Python实现抓取HTML网页并以PDF文件形式保存的方法
作者:Limerence 时间:2022-12-15 22:56:30
本文实例讲述了Python实现抓取HTML网页并以PDF文件形式保存的方法。分享给大家供大家参考,具体如下:
一、前言
今天介绍将HTML网页抓取下来,然后以PDF保存,废话不多说直接进入教程。
今天的例子以廖雪峰老师的Python教程网站为例:http://www.liaoxuefeng.com/wiki/0014316089557264a6b348958f449949df42a6d3a2e542c000
二、准备工作
1. PyPDF2的安装使用(用来合并PDF):
PyPDF2版本:1.25.1
https://pypi.python.org/pypi/PyPDF2/1.25.1
或
https://github.com/mstamy2/PyPDF2
安装:
pip install PyPDF2
使用示例:
from PyPDF2 import PdfFileMerger
merger = PdfFileMerger()
input1 = open("hql_1_20.pdf", "rb")
input2 = open("hql_21_40.pdf", "rb")
merger.append(input1)
merger.append(input2)
# Write to an output PDF document
output = open("hql_all.pdf", "wb")
merger.write(output)
2. requests、beautifulsoup 是爬虫两大神器,reuqests 用于网络请求,beautifusoup 用于操作 html 数据。有了这两把梭子,干起活来利索。scrapy 这样的爬虫框架我们就不用了,这样的小程序派上它有点杀鸡用牛刀的意思。此外,既然是把 html 文件转为 pdf,那么也要有相应的库支持, wkhtmltopdf 就是一个非常的工具,它可以用适用于多平台的 html 到 pdf 的转换,pdfkit 是 wkhtmltopdf 的Python封装包。首先安装好下面的依赖包
pip install requests
pip install beautifulsoup4
pip install pdfkit
3. 安装 wkhtmltopdf
Windows平台直接在 http://wkhtmltopdf.org/downloads.html 下载稳定版的 wkhtmltopdf 进行安装,安装完成之后把该程序的执行路径加入到系统环境 $PATH 变量中,否则 pdfkit 找不到 wkhtmltopdf 就出现错误 “No wkhtmltopdf executable found”。Ubuntu 和 CentOS 可以直接用命令行进行安装
$ sudo apt-get install wkhtmltopdf # ubuntu
$ sudo yum intsall wkhtmltopdf # centos
三、数据准备
1. 获取每篇文章的url
def get_url_list():
"""
获取所有URL目录列表
:return:
"""
response = requests.get("http://www.liaoxuefeng.com/wiki/0014316089557264a6b348958f449949df42a6d3a2e542c000")
soup = BeautifulSoup(response.content, "html.parser")
menu_tag = soup.find_all(class_="uk-nav uk-nav-side")[1]
urls = []
for li in menu_tag.find_all("li"):
url = "http://www.liaoxuefeng.com" + li.a.get('href')
urls.append(url)
return urls
2. 通过文章url用模板保存每篇文章的HTML文件
html模板:
html_template = """
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
</head>
<body>
{content}
</body>
</html>
"""
进行保存:
def parse_url_to_html(url, name):
"""
解析URL,返回HTML内容
:param url:解析的url
:param name: 保存的html文件名
:return: html
"""
try:
response = requests.get(url)
soup = BeautifulSoup(response.content, 'html.parser')
# 正文
body = soup.find_all(class_="x-wiki-content")[0]
# 标题
title = soup.find('h4').get_text()
# 标题加入到正文的最前面,居中显示
center_tag = soup.new_tag("center")
title_tag = soup.new_tag('h1')
title_tag.string = title
center_tag.insert(1, title_tag)
body.insert(1, center_tag)
html = str(body)
# body中的img标签的src相对路径的改成绝对路径
pattern = "(<img .*?src=\")(.*?)(\")"
def func(m):
if not m.group(3).startswith("http"):
rtn = m.group(1) + "http://www.liaoxuefeng.com" + m.group(2) + m.group(3)
return rtn
else:
return m.group(1)+m.group(2)+m.group(3)
html = re.compile(pattern).sub(func, html)
html = html_template.format(content=html)
html = html.encode("utf-8")
with open(name, 'wb') as f:
f.write(html)
return name
except Exception as e:
logging.error("解析错误", exc_info=True)
3. 把html转换成pdf
def save_pdf(htmls, file_name):
"""
把所有html文件保存到pdf文件
:param htmls: html文件列表
:param file_name: pdf文件名
:return:
"""
options = {
'page-size': 'Letter',
'margin-top': '0.75in',
'margin-right': '0.75in',
'margin-bottom': '0.75in',
'margin-left': '0.75in',
'encoding': "UTF-8",
'custom-header': [
('Accept-Encoding', 'gzip')
],
'cookie': [
('cookie-name1', 'cookie-value1'),
