數據結構化與保存

1. 將新聞的正文內容保存到文本文件。

import requests
from bs4 import BeautifulSoup

url = "http://news.gzcc.cn/html/xiaoyuanxinwen/"
res = requests.get(url)
res.encoding = "utf-8"
soup = BeautifulSoup(res.text, "html.parser")

def writeNewsDetails(contents):
    f = open('gzccnews.txt', "a", encoding="utf-8")
    f.write(contents)
    f.close()

2. 將新聞數據結構化爲字典的列表:

• 單條新聞的詳情-->字典news
• 一個列表頁全部單條新聞彙總-->列表newsls.append(news)
• 全部列表頁的全部新聞彙總列表newstotal.extend(newsls)

  def getClickCount(newUrl):
      newsId = re.findall("\_(.*).html", newUrl)[0].split("/")[-1]
      res = requests.get("http://oa.gzcc.cn/api.php?op=count&id= {}&modelid=80".format(newsId))
      return int(res.text.split(".html")[-1].lstrip("('").rsplit("');")[0])
  
  def getNewDetails(newsDetailUrl):
      detail_res = requests.get(newsDetailUrl)
      detail_res.encoding = "utf-8"
      detail_soup = BeautifulSoup(detail_res.text, "html.parser")
      news = {}
      news['title'] = detail_soup.select(".show-title")[0].text
      info = detail_soup.select(".show-info")[0].text
      news['date_time'] = datetime.strptime(info.lstrip('發佈時間:')[:19], "%Y-%m-%d %H:%M:%S")
      if info.find('來源：') > 0:
          news['source'] = info[info.find("來源："):].split()[0].lstrip('來源：')
      else:
          news['source'] = 'none'
      news['content'] = detail_soup.select("#content")[0].text
      news['click'] = getClickCount(newsDetailUrl)
      return news
  
  def getPageN(url):
      res = requests.get(url)
      res.encoding = 'utf-8'
      soup = BeautifulSoup(res.text, 'html.parser')
      return int(soup.select(".a1")[0].text.rstrip("條")) // 10 + 1
  
  def getListPage(url):
      newsList = []
      for news in soup.select("li"):
          if len(news.select(".news-list-title")) > 0:
              detail_url = news.select('a')[0].attrs['href']
              newsList.append(getNewDetails(detail_url))
              return newsList
  
  newsTotal = []
  totalPageNum = getPageN(url)
  firstPageUrl = "http://news.gzcc.cn/html/xiaoyuanxinwen/"
  newsTotal.extend(getListPage(firstPageUrl))
  
  for num in range(totalPageNum, totalPageNum + 1):
      listpageurl = "http://news.gzcc.cn/html/xiaoyuanxinwen/{}.html".format(num)
      getListPage(listpageurl)

   

3. 安裝pandas，用pandas.DataFrame(newstotal)，建立一個DataFrame對象df.

df = pandas.DataFrame(newsTotal)
print(df)

4. 經過df將提取的數據保存到csv或excel 文件。

df.to_excel('gzcss.xlsx')

5. 用pandas提供的函數和方法進行數據分析：

• 提取包含點擊次數、標題、來源的前6行數據
• 提取‘學校綜合辦’發佈的，‘點擊次數’超過3000的新聞。
• 提取'國際學院'和'學生工做處'發佈的新聞。
• 進取2018年3月的新聞

  print(df[['title','clickCount','source']][:6])
  print(df[(df['clickCount']>3000)&(df['source']=='學校綜合辦')])
  sou = ['國際學院','學生工做處']
  print(df[df['source'].isin(sou)])
  df1 = df.set_index('time')
  print(df1['2018-03'])

6. 保存到sqlite3數據庫

import sqlite3
with sqlite3.connect('gzccnewsdb.sqlite') as db:
df3.to_sql('gzccnews05',con = db, if_exists='replace')

7. 從sqlite3讀數據

with sqlite3.connect('gzccnewsdb.sqlite') as db:
df2 = pandas.read_sql_query('SELECT * FROM gzccnews05',con=db)
print(df2)

8. df保存到mysql數據庫

安裝SQLALchemy
安裝PyMySQL
MySQL裏建立數據庫：create database gzccnews charset utf8;

MySQL裏查看已保存了數據。（經過MySQL Client或Navicate。）

import pymysql
from sqlalchemy import create_engine
conn = create_engine('mysql+pymysql://root:root@localhost:3306/gzccnews?charset=utf8')
pandas.io.sql.to_sql(df, 'gzccnews', con=conn, if_exists='replace')