在做网站项目时，经常会使用脚本生成sitemap， 便于爬虫爬取，有利于SEO。 那么如何使用Python来生成sitemap呢？下面我们来研究一番。
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
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)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) return time.strftime('%Y-%m-%dT%H:%M:%SZ', t)
优化
一般来说，用lxml效率低并且内存占用比较大，可以直接用文件的write方法创建。
def generate_xml(filename, url_list):
with gzip.open(filename,"w") as f:
f.write("""<?xml version="1.0" encoding="utf-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">\n""")
for i in url_list:
f.write("""<url><loc>%s</loc></url>\n"""%i)
f.write("""</urlset>""")
def append_xml(filename, url_list):
with gzip.open(filename, 'r') as f:
for each_line in f:
d = re.findall('<loc>(http:\/\/.+)<\/loc>', each_line)
url_list.extend(d)
generate_xml(filename, set(url_list))
def modify_time(filename):
time_stamp = os.path.getmtime(filename)
t = time.localtime(time_stamp)
return time.strftime('%Y-%m-%dT%H:%M:%S:%SZ', t)
def new_xml(filename, url_list):
generate_xml(filename, url_list)
root = dirname(filename)
with open(join(dirname(root), "sitemap.xml"),"w") as f:
f.write('<?xml version="1.0" encoding="utf-8"?>\n<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">\n')
for i in glob.glob(join(root,"*.xml.gz")):
lastmod = modify_time(i)
i = i[len(CONFIG.SITEMAP_PATH):]
f.write("<sitemap>\n<loc>http:/%s</loc>\n"%i)
f.write("<lastmod>%s</lastmod>\n</sitemap>\n"%lastmod)
f.write('</sitemapindex>')以上是使用Python生成sitemap的详细介绍的详细内容。更多信息请关注PHP中文网其他相关文章！
