Python爬虫实战案例：爬取新闻资讯

标签：dom   ons   meta   实战案例   time   pre   字符   yield   tail   

前言

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一个简单的Python资讯采集案例，列表页到详情页，到数据保存，保存为txt文档，网站网页结构算是比较规整，简单清晰明了，资讯新闻内容的采集和保存！

 

 

应用到的库

requests，time，re，UserAgent，etree

import requests,time,re
from fake_useragent import UserAgent
from lxml import etree

列表页面

 

列表页，链接xpath解析

href_list=req.xpath(‘//ul[@class="news-list"]/li/a/@href‘)

详情页

 

 

内容xpath解析

h2=req.xpath(‘//div[@class="title-box"]/h2/text()‘)[0]
author=req.xpath(‘//div[@class="title-box"]/span[@class="news-from"]/text()‘)[0]
details=req.xpath(‘//div[@class="content-l detail"]/p/text()‘)

内容格式化处理

detail=‘\n‘.join(details)

标题格式化处理，替换非法字符

pattern = r"[\/\\\:\*\?\"\<\>\|]"
new_title = re.sub(pattern, "_", title)  # 替换为下划线

保存数据，保存为txt文本

def save(self,h2, author, detail):
    with open(f‘{h2}.txt‘,‘w‘,encoding=‘utf-8‘) as f:
        f.write(‘%s%s%s%s%s‘%(h2,‘\n‘,detail,‘\n‘,author))


    print(f"保存{h2}.txt文本成功！")

遍历数据采集，yield处理

def get_tasks(self):
    data_list = self.parse_home_list(self.url)
    for item in data_list:
        yield item

程序运行效果

 

程序采集效果

 

附源码参考：

#研招网考研资讯采集
#20200710 by微信：huguo00289
# -*- coding: UTF-8 -*-

import requests,time,re
from fake_useragent import UserAgent
from lxml import etree

class RandomHeaders(object):
    ua=UserAgent()
    @property
    def random_headers(self):
        return {
            ‘User-Agent‘: self.ua.random,
        }

class Spider(RandomHeaders):
    def __init__(self,url):
        self.url=url


    def parse_home_list(self,url):
        response=requests.get(url,headers=self.random_headers).content.decode(‘utf-8‘)
        req=etree.HTML(response)
        href_list=req.xpath(‘//ul[@class="news-list"]/li/a/@href‘)
        print(href_list)
        for href in href_list:
            item = self.parse_detail(f‘https://yz.chsi.com.cn{href}‘)
            yield item


    def parse_detail(self,url):
        print(f">>正在爬取{url}")
        try:
            response = requests.get(url, headers=self.random_headers).content.decode(‘utf-8‘)
            time.sleep(2)
        except Exception as e:
            print(e.args)
            self.parse_detail(url)
        else:
            req = etree.HTML(response)
            try:
                h2=req.xpath(‘//div[@class="title-box"]/h2/text()‘)[0]
                h2=self.validate_title(h2)
                author=req.xpath(‘//div[@class="title-box"]/span[@class="news-from"]/text()‘)[0]
                details=req.xpath(‘//div[@class="content-l detail"]/p/text()‘)
                detail=‘\n‘.join(details)
                print(h2, author, detail)
                self.save(h2, author, detail)
                return h2, author, detail
            except IndexError:
                print(">>>采集出错需延时，5s后重试..")
                time.sleep(5)
                self.parse_detail(url)


    @staticmethod
    def validate_title(title):
        pattern = r"[\/\\\:\*\?\"\<\>\|]"
        new_title = re.sub(pattern, "_", title)  # 替换为下划线
        return new_title



    def save(self,h2, author, detail):
        with open(f‘{h2}.txt‘,‘w‘,encoding=‘utf-8‘) as f:
            f.write(‘%s%s%s%s%s‘%(h2,‘\n‘,detail,‘\n‘,author))

        print(f"保存{h2}.txt文本成功！")


    def get_tasks(self):
        data_list = self.parse_home_list(self.url)
        for item in data_list:
            yield item




if __name__=="__main__":
    url="https://yz.chsi.com.cn/kyzx/jyxd/"
    spider=Spider(url)
    for data in spider.get_tasks():
        print(data)

Python爬虫实战案例：爬取新闻资讯

标签：dom   ons   meta   实战案例   time   pre   字符   yield   tail   

原文地址：https://www.cnblogs.com/zwhy8/p/13285708.html