Get

    urllib的 request 模块可以非常方便地抓取URL内容，也就是发送一个GET请求到指定的页面，然后返回HTTP的响应：

    例如，对豆瓣的一个URL https://api.douban.com/v2/book/2129650 进行抓取，并返回响应：

    from urllib import request



    with request.urlopen('https://api.douban.com/v2/book/2129650') as f:

    data = f.read()

    print('Status:', f.status, f.reason)

    for k, v in f.getheaders():

    print('%s: %s' % (k, v))

    print('Data:', data.decode('utf-8'))

    可以看到HTTP响应的头和JSON数据：

    Status: 200 OK

    Server: nginx

    Date: Tue, 26 May 2015 10:02:27 GMT

    Content-Type: application/json; charset=utf-8

    Content-Length: 2049

    Connection: close

    Expires: Sun, 1 Jan 2006 01:00:00 GMT

    Pragma: no-cache

    Cache-Control: must-revalidate, no-cache, private

    X-DAE-Node: pidl1

    Data: {"rating":{"max":10,"numRaters":16,"average":"7.4","min":0},"subtitle":"","author":["廖雪峰编著"],"pubdate":"2007-6","tags":[{"count":20,"name":"spring","title":"spring"}…}

    如果我们要想模拟浏览器发送GET请求，就需要使用 Request 对象，通过往 Request 对象添加HTTP头，我们就可以把请求伪装成浏览器。例如，模拟iPhone 6去请求豆瓣首页：

    from urllib import request



    req = request.Request('http://www.douban.com/')

    req.add_header('User-Agent', 'Mozilla/6.0 (iPhone; CPU iPhone OS 8_0 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/8.0 Mobile/10A5376e Safari/8536.25')

    with request.urlopen(req) as f:

    print('Status:', f.status, f.reason)

    for k, v in f.getheaders():

    print('%s: %s' % (k, v))

    print('Data:', f.read().decode('utf-8'))

    这样豆瓣会返回适合iPhone的移动版网页：

    …

    <meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0">

    <meta name="format-detection" content="telephone=no">

    <link rel="apple-touch-icon" sizes="57x57" href="http://img4.douban.com/pics/cardkit/launcher/57.png&#34; />

    …