在线教程爬下来转换成PDF文件

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 = """



    


{content}


"""


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 = "(

            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()