Navigate through pages by clicking links using their text content, CSS selectors, or href patterns.
  • History and back/forward Maintains a browsing history, allowing you to go back and forward through visited pages.
  • HTTP authentication Supports basic and digest HTTP authentication.
  • Proxy support Can route requests through HTTP proxies.
  • Redirect handling Automatically follows HTTP redirects (configurable).

Mechanize is one of the oldest and most established web interaction libraries in Ruby. It is best suited for scraping traditional server-rendered websites with forms and multi-page workflows. For JavaScript-heavy sites, a browser automation tool like Selenium or Playwright is recommended instead.

Highlights


asynciowebsocketshttp2http-servermulti-partresponse-streaminghttp-proxy
popularproduction

Example Use


```python 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()) ```
```ruby require 'mechanize' agent = Mechanize.new # Navigate to a page page = agent.get('https://example.com') puts page.title # Find and click a link page = page.link_with(text: 'Products').click # Extract data from the page page.search('.product').each do |product| name = product.at('.name').text price = product.at('.price').text puts "#{name}: #{price}" end # Fill in and submit a login form login_page = agent.get('https://example.com/login') form = login_page.form_with(action: '/login') form['username'] = 'user@example.com' form['password'] = 'password123' dashboard = agent.submit(form) # Cookies are maintained automatically puts dashboard.title # "Dashboard" # Download a file agent.get('https://example.com/report.csv').save('report.csv') ```

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