从廖雪峰老师的python教程入门的，最近在看python爬虫，入手了一下
代码比较low，没有用到多线程和ip代理池
然后呢，由于robots.txt的限定，构建了一些user-agent，并放慢的爬虫的速度,起到一些效果,可能多次抓取才能完成所有文章~~~
仅供一些刚入门的同学参考一下........
用到的库及工具:(自行百度)
1.BeautifulSoup4
2.pdfkit
3.requests
4.wkhtmltopdf(需添加环境变量)
代码如下：
# -*- coding:utf-8 -*-
# @author:lijinxi
# @file: __init__.py.py
# @time: 2018/05/07
import requests
from bs4 import BeautifulSoup
import pdfkit
import time
import os
import re
import random
class Crawel(object):
def __init__(self):
self.htmlTemplate = '''
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
</head>
<body>
{content}
</body>
</html>
'''
# robots.txt不允许,设置请求头
user_agent=[
"Mozilla / 5.0(Windows NT 10.0;Win64; x64) AppleWebKit / 537.36(KHTML, likeGecko) Chrome / 66.0.3359.139,Safari / 537.36",
"Mozilla / 5.0(Windows NT 10.0;Win64; x64) AppleWebKit / 537.36(KHTML, likeGecko) Chrome / 58.0.3029.110Safari / 537.36 Edge / 16.16299",
" Mozilla / 5.0(WindowsNT10.0;WOW64;Trident / 7.0;LCTE;rv: 11.0) likeGecko",
"Mozilla / 5.0(Windows NT 10.0;Win64;x64;rv: 59.0) Gecko / 20100101Firefox / 59.0",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.11 TaoBrowser/2.0 Safari/536.11",
"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.71 Safari/537.1 LBBROWSER",
"Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; QQBrowser/7.0.3698.400)",
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; QQDownload 732; .NET4.0C; .NET4.0E)",
"Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0)"
]
self.headers = {
"Proxy-Connection": "keep-alive",
"Pragma": "no-cache",
"Cache-Control": "no-cache",
"User - Agent": (user_agent[random.randint(0,len(user_agent)-1)]),
"Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
",
"Accept-Encoding": "gzip, deflate, sdch",
"Accept-Language": "zh-CN,zh;q=0.8,en-US;q=0.6,en;q=0.4",
"Accept-Charset": "gb2312,gbk;q=0.7,utf-8;q=0.7,*;q=0.7",
"Referer": "https: // www.liaoxuefeng.com /",
}
def getPageLinks(self):
'''
获取所有的URL集合
:return:
'''
response = requests.get("https://www.liaoxuefeng.com/wiki/0014316089557264a6b348958f449949df42a6d3a2e542c000",
headers=self.headers)
bsObj = BeautifulSoup(response.text, "lxml")
menu_list = bsObj.find("ul", {"id": "x-wiki-index", "class": "uk-nav uk-nav-side"})
pageLinks = []
for pageLink in menu_list.findAll("a", {"class": "x-wiki-index-item"}):
if pageLink.attrs["href"] is not None:
newLink = "https://www.liaoxuefeng.com" + pageLink.attrs["href"]
pageLinks.append(newLink)
return pageLinks
def getUrlContent(self, url, file):
'''
解析URL,获取HTML内容
:param url:
:param file:保存的html 文件名
:return:
'''
response = requests.get(url, headers=self.headers)
bsObj = BeautifulSoup(response.text, "lxml")
# 正文
pageContent = bsObj.find("div", {"class": "x-wiki-content x-main-content"})
# 标题
pageTitle = bsObj.find("h4").get_text()
# 标题放在正文之前居中显示
center_tag = bsObj.new_tag("center")
title_tag = bsObj.new_tag("h1")
title_tag.string = pageTitle
center_tag.insert(1, title_tag)
pageContent.insert(0, center_tag)
html = str(pageContent)
html = self.htmlTemplate.format(content=html)
html = html.encode("utf-8")
with open(file, 'wb+') as f:
f.write(html)
return file
def sloveImage(self, filename1, filename2):
'''
解决图片不能正常保存的问题
由路径引起,尝试修改路径
:param filename1:原始文件
:param filename2:修改后要保存的文件
:return:
'''
with open(filename1, "rb+") as f:
text = f.read().decode("utf-8")
text = text.replace("data-src", "src")
with open(filename2, "wb+") as f:
f.write(text.encode("utf-8"))
return filename2
def savePdf(self, htmls, filename):
'''
将所有的html保存到pdf文件
:param htmls:
:param filename:
: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, filename, options=options)
def main():
'''
处理
:return:
'''
start = time.time()
crawer = Crawel()
filename = "liaoxuefeng_blogs_python3.pdf"
pageLinks = crawer.getPageLinks()
htmls = [] # html文件列表
for index, pageLink in enumerate(pageLinks):
if index<18:
continue
filename1 = "index" + str(index) + ".html"
filename2 = "indexc" + str(index) + ".html"
crawer.getUrlContent(pageLink, filename1)
waittime=random.randint(0,20)+20;
time.sleep(waittime) # 给自己留一线生机
html = crawer.sloveImage(filename1, filename2)
htmls.append(html)
print("第%d页采集完成........." % index)
crawer.savePdf(htmls, filename)
# 移除html文件
''''
rex = re.compile("^index.*\.html$")
for i in os.listdir():
if rex.match(i):
os.remove(i)
'''
total_time = time.time() - start
print("总共运行了%d秒" % total_time)
if __name__ == '__main__':
main()进一步完善中..........................^<>^