Node.js Web 爬蟲：Node Osmosis

Osmosis 是 Node.js 用來解析 HTML/XML 和 Web 內容爬取的擴展。

Features

• Fast: uses libxml C bindings
• Lightweight: no dependencies like jQuery, cheerio, or jsdom
• Clean: promise based interface- no more nested callbacks
• Flexible: supports both CSS and XPath selectors
• Predictable: same input, same output, same order
• Detailed logging for every step
• Precise and natural IO flow- no setTimeout or process.nextTick
• Easy debugging with built-in stack size and memory usage reporting
• Memory leak free

Example: scrape all craigslist listings

var osmosis = require('osmosis');

osmosis
.get('www.craigslist.org/about/sites') 
.find('h1 + div a')
.set('location')
.follow('@href')
.find('header + div + div li > a')
.set('category')
.follow('@href')
.find('p > a', '.totallink + a.button.next:first')
.follow('@href')
.set({
    'title':        'section > h2',
    'description':  '#postingbody',
    'subcategory':  'div.breadbox > span[4]',
    'date':         'time@datetime',
    'latitude':     '#map@data-latitude',
    'longitude':    '#map@data-longitude',
    'images[]':     'img@src'
})
.data(function(listing) {
    // do something with listing data
})

項目主頁：http://www.baiduhome.net/lib/view/home/1428322356791