Python脚本生成sitemap

项目需要用脚本生成sitemap，中间学习了一下sitemap的格式和lxml库的用法。把结果记录一下，方便以后需要直接拿来用。
来自Python脚本生成sitemap

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安装lxml

首先需要pip install lxml安装lxml库。
如果你在ubuntu上遇到了以下错误:

#include "libxml/xmlversion.h"

compilation terminated.

error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

----------------------------------------
Cleaning up...
  Removing temporary dir /tmp/pip_build_root...
Command /usr/bin/python -c "import setuptools, tokenize;__file__='/tmp/pip_build_root/lxml/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-O4cIn6-record/install-record.txt --single-version-externally-managed --compile failed with error code 1 in /tmp/pip_build_root/lxml
Exception information:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 122, in main
    status = self.run(options, args)
  File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 283, in run
    requirement_set.install(install_options, global_options, root=options.root_path)
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 1435, in install
    requirement.install(install_options, global_options, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 706, in install
    cwd=self.source_dir, filter_stdout=self._filter_install, show_stdout=False)
  File "/usr/lib/python2.7/dist-packages/pip/util.py", line 697, in call_subprocess
    % (command_desc, proc.returncode, cwd))
InstallationError: Command /usr/bin/python -c "import setuptools, tokenize;__file__='/tmp/pip_build_root/lxml/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-O4cIn6-record/install-record.txt --single-version-externally-managed --compile failed with error code 1 in /tmp/pip_build_root/lxml

请安装以下依赖：

sudo apt-get install libxml2-dev libxslt1-dev

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Python代码

下面是生成sitemap和sitemapindex索引的代码，可以按照需求传入需要的参数，或者增加字段：

#!/usr/bin/env python
# -*- coding:utf-8 -*-

import io
import re
from lxml import etree


def generate_xml(filename, url_list):
    """Generate a new xml file use url_list"""
    root = etree.Element('urlset',
                         xmlns="http://www.sitemaps.org/schemas/sitemap/0.9")
    for each in url_list:
        url = etree.Element('url')
        loc = etree.Element('loc')
        loc.text = each
        url.append(loc)
        root.append(url)

    header = u'<?xml version="1.0" encoding="UTF-8"?>\n'
    s = etree.tostring(root, encoding='utf-8', pretty_print=True)
    with io.open(filename, 'w', encoding='utf-8') as f:
        f.write(unicode(header+s))


def update_xml(filename, url_list):
    """Add new url_list to origin xml file."""
    f = open(filename, 'r')
    lines = [i.strip() for i in f.readlines()]
    f.close()

    old_url_list = []
    for each_line in lines:
        d = re.findall('<loc>(http:\/\/.+)<\/loc>', each_line)
        old_url_list += d
    url_list += old_url_list

    generate_xml(filename, url_list)


def generatr_xml_index(filename, sitemap_list, lastmod_list):
    """Generate sitemap index xml file."""
    root = etree.Element('sitemapindex',
                         xmlns="http://www.sitemaps.org/schemas/sitemap/0.9")
    for each_sitemap, each_lastmod in zip(sitemap_list, lastmod_list):
        sitemap = etree.Element('sitemap')
        loc = etree.Element('loc')
        loc.text = each_sitemap
        lastmod = etree.Element('lastmod')
        lastmod.text = each_lastmod
        sitemap.append(loc)
        sitemap.append(lastmod)
        root.append(sitemap)

    header = u'<?xml version="1.0" encoding="UTF-8"?>\n'
    s = etree.tostring(root, encoding='utf-8', pretty_print=True)
    with io.open(filename, 'w', encoding='utf-8') as f:
        f.write(unicode(header+s))


if __name__ == '__main__':
    urls = ['http://www.baidu.com'] * 10
    mods = ['2004-10-01T18:23:17+00:00'] * 10
    generatr_xml_index('index.xml', urls, mods)

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效果

生成的效果应该是这种格式：
sitemap格式:

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>http://www.example.com/foo.html</loc>
  </url>
</urlset>

sitemapindex格式：

<?xml version="1.0" encoding="UTF-8"?>
   <sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
   <sitemap>
      <loc>http://www.example.com/sitemap1.xml.gz</loc>
      <lastmod>2004-10-01T18:23:17+00:00</lastmod>
   </sitemap>
   <sitemap>
      <loc>http://www.example.com/sitemap2.xml.gz</loc>
      <lastmod>2005-01-01</lastmod>
   </sitemap>
   </sitemapindex>

lastmod时间格式的问题

格式是用ISO 8601的标准，如果是linux/unix系统，可以使用以下函数获取

def get_lastmod_time(filename):
    time_stamp = os.path.getmtime(filename)
    t = time.localtime(time_stamp)
    return time.strftime('%Y-%m-%dT%H:%M:%S+08:00', t)

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Ref:
创建站点地图
sitemap
lxml
谷歌(Google)网站地图的XML文档格式说明
Google Sitemap文件格式