使用BeautifulSoup和pdfkit爬取菜鸟教程到pdf文件!

锋利的BeautifulSoup:

BeautifulSoup是Python爬虫里面使用较为广泛的库,其主要功能是从网页中抓取数据,可以使用较少的代码实现完整的数据爬取工作。

BeautifulSoup简介

  BeautifulSoup提供一些简单的、python式的函数用来处理导航、搜索、修改分析树等功能。它是一个工具箱,通过解析文档为用户提供需要抓取的数据,因为简单,所以不需要多少代码就可以写出一个完整的应用程序。

pdfkit简介

  pdfkit是一个把HTML+CSS格式的文件转换成PDF格式文档的一种工具。它是对html转pdf工具包wkhtmltopdf的封装,所以必须要安装wkhtmltopdf,并将wkhtmltopdf的安装路径配置到系统环境PATH中。

可以参考:pdfkit与wkhtmltopdf的安装与使用

爬取的关键代码

  列举了一些共有变量和设置的变量

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# 比如爬取python3,网址:http://www.runoob.com/python3/python3-tutorial.html
# 对该url进行拆分,对以下四个参数进行配置,一般只修改language
language = 'python3'
list_tag = '_top'
content_tag = 'content'
path_wkthmltopdf = r'C:\Program Files\wkhtmltopdf\bin\wkhtmltopdf.exe'
# 以下参数不用配置
child_url = '/' + language
url_tag = child_url + '/'
output_name = u"runoob_" + language + r"教程.pdf"

  get_url_title_list方法:获取python的章节url

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def get_url_title_list():
"""
获取所有URL和Title目录列表
:return:
"""
root = root_url
temp_child_url = child_url
resp = requests.get(root + temp_child_url)
resp.encoding = 'utf-8'
soup = BeautifulSoup(resp.text, "html.parser")
x = soup.find("div", class_="design")
x = x.find_all("a", target=list_tag)
title = []
url_path = []
for i in x:
value = i.string.strip()
title.append(value)
temp_href = i.get('href').strip()
if temp_href.find(url_tag) >= 0:
href = root + temp_href
else:
href = root + temp_child_url + '/' + temp_href
url_path.append(href)
return title, url_path

  parse_url_to_html方法:将爬取的目标网页存储为html文件

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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(id=content_tag)
# 标题
title = body.find('h1')
if title is None:
title = body.find_all('h2')[0]
title_tag = soup.new_tag('h1')
title_tag.string = title.string
title = title_tag
# 标题加入到正文的最前面,居中显示
center_tag = soup.new_tag("center")
center_tag.insert(1, title)
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"):
if m.group(2).find('https') >= 0:
return m.group(1) + m.group(2) + m.group(3)
if m.group(2).find('runoob.com') >= 0:
rtn = m.group(1) + "http:" + m.group(2) + m.group(3)
print(rtn)
else:
rtn = m.group(1) + root_url + m.group(2) + m.group(3)
print(rtn)
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)
parse_url_to_html

  save_pdf方法:将html文件转为pdf文件

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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:
"""
config = pdfkit.configuration(wkhtmltopdf=path_wkthmltopdf)
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, configuration=config)

save_pdf

  append_pdf方法:拼接pdf

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def append_pdf(input1, output1, bookmark):
bookmark_num = output1.getNumPages()
print(bookmark_num)
for page_num in range(input1.numPages):
output1.addPage(input1.getPage(page_num))

output1.addBookmark(bookmark, bookmark_num)

  在上述方法执行完成后,执行以下代码,将拼接的pdf输出到本地

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output.write(open(output_name, "wb"))

