爬取全部的校园新闻

本次作业来源于：https://edu.cnblogs.com/campus/gzcc/GZCC-16SE1/homework/3002

读入包：　

import re
import requests
from bs4 import BeautifulSoup
from datetime import datetime
import time
import random
import pandas as pd      

0.从新闻url获取点击次数，并整理成函数

• newsUrl
• newsId(re.search())
• clickUrl(str.format())
• requests.get(clickUrl)
• re.search()/.split()
• str.lstrip(),str.rstrip()
• int
• 整理成函数
• 获取新闻发布时间及类型转换也整理成函数

　　　获取点击次数函数：

　　

def clickCounts(url):
    id = re.findall('\d+',url)[-1]
    clickUrl = "http://oa.gzcc.cn/api.php?op=count&id={}&modelid=80".format(id)
    clickStruct = requests.get(clickUrl).text
    clickCounts = int(clickStruct.split('.html')[-1][2:-3])
    return clickCounts      

1.从新闻url获取新闻详情： 字典,anews

获取发布时间：

def newsdt(showInfo):
    newsDate = showInfo.split()[0].split(':')[1]
    newsTime = showInfo.split()[1]
    newsDT = newsDate + ' ' + newsTime
    dt = datetime.strptime(newsDT,'%Y-%m-%d %H:%M:%S')
    return dt      

获取新闻详情：

def anews(url):
    newsDetail = {}
    res = requests.get(url)
    res.encoding = 'utf-8'
    soup = BeautifulSoup(res.text,'html.parser')
    newsDetail['newsTitle'] = soup.select('.show-title')[0].text
    showInfo = soup.select('.show-info')[0].text
    newsDetail['newsDT'] = newsdt(showInfo)
    newsDetail['newsClick'] = clickCounts(url)
    return newsDetail

newsUrl = "http://news.gzcc.cn/html/2019/xiaoyuanxinwen_0404/11155.html"
print(anews(newsUrl))      

2.从列表页的url获取新闻url：列表append(字典) alist

def alist(listUrl):
    res = requests.get(listUrl)
    res.encoding = 'utf-8'
    soup = BeautifulSoup(res.text,'html.parser')
    newsList = []
    for news in soup.select('li'):
        if len(news.select('.news-list-title'))>0:
            newsUrl = news.select('a')[0]['href']
            newsDesc = news.select('.news-list-description')[0].text
            newsDict = anews(newsUrl)
            newsDict['newsUrl'] = newsUrl
            newsDict['description'] = newsDesc
            newsList.append(newsDict)
    return newsList


listUrl = 'http://news.gzcc.cn/html/xiaoyuanxinwen/'
allnews = alist(listUrl)
for newtro in allnews:
    print(newtro)      

3.生成所页列表页的url并获取全部新闻 ：列表extend(列表) allnews

*每个同学爬学号尾数开始的10个列表页

allnews = []
for i in range(2,12):
    listUrl = 'http://news.gzcc.cn/html/xiaoyuanxinwen/{}.html'.format(i)
    allnews.extend(alist(listUrl))


for n in allnews:
    print(n)
#统计所爬取的新闻总数
print(len(allnews))      

4.设置合理的爬取间隔

import time

import random

time.sleep(random.random()*3)

5.用pandas做简单的数据处理并保存

保存到csv或excel文件 

newsdf.to_csv(r'F:\duym\爬虫\gzccnews.csv')

newsdf = pd.DataFrame(allnews)
for i in range(5):
    print(i)
    time.sleep(random.random() * 3)    print(newsdf)
# 保存到本地csv文件
newsdf.to_csv(r'E:\gzccnews.csv',encoding='utf-8')