Python 爬取51cto博客数据存入MySQL

实验环境

1.安装Python 3.7
2.安装requests, bs4，pymysql 模块

实验步骤

1.安装环境及模块

可参考博客https://blog.51cto.com/13760351/2500048

2.编写代码

# 51cto 博客页面数据插入mysql数据库
# 导入模块
import re
import bs4
import pymysql
import requests

# 连接数据库账号密码
db = pymysql.connect(host='172.171.13.229',
                     user='root', passwd='abc123',
                     db='test', port=3306,
                     charset='utf8')
# 获取游标
cursor = db.cursor()

def open_url(url):
    # 连接模拟网页访问
    headers = {
        'user-agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) '
                      'Chrome/57.0.2987.98 Safari/537.36'}
    res = requests.get(url, headers=headers)
    return res

# 爬取网页内容
def find_text(res):
    soup = bs4.BeautifulSoup(res.text, 'html.parser')

    # 博客名
    titles = []
    targets = soup.find_all("a", class_="tit")
    for each in targets:
        each = each.text.strip()
        if "置顶" in each:
            each = each.split(' ')[0]
        titles.append(each)

    # 阅读量
    reads = []
    read1 = soup.find_all("p", class_="read fl on")
    read2 = soup.find_all("p", class_="read fl")
    for each in read1:
        reads.append(each.text)
    for each in read2:
        reads.append(each.text)

    # 评论数
    comment = []
    targets = soup.find_all("p", class_='comment fl')
    for each in targets:
        comment.append(each.text)

    # 收藏
    collects = []
    targets = soup.find_all("p", class_='collect fl')
    for each in targets:
        collects.append(each.text)

     # 发布时间
    dates=[]
    targets = soup.find_all("a", class_='time fl')
    for each in targets:
        each = each.text.split('：')[1]
        dates.append(each)

    # 插入sql 语句
    sql = """insert into blog (blog_title,read_number,comment_number, collect, dates)
    values( '%s', '%s', '%s', '%s', '%s');"""
    # 替换页面 \xa0
    for titles, reads, comment, collects, dates in zip(titles, reads, comment, collects, dates):
        reads = re.sub('\s', '', reads)
        comment = re.sub('\s', '', comment)
        collects = re.sub('\s', '', collects)
        cursor.execute(sql % (titles, reads, comment, collects，dates))
        db.commit()
        pass

# 统计总页数
def find_depth(res):
    soup = bs4.BeautifulSoup(res.text, 'html.parser')
    depth = soup.find('li', class_='next').previous_sibling.previous_sibling.text
    return int(depth)

# 主函数
def main():
    host = "https://blog.51cto.com/13760351"
    res = open_url(host)  # 打开首页链接
    depth = find_depth(res)  # 获取总页数

    # 爬取其他页面信息
    for i in range(1, depth + 1):
        url = host + '/p' + str(i)  # 完整链接
        res = open_url(url)  # 打开其他链接
        find_text(res)  # 爬取数据

    # 关闭游标
    cursor.close()
    # 关闭数据库连接
    db.close()

if __name__ == '__main__':
    main()

3..MySQL创建对应的表

CREATE TABLE `blog` (
  `row_id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键',
  `blog_title` varchar(52) DEFAULT NULL COMMENT '博客标题',
  `read_number` varchar(26) DEFAULT NULL COMMENT '阅读数量',
  `comment_number` varchar(16) DEFAULT NULL COMMENT '评论数量',
  `collect` varchar(16) DEFAULT NULL COMMENT '收藏数量',
  `dates` varchar(16) DEFAULT NULL COMMENT '发布日期',
  PRIMARY KEY (`row_id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

4.运行代码，查看效果:

改进版：

改进内容：
1.数据库里面的某些字段只保留数字即可
2.默认爬取的内容都是字符串，存放数据库的某些字段，最好改为整型，方便后面数据库操作

1.代码如下：

import re
import bs4
import pymysql
import requests

# 连接数据库
db = pymysql.connect(host='172.171.13.229',
                     user='root', passwd='abc123',
                     db='test', port=3306,
                     charset='utf8')
# 获取游标
cursor = db.cursor()

def open_url(url):
    # 连接模拟网页访问
    headers = {
        'user-agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) '
                      'Chrome/57.0.2987.98 Safari/537.36'}
    res = requests.get(url, headers=headers)
    return res

