您的位置：首页 > 编程语言 > Python开发

在线教程爬下来转换成PDF文件

2017-03-26 17:00 239 查看
廖雪峰Python教程

# coding=utf-8
import logging
import os
import re
import time

try:
from urllib.parse import urlparse  # py3
except:
from urlparse import urlparse  # py2

import pdfkit
import requests
from bs4 import BeautifulSoup

html_template = """
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
</head>
<body>
{content}
</body>
</html>
"""

class Crawler(object):
"""
爬虫基类，所有爬虫都应该继承此类
"""
name = None

def __init__(self, name, start_url):
"""
初始化
:param name: 保存问的PDF文件名,不需要后缀名
:param start_url: 爬虫入口URL
"""
self.name = name
self.start_url = start_url
self.domain = '{uri.scheme}://{uri.netloc}'.format(uri=urlparse(self.start_url))

def crawl(self, url):
"""
pass
:return:
"""
print(url)
response = requests.get(url)
return response

def parse_menu(self, response):
"""
解析目录结构,获取所有URL目录列表:由子类实现
:param response 爬虫返回的response对象
:return: url 可迭代对象(iterable) 列表,生成器,元组都可以
"""
raise NotImplementedError

def parse_body(self, response):
"""
解析正文,由子类实现
:param response: 爬虫返回的response对象
:return: 返回经过处理的html文本
"""
raise NotImplementedError

def run(self):
start = time.time()
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,
}
htmls = []
for index, url in enumerate(self.parse_menu(self.crawl(self.start_url))):
html = self.parse_body(self.crawl(url))
f_name = ".".join([str(index), "html"])
with open(f_name, 'wb') as f:
f.write(html)
htmls.append(f_name)

pdfkit.from_file(htmls, self.name + ".pdf", options=options)
for html in htmls:
os.remove(html)
total_time = time.time() - start
print(u"总共耗时：%f 秒" % total_time)

class LiaoxuefengPythonCrawler(Crawler):
"""
廖雪峰Python3教程
"""

def parse_menu(self, response):
"""
解析目录结构,获取所有URL目录列表
:param response 爬虫返回的response对象
:return: url生成器
"""
soup = BeautifulSoup(response.content, "html.parser")
menu_tag = soup.find_all(class_="uk-nav uk-nav-side")[1]
for li in menu_tag.find_all("li"):
url = li.a.get("href")
if not url.startswith("http"):
url = "".join([self.domain, url])  # 补全为全路径
yield url

def parse_body(self, response):
"""
解析正文
:param response: 爬虫返回的response对象
:return: 返回处理后的html文本
"""
try:
soup = BeautifulSoup(response.content, 'html.parser')
body = soup.find_all(class_="x-wiki-content")[0]

# 加入标题, 居中显示
title = soup.find('h4').get_text()
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 = "".join([m.group(1), self.domain, m.group(2), m.group(3)])
return rtn
else:
return "".join([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")
return html
except Exception as e:
logging.error("解析错误", exc_info=True)

if __name__ == '__main__':
start_url = "http://www.liaoxuefeng.com/wiki/0014316089557264a6b348958f449949df42a6d3a2e542c000"
crawler = LiaoxuefengPythonCrawler("廖雪峰Git", start_url)
crawler.run()
内容来自用户分享和网络整理，不保证内容的准确性，如有侵权内容，可联系管理员处理 点击这里给我发消息
标签：  python
相关文章推荐
新的分享
章节导航