我正在尝试获取大量的状态信息，这些信息在网站中进行编码，主要在＆＃34;＆lt; head＆gt;＆lt; / head＆gt;＆＃34;元件。
我知道我可以使用wget或curl或python来获取整个页面。但我不想给服务器施加太多不必要的压力（页面本身相当大/复杂）。
是否有任何方法只获取头元素？
我认为除了检查html标题之外，还有一些代理服务器。
Jusk澄清：我不会搜索html-headers，仅用于html - <head>。
答案 0 :(得分：1)
无法仅加载<head>标记之间的数据，因为服务器必须在发送之前解析所请求的页面。
可能的解决方案是读取几个字节，直到找到</head>标记。
以下内容从源读取n个字节，并检查是否包含字符串</head>。如果是，则将字节转换为string并进行修剪，使得结果包含标记<head>和</head>以及它们之间的数据。否则，它将继续读取n个字节，直到找到</head>。
import urllib.request
def get_head_tag_data(url, n=512):
"""Read n bytes form source until '</head> is included. Trim result to
'<head> ... </head>' and return it as string."""
# open resource
with urllib.request.urlopen(url) as site:
# read n bytes until `buff` includes "</head>"
data = b''
i = 1
while True:
buff = site.read(n)
data += buff
if b'</head>' in buff:
break
elif buff == b'':
raise AttributeError('Not head-tag found.')
i += 1
print('{} bytes read'.format(n*i))
# cast to string
data = str(data)
# detect tag position
start_tag = data.find('<head>')
end_tag = data.find('</head>') + 7
return data[start_tag:end_tag]
tag_data = get_head_tag_data('https://stackoverflow.com', n=256)
请注意，此函数不会检查可能的错误，例如，如果没有</head>标记。
答案 1 :(得分：-2)
你可以尝试BeautifulSoap。这是一个示例 Python 脚本。
import urllib.request as urllib2
from bs4 import BeautifulSoup as bs
url = 'change_wiht_your_desired_url' # www.https://stackoverflow.com/questions/48262523/get-only-html-head-element-with-a-script-or-tool
page = urllib2.urlopen(url)
soup = bs(page, 'html.parser')
soup.head
您可以使用soup对象获取不同的标记。阅读完整的docs here。我希望这会有所帮助。
修改
print(soup.head)输出
<head>
<title>Memory Leak with import_array() for numpy Python3.5 - Stack Overflow</title>
<link href="https://cdn.sstatic.net/Sites/stackoverflow/img/favicon.ico?v=4f32ecc8f43d" rel="shortcut icon"/>
<link href="https://cdn.sstatic.net/Sites/stackoverflow/img/apple-touch-icon.png?v=c78bd457575a" rel="apple-touch-icon image_src"/>
<link href="/opensearch.xml" rel="search" title="Stack Overflow" type="application/opensearchdescription+xml"/>
<meta content="website" property="og:type"/>
<meta content="https://stackoverflow.com/questions/48200892/memory-leak-with-import-array-for-numpy-python3-5" property="og:url"/>
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<meta content="summary" name="twitter:card"/>
<meta content="stackoverflow.com" name="twitter:domain"/>
<meta content="Memory Leak with import_array() for numpy Python3.5" itemprop="title name" name="twitter:title" property="og:title"/>
<meta content="Could someone suggest a fix for this problem?
When I use import_array(), Valgrind reports memory leak of 157528 bytes.
Here is the small piece of code to replicate the problem on Ubuntu16.04 and P..." itemprop="description" name="twitter:description" property="og:description"/>
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