当前位置 博文首页 > 基于xpath选择器、PyQuery、正则表达式的格式清理工具详解
1，使用xpath清理不必要的标签元素，以及无内容标签
from lxml import etree
def xpath_clean(self, text: str, xpath_dict: dict) -> str:
'''
xpath 清除不必要的元素
:param text: html_content
:param xpath_dict: 清除目标xpath
:return: string type html_content
'''
remove_by_xpath = xpath_dict if xpath_dict else dict()
# 必然清除的项目 除非极端情况 一般这些都是要清除的
remove_by_xpath.update({
'_remove_2': '//iframe',
'_remove_4': '//button',
'_remove_5': '//form',
'_remove_6': '//input',
'_remove_7': '//select',
'_remove_8': '//option',
'_remove_9': '//textarea',
'_remove_10': '//figure',
'_remove_11': '//figcaption',
'_remove_12': '//frame',
'_remove_13': '//video',
'_remove_14': '//script',
'_remove_15': '//style'
})
parser = etree.HTMLParser(remove_blank_text=True, remove_comments=True)
selector = etree.HTML(text, parser=parser)
# 常规删除操作，不需要的标签删除
for xpath in remove_by_xpath.values():
for bad in selector.xpath(xpath):
bad_string = etree.tostring(bad, encoding='utf-8',
pretty_print=True).decode()
logger.debug(f"clean article content : {bad_string}")
bad.getparent().remove(bad)
skip_tip = "name()='img' or name()='tr' or " \
"name()='th' or name()='tbody' or " \
"name()='thead' or name()='table'"
# 判断所有p标签，是否有内容存在，没有的直接删除
for p in selector.xpath(f"//*[not({skip_tip})]"):
# 跳过逻辑
if p.xpath(f".//*[{skip_tip}]") or \
bool(re.sub('\s', '', p.xpath('string(.)'))):
continue
bad_p = etree.tostring(p, encoding='utf-8',
pretty_print=True).decode()
logger.debug(f"clean p tag : {bad_p}")
p.getparent().remove(p)
return etree.tostring(selector, encoding='utf-8',
pretty_print=True).decode()
2，使用pyquery清理标签属性，并返回处理后源码和纯净文本
#!/usr/bin/env python
# -*-coding:utf-8-*-
from pyquery import PyQuery as pq
def pyquery_clean(self, text, url, pq_dict) -> object:
'''
pyquery 做出必要的处理，
:param text:
:param url:
:param pq_dict:
:return:
'''
# 删除pq表达式字典
remove_by_pq = pq_dict if pq_dict else dict()
# 标签属性白名单
attr_white_list = ['rowspan', 'colspan']
# 图片链接key
img_key_list = ['src', 'data-echo', 'data-src', 'data-original']
# 生成pyquery对象
dom = pq(text)
# 删除无用标签
for bad_tag in remove_by_pq.values():
for bad in dom(bad_tag):
bad_string = pq(bad).html()
logger.debug(f"clean article content : {bad_string}")
dom.remove(bad_tag)
# 标签各个属性处理
for tag in dom('*'):
for key, value in tag.attrib.items():
# 跳过逻辑，保留表格的rowspan和colspan属性
if key in attr_white_list:
continue
# 处理图片链接，不完整url，补充完整后替换
if key in img_key_list:
img_url = self.absolute_url(url, value)
pq(tag).remove_attr(key)
pq(tag).attr('src', img_url)
pq(tag).attr('alt', '')
# img标签的alt属性保留为空
elif key == 'alt':
pq(tag).attr(key, '')
# 其余所有属性做删除操作
else:
pq(tag).remove_attr(key)
return dom.text(), dom.html()
3，正则表达清理空格以及换行符内容
#!/usr/bin/env python
# -*-coding:utf-8-*-
import re
def regular_clean(self, str1: str, str2: str):
'''
正则表达式处理数据格式
:param str1: content
:param str2: html_content
:return: 返回处理后的结果
'''
def new_line(text):
text = re.sub('<br\s?/?>', '<br>', text)
text = re.sub(
'</?a>|</?em>|</?html>|</?body>|'
'</?head>|<[a-zA-Z]{1,10}\s?/>|'
'</?strong>|</?blockquote>|</?b>|'
'</?span>|</?i>|</?hr>|</?font>',
'',
text)
text = re.sub('\n', '', text)
text = re.sub('<h[1-6]>', '<p>', text)
text = re.sub('</h[1-6]>', '</p>', text)
text = text.replace('</p>', '</p>\n').replace('<br>', '<br/>')
return text
str1, str2 = self.clean_blank(str1), self.clean_blank(str2) # TODO 处理空白行问题
# TODO html_content处理 1，删除多余的无法使用的标签以及影响数据展示的标签 2，换行符问题处理以及更换
str2 = new_line(text=str2)
return str1, str2
结尾部分，各个方法封装类代码展示
#!/usr/bin/env python
# -*-coding:utf-8-*-
'''
author: szhan
date：2020-08-17
summery: 清理html_conent以及获取纯净数据格式
'''
import re
from lxml import etree
from pyquery import PyQuery as pq
from urllib.parse import urlsplit, urljoin
from loguru import logger
class CleanArticle:
def __init__(
self,
text: str,
url: str = '',
xpath_dict: dict = None,
pq_dict: dict = None
):
self.text = text
self.url = url
self.xpath_dict = xpath_dict or dict()
self.pq_dict = pq_dict or dict()
@staticmethod
def absolute_url(baseurl: str, url: str) -> str:
'''
补充url
:param baseurl:scheme url
:param url: target url
:return: complete url
'''
target_url = url if urlsplit(url).scheme else urljoin(baseurl, url)
return target_url
