基于asyncio的轻量异步微爬虫框架
Posted 明柳梦少
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安装
一个异步网络抓取微框架，用asyncio和aiohttp编写，旨在使抓取网址尽可能方便。
# For Linux & Mac
pip install -U aspider[uvloop]
# For Windows
pip install -U aspider
# New features
pip install git+https://github.com/howie6879/aspider用法
请求和响应
我们提供了一个简单request的网址方式，并返回一个友好的response：
import asyncio
from aspider import Request
request = Request("https://news.ycombinator.com/")
response = asyncio.get_event_loop().run_until_complete(request.fetch())
# Output
# [2018-07-25 11:23:42,620]-Request-INFO <GET: https://news.ycombinator.com/>
# <Response url[text]: https://news.ycombinator.com/ status:200 metadata:{}>javascript支持：
request = Request("https://www.jianshu.com/", load_js=True)
response = asyncio.get_event_loop().run_until_complete(request.fetch())
print(response.body)使用时需要注意load_js，它会下载最新版本的Chromium（~100MB）。这曾发生过一次。
项目
我们来看一个Item用于提取目标数据的快速示例。首先将以下内容添加到demo.py中：
import asyncio
from aspider import AttrField, TextField, Item
class HackerNewsItem(Item):
target_item = TextField(css_select='tr.athing')
title = TextField(css_select='a.storylink')
url = AttrField(css_select='a.storylink', attr='href')
async def clean_title(self, value):
return value
items = asyncio.get_event_loop().run_until_complete(HackerNewsItem.get_items(url="https://news.ycombinator.com/"))
for item in items:
print(item.title, item.url)执行： python demo.py
Notorious ‘Hijack Factory’ Shunned from Web https://krebsonsecurity.com/2018/07/notorious-hijack-factory-shunned-from-web/
.....Spider
对于多个页面，您可以使用 Spider解决这个问题。
import aiofiles
from aspider import AttrField, TextField, Item, Spider
class HackerNewsItem(Item):
target_item = TextField(css_select='tr.athing')
title = TextField(css_select='a.storylink')
url = AttrField(css_select='a.storylink', attr='href')
async def clean_title(self, value):
return value
class HackerNewsSpider(Spider):
start_urls = ['https://news.ycombinator.com/', 'https://news.ycombinator.com/news?p=2']
async def parse(self, res):
items = await HackerNewsItem.get_items(html=res.html)
for item in items:
async with aiofiles.open('./hacker_news.txt', 'a') as f:
await f.write(item.title + '\n')
if __name__ == '__main__':
HackerNewsSpider.start()
Run hacker_news_spider.py:
[2018-07-11 17:50:12,430]-aspider-INFO Spider started!
[2018-07-11 17:50:12,430]-Request-INFO <GET: https://news.ycombinator.com/>
[2018-07-11 17:50:12,456]-Request-INFO <GET: https://news.ycombinator.com/news?p=2>
[2018-07-11 17:50:14,785]-aspider-INFO Time usage: 0:00:02.355062
[2018-07-11 17:50:14,785]-aspider-INFO Spider finished!运行hacker_news_spider.py：
[2018-07-11 17:50:12,430]-aspider-INFO Spider started!
[2018-07-11 17:50:12,430]-Request-INFO <GET: https://news.ycombinator.com/>
[2018-07-11 17:50:12,456]-Request-INFO <GET: https://news.ycombinator.com/news?p=2>
[2018-07-11 17:50:14,785]-aspider-INFO Time usage: 0:00:02.355062
[2018-07-11 17:50:14,785]-aspider-INFO Spider finished!TODO
- 自定义中间件
- JavaScript支持
- 友好的回应
贡献
- Pull Request
- Open Issue
谢谢
demiurge
https://github.com/matiasb/demiurge以上是关于基于asyncio的轻量异步微爬虫框架的主要内容，如果未能解决你的问题，请参考以下文章