('cookie-name2', 'cookie-value2'),
],
'outline-depth': 10,
}
pdfkit.from_file(htmls, file_name, options=options)
4. 把转换好的单个PDF合并为一个PDF
merger = PdfFileMerger()
for pdf in pdfs:
merger.append(open(pdf,'rb'))
print u"合并完成第"+str(i)+'个pdf'+pdf
完整源码:
# coding=utf-8
import os
import re
import time
import logging
import pdfkit
import requests
from bs4 import BeautifulSoup
from PyPDF2 import PdfFileMerger
html_template = """
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
</head>
<body>
{content}
</body>
</html>
"""
def parse_url_to_html(url, name):
"""
解析URL,返回HTML内容
:param url:解析的url
:param name: 保存的html文件名
:return: html
"""
try:
response = requests.get(url)
soup = BeautifulSoup(response.content, 'html.parser')
# 正文
body = soup.find_all(class_="x-wiki-content")[0]
# 标题
title = soup.find('h4').get_text()
# 标题加入到正文的最前面,居中显示
center_tag = soup.new_tag("center")
title_tag = soup.new_tag('h1')
title_tag.string = title
center_tag.insert(1, title_tag)
body.insert(1, center_tag)
html = str(body)
# body中的img标签的src相对路径的改成绝对路径
pattern = "(<img .*?src=\")(.*?)(\")"
def func(m):
if not m.group(3).startswith("http"):
rtn = m.group(1) + "http://www.liaoxuefeng.com" + m.group(2) + m.group(3)
return rtn
else:
return m.group(1)+m.group(2)+m.group(3)
html = re.compile(pattern).sub(func, html)
html = html_template.format(content=html)
html = html.encode("utf-8")
with open(name, 'wb') as f:
f.write(html)
return name
except Exception as e:
logging.error("解析错误", exc_info=True)
def get_url_list():
"""
获取所有URL目录列表
:return:
"""
response = requests.get("http://www.liaoxuefeng.com/wiki/0014316089557264a6b348958f449949df42a6d3a2e542c000")
soup = BeautifulSoup(response.content, "html.parser")
menu_tag = soup.find_all(class_="uk-nav uk-nav-side")[1]
urls = []
for li in menu_tag.find_all("li"):
url = "http://www.liaoxuefeng.com" + li.a.get('href')
urls.append(url)
return urls
def save_pdf(htmls, file_name):
"""
把所有html文件保存到pdf文件
:param htmls: html文件列表
:param file_name: pdf文件名
:return:
"""
options = {
'page-size': 'Letter',
'margin-top': '0.75in',
'margin-right': '0.75in',
'margin-bottom': '0.75in',
'margin-left': '0.75in',
'encoding': "UTF-8",
'custom-header': [
('Accept-Encoding', 'gzip')
],
'cookie': [
('cookie-name1', 'cookie-value1'),
('cookie-name2', 'cookie-value2'),
],
'outline-depth': 10,
}
pdfkit.from_file(htmls, file_name, options=options)
def main():
start = time.time()
file_name = u"liaoxuefeng_Python3_tutorial"
urls = get_url_list()
for index, url in enumerate(urls):
parse_url_to_html(url, str(index) + ".html")
htmls =[]
pdfs =[]
for i in range(0,124):
htmls.append(str(i)+'.html')
pdfs.append(file_name+str(i)+'.pdf')
save_pdf(str(i)+'.html', file_name+str(i)+'.pdf')
print u"转换完成第"+str(i)+'个html'
merger = PdfFileMerger()
for pdf in pdfs:
merger.append(open(pdf,'rb'))
print u"合并完成第"+str(i)+'个pdf'+pdf
output = open(u"廖雪峰Python_all.pdf", "wb")
merger.write(output)
print u"输出PDF成功!"
for html in htmls:
os.remove(html)
print u"删除临时文件"+html
for pdf in pdfs:
os.remove(pdf)
print u"删除临时文件"+pdf
total_time = time.time() - start
print(u"总共耗时:%f 秒" % total_time)
if __name__ == '__main__':
main()
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来源:https://blog.csdn.net/hubaoquanu/article/details/66973149