@staticmethod
def clean_blank(text):
'''
空白处理
:param text:
:return:
'''
text = text.replace(' ', '').replace('\u3000', '').replace('\t', '').replace('\xa0', '')
text = re.sub('\s{2,}', '', text)
text = re.sub('\n{2,}', '\n', text)
text = text.strip('\n').strip()
return text
def run(self):
'''
:return:处理后的content, html_content
'''
if (not bool(self.text)) or (not isinstance(self.text, str)):
raise ValueError('html_content has a bad type value')
# 首先，使用xpath去除空格，以及注释，iframe, button, form, script, style, video等标签
text = self.xpath_clean(self.text, self.xpath_dict)
# 第二步，使用pyquery处理具体细节方面
str1, str2 = self.pyquery_clean(text, self.url, self.pq_dict)
# 最终的正则处理
content, html_content = self.regular_clean(str1, str2)
return content, html_content
def xpath_clean(self, text: str, xpath_dict: dict) -> str:
'''
xpath 清除不必要的元素
:param text: html_content
:param xpath_dict: 清除目标xpath
:return: string type html_content
'''
remove_by_xpath = xpath_dict if xpath_dict else dict()
# 必然清除的项目 除非极端情况 一般这些都是要清除的
remove_by_xpath.update({
'_remove_2': '//iframe',
'_remove_4': '//button',
'_remove_5': '//form',
'_remove_6': '//input',
'_remove_7': '//select',
'_remove_8': '//option',
'_remove_9': '//textarea',
'_remove_10': '//figure',
'_remove_11': '//figcaption',
'_remove_12': '//frame',
'_remove_13': '//video',
'_remove_14': '//script',
'_remove_15': '//style'
})
parser = etree.HTMLParser(remove_blank_text=True, remove_comments=True)
selector = etree.HTML(text, parser=parser)
# 常规删除操作，不需要的标签删除
for xpath in remove_by_xpath.values():
for bad in selector.xpath(xpath):
bad_string = etree.tostring(bad, encoding='utf-8',
pretty_print=True).decode()
logger.debug(f"clean article content : {bad_string}")
bad.getparent().remove(bad)
skip_tip = "name()='img' or name()='tr' or " \
"name()='th' or name()='tbody' or " \
"name()='thead' or name()='table'"
# 判断所有p标签，是否有内容存在，没有的直接删除
for p in selector.xpath(f"//*[not({skip_tip})]"):
# 跳过逻辑
if p.xpath(f".//*[{skip_tip}]") or \
bool(re.sub('\s', '', p.xpath('string(.)'))):
continue
bad_p = etree.tostring(p, encoding='utf-8',
pretty_print=True).decode()
logger.debug(f"clean p tag : {bad_p}")
p.getparent().remove(p)
return etree.tostring(selector, encoding='utf-8',
pretty_print=True).decode()
def pyquery_clean(self, text, url, pq_dict) -> object:
'''
pyquery 做出必要的处理，
:param text:
:param url:
:param pq_dict:
:return:
'''
# 删除pq表达式字典
remove_by_pq = pq_dict if pq_dict else dict()
# 标签属性白名单
attr_white_list = ['rowspan', 'colspan']
# 图片链接key
img_key_list = ['src', 'data-echo', 'data-src', 'data-original']
# 生成pyquery对象
dom = pq(text)
# 删除无用标签
for bad_tag in remove_by_pq.values():
for bad in dom(bad_tag):
bad_string = pq(bad).html()
logger.debug(f"clean article content : {bad_string}")
dom.remove(bad_tag)
# 标签各个属性处理
for tag in dom('*'):
for key, value in tag.attrib.items():
# 跳过逻辑，保留表格的rowspan和colspan属性
if key in attr_white_list:
continue
# 处理图片链接，不完整url，补充完整后替换
if key in img_key_list:
img_url = self.absolute_url(url, value)
pq(tag).remove_attr(key)
pq(tag).attr('src', img_url)
pq(tag).attr('alt', '')
# img标签的alt属性保留为空
elif key == 'alt':
pq(tag).attr(key, '')
# 其余所有属性做删除操作
else:
pq(tag).remove_attr(key)
return dom.text(), dom.html()
def regular_clean(self, str1: str, str2: str):
'''
正则表达式处理数据格式
:param str1: content
:param str2: html_content
:return: 返回处理后的结果
'''
def new_line(text):
text = re.sub('<br\s?/?>', '<br>', text)
text = re.sub(
'</?a>|</?em>|</?html>|</?body>|'
'</?head>|<[a-zA-Z]{1,10}\s?/>|'
'</?strong>|</?blockquote>|</?b>|'
'</?span>|</?i>|</?hr>|</?font>',
'',
text)
text = re.sub('\n', '', text)
text = re.sub('<h[1-6]>', '<p>', text)
text = re.sub('</h[1-6]>', '</p>', text)
text = text.replace('</p>', '</p>\n').replace('<br>', '<br/>')
return text
str1, str2 = self.clean_blank(str1), self.clean_blank(str2) # TODO 处理空白行问题
# TODO html_content处理 1，删除多余的无法使用的标签以及影响数据展示的标签 2，换行符问题处理以及更换
str2 = new_line(text=str2)
return str1, str2
if __name__ == '__main__':
with open('html_content.html', 'r', encoding='utf-8') as f:
lines = f.readlines()
html = ''
for line in lines:
html += line
ca = CleanArticle(text=html)
_, html_content = ca.run()
print(html_content)
总结
jsjbwy