append_pdf

完整代码

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# -*-coding:utf-8-*-
import os
import re
import time
import sys
import logging
import pdfkit
import requests
from bs4 import BeautifulSoup
from PyPDF2 import PdfFileWriter, PdfFileReader
html_template = """
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
</head>
<body>
{content}
</body>
</html>
"""
root_url = "http://www.runoob.com"
# 针对Runoob.com的爬虫示例
# 列入要对该网站的python3进行爬虫,点开 python3,网址默认为:http://www.runoob.com/python3/python3-tutorial.html
# 对该url进行拆分,对以下四个参数进行配置,一般只修改language
language = 'python3' # 要爬虫的分类------针对不同的内容进行修改
list_tag = '_top' # 对左侧列表的class检索------一般不需要修改
content_tag = 'content' # 对正文的id检索------一般不需要修改
path_wkthmltopdf = r'C:\\Program Files\\wkhtmltopdf\\bin\\wkhtmltopdf.exe' # 本地 wkhtmltopdf 的配置------根据自己电脑情况配置
# 以下参数不用配置
child_url = '/' + language # 定义子url
url_tag = child_url + '/' # url_tag是对左侧列表中的url出现特殊情况下的判断
output_name = u"runoob_" + language + r"教程.pdf" # 爬虫的文件名
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(id=content_tag)
# 标题
title = body.find('h1')
if title is None:
title = body.find_all('h2')[0]
title_tag = soup.new_tag('h1')
title_tag.string = title.string
title = title_tag
# 标题加入到正文的最前面,居中显示
center_tag = soup.new_tag("center")
center_tag.insert(1, title)
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"):
if m.group(2).find('https') >= 0:
return m.group(1) + m.group(2) + m.group(3)
if m.group(2).find('runoob.com') >= 0:
rtn = m.group(1) + "http:" + m.group(2) + m.group(3)
print(rtn)
else:
rtn = m.group(1) + root_url + m.group(2) + m.group(3)
print(rtn)
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)
# 要去除所有的div标签
# 移除div(如果要移除a标签,把div换成a即可)
# remove_tag(html, "div")
def remove_tag(text, tag):
return text[:text.find("<" + tag + ">")] + text[text.find("</" + tag + ">") + len(tag) + 3:]
def get_url_title_list():
"""
获取所有URL和Title目录列表
:return:
"""
root = root_url
temp_child_url = child_url
resp = requests.get(root + temp_child_url)
resp.encoding = 'utf-8'
soup = BeautifulSoup(resp.text, "html.parser")
x = soup.find("div", class_="design")
x = x.find_all("a", target=list_tag)
title = []
url_path = []
for i in x:
value = i.string.strip()
title.append(value)
temp_href = i.get('href').strip()
if temp_href.find(url_tag) >= 0:
href = root + temp_href
else:
href = root + temp_child_url + '/' + temp_href
url_path.append(href)
return title, url_path
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:
"""
config = pdfkit.configuration(wkhtmltopdf=path_wkthmltopdf)
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, configuration=config)
def append_pdf(input1, output1, bookmark):
bookmark_num = output1.getNumPages()
print(bookmark_num)
for page_num in range(input1.numPages):
output1.addPage(input1.getPage(page_num))
output1.addBookmark(bookmark, bookmark_num)
def main():
output = PdfFileWriter()
start = time.time()
file_name = u"temp_"
result = get_url_title_list()
titles = result[0]
urls = result[1]
print(titles)
print(urls)
for index, url in enumerate(urls):
parse_url_to_html(url, str(index) + ".html")
htmls = []
pdfs = []
for i in range(0, len(urls)):
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')
i = 0
for pdf in pdfs:
fd = open(pdf, 'rb')
append_pdf(PdfFileReader(fd), output, titles[i])
i = i + 1
print(u"合并完成第" + str(i) + '个pdf' + pdf)
output.write(open(output_name, "wb"))
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__':
try:
main()
except OSError as err:
print("OS error: {0}".format(err))
except ValueError:
print("Could not convert data to an integer.")
finally:
print("Unexpected error:", sys.exc_info()[0])

存在的问题

  在删除中间生成的pdf时,报了一个错误(OS error: [WinError 32]另一个程序正在使用此文件,进程无法访问。:'temp_0.pdf'),提示文件正在使用中,删除pdf文件失败。由于正在学习python,在多次尝试解决该问题,都以失败告终,等技能提升之后再进行修复~
如果有不明白的,欢迎留言或者给我 发邮件[Send Email]


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文章目录
  1. 1. BeautifulSoup简介
  2. 2. pdfkit简介
  3. 3. 爬取的关键代码
  4. 4. 完整代码
  5. 5. 存在的问题