正则表达式实战

0x00 股票数据定向爬虫

---

功能描述：

• 目标：获取上交所和深交所所有股票名称和交易信息
• 输出：保存到文件中
• 技术路线：requests-bs4-re

                                        

程序结构设计：

　　步骤1：从东方财富网获取股票列表

　　步骤2：根据股票列表逐个到百度股票获取个股信息

　　步骤3：将结果存储到文件

import requests
import traceback
from bs4 import BeautifulSoup
import re

def getHTMLText(url):                         #获取页面信息经典框架
    try:
        r = requests.get(url, timeout = 30)
        r.raise_for_status()
        r.encoding = r.apparent_encoding
        return r.text
    except:
        return ""

def getStockList(lst, stockUrl):               #从东方财富网获取股票代码，以便构造之后的url
    html = getHTMLText(stockUrl)
    soup = BeautifulSoup(html, 'html.parser')
    a = soup.find_all('a')
    for i in a:                                #对于每个a标签，从其href属性的值中提取s开头后面为h或z加上6位数字的代码
        try:
            href = i.attrs['href']
            lst.append(re.findall(r'[s][hz]d{6}', href)[0])
        except:
            continue

def getStockInfo(lst, stockURL, fpath):        #获取之前列表中的股票信息
    for stock in lst:                          #遍历之前获得的股票代码，构造新url，访问百度股票
        url = stockURL + stock + '.html'
        html = getHTMLText(url)
        try:                                   
            if html == "":
                continue
            infoDick = {}                      #新建字典存储股票信息
            soup = BeautifulSoup(html, 'html.parser')
            stockInfo = soup.find('div', attrs={'class' : 'stock-bets'})      

            name = stockInfo.find_all(attrs={'class': 'bets-name'})[0]        #获取股票名称
            infoDick.update({'股票名称' : name.text.split()[0]})

            keyList = stockInfo.find_all('dt')                                #获取对应股票的相关信息
            valueList = stockInfo.find_all('dd')
            for i in range(len(keyList)):
                key = keyList[i].text
                value = valueList[i].text
                infoDick[key] = value

            with open(fpath, 'a', encoding='utf-8') as f:                      #存储在本机文件中
                f.write(str(infoDick) + '
')
        except:
            traceback.print_exc()
            continue


def main():
    stock_list_url = "http://quote.eastmoney.com/stocklist.html"
    stock_info_url = "https://gupiao.baidu.com/stock/"
    output_file = "D://BaiduStockInfo.txt"
    slist = []
    getStockList(slist, stock_list_url)
    getStockInfo(slist, stock_info_url, output_file)

main()

 代码优化：

因为我们做的是定向爬取，因此两个url页面的编码我们都可以首先经过手工确定，直接查看源码，我们在数据头部分发现百度股票的编码为utf-8，东方财富网编码为gb2312，因此在getHTMLText()函数中，不用apparent_encoding方法去动态获取头文件中的编码，可以直接给编码赋值来提速：

def getHTMLText(url, code = 'utf-8'):
    try:
        r = requests.get(url, timeout = 30)
        r.raise_for_status()
        r.encoding = code
        return r.text
    except:
        return ""

def getStockList(lst, stockUrl):               
    html = getHTMLText(stockUrl, "GB2312")
    soup = BeautifulSoup(html, 'html.parser')
    a = soup.find_all('a')
    for i in a:                               
        try:
            href = i.attrs['href']
            lst.append(re.findall(r'[s][hz]d{6}', href)[0])
        except:
            continue

def getStockInfo(lst, stockURL, fpath):        
    for stock in lst:                         
        url = stockURL + stock + '.html'
        html = getHTMLText(url)

同时我们可以打印动态进度条，来提高用户体验

def getStockInfo(lst, stockURL, fpath):
    count = 0
    for stock in lst:
        url = stockURL + stock + '.html'
        html = getHTMLText(url)
        try:
            if html == "":
                continue
            infoDick = {}
            soup = BeautifulSoup(html, 'html.parser')
            stockInfo = soup.find('div', attrs={'class' : 'stock-bets'})

            name = stockInfo.find_all(attrs={'class': 'bets-name'})[0]
            infoDick.update({'股票名称' : name.text.split()[0]})

            keyList = stockInfo.find_all('dt')
            valueList = stockInfo.find_all('dd')
            for i in range(len(keyList)):
                key = keyList[i].text
                value = valueList[i].text
                infoDick[key] = value

            with open(fpath, 'a', encoding='utf-8') as f:
                f.write(str(infoDick) + '
')
                count = count + 1
                print("
当前进度: {:.2f}%".format(count * 100 / len(lst)), end="")
        except:
            count = count + 1
            print("
当前进度: {:.2f}%".format(count * 100 / len(lst)), end="")
            continue