# 爬取网页内容
def find_text(res):
    soup = bs4.BeautifulSoup(res.text, 'html.parser')

    # 博客标题
    titles = []
    targets = soup.find_all("a", class_="tit")
    for each in targets:
        each = each.text.strip()
        if "置顶" in each:
            each = each.split(' ')[0]
        titles.append(each)

    # 阅读量
    reads = []
    read1 = soup.find_all("p", class_="read fl on")
    read2 = soup.find_all("p", class_="read fl")
    for each in read1:
        reads.append(each.text)
    for each in read2:
        reads.append(each.text)

    # 评论数
    comment = []
    targets = soup.find_all("p", class_='comment fl')
    for each in targets:
        comment.append(each.text)

    # 收藏
    collects = []
    targets = soup.find_all("p", class_='collect fl')
    for each in targets:
        collects.append(each.text)

    # 发布时间
    dates=[]
    targets = soup.find_all("a", class_='time fl')
    for each in targets:
        each = each.text.split('：')[1]
        dates.append(each)

    # 插入sql 语句
    sql = """insert into blogs (blog_title,read_number,comment_number, collect, dates)
    values( '%s', '%s', '%s', '%s', '%s');"""
    # 替换页面 \xa0
    for titles, reads, comment, collects, dates in zip(titles, reads, comment, collects, dates):
        reads = re.sub('\s', '', reads)
        reads=int(re.sub('\D', "", reads))  #匹配数字，转换为整型
        comment = re.sub('\s', '', comment)
        comment = int(re.sub('\D', "", comment))  #匹配数字，转换为整型
        collects = re.sub('\s', '', collects)
        collects = int(re.sub('\D', "", collects))  #匹配数字，转换为整型
        dates = re.sub('\s', '', dates)
        cursor.execute(sql % (titles, reads, comment, collects,dates))
        db.commit()
        pass

# 统计总页数
def find_depth(res):
    soup = bs4.BeautifulSoup(res.text, 'html.parser')
    depth = soup.find('li', class_='next').previous_sibling.previous_sibling.text
    return int(depth)

# 主函数
def main():
    host = "https://blog.51cto.com/13760351"
    res = open_url(host)  # 打开首页链接
    depth = find_depth(res)  # 获取总页数

    # 爬取其他页面信息
    for i in range(1, depth + 1):
        url = host + '/p' + str(i)  # 完整链接
        res = open_url(url)  # 打开其他链接
        find_text(res)  # 爬取数据

    # 关闭游标
    cursor.close()
    # 关闭数据库连接
    db.close()

#主程序入口
if __name__ == '__main__':
    main()

2.创建对应表

CREATE TABLE `blogs` (
  `row_id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键',
  `blog_title` varchar(52) DEFAULT NULL COMMENT '博客标题',
  `read_number` int(26) DEFAULT NULL COMMENT '阅读数量',
  `comment_number` int(16) DEFAULT NULL COMMENT '评论数量',
  `collect` int(16) DEFAULT NULL COMMENT '收藏数量',
  `dates` varchar(16) DEFAULT NULL COMMENT '发布日期',
  PRIMARY KEY (`row_id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

3.运行代码，验证

升级版

为了能让小白就可以使用这个程序，可以把这个项目打包成exe格式的文件，让其他人，使用电脑就可以运行代码，这样非常方便！

1.改进代码：

#末尾修改为：
if __name__ == '__main__':
    main()
    print("\n\t\t所有数据已成功存放数据库！!! \n")
    time.sleep(5)

2.安装打包模块pyinstaller(cmd安装）

pip install pyinstaller -i https://pypi.tuna.tsinghua.edu.cn/simple/

3.Python代码打包

1.切换到需要打包代码的路径下面
2.在cmd窗口运行 pyinstaller -F test03.py （test03为项目名称）

4.查看exe包

在打包后会出现dist目录，打好包就在这个目录里面

5.运行exe包，查看效果

检查数据库

总结：

1.这一篇博客，是在上一篇的基础上改进的，步骤是先爬取首页的信息，再爬取其他页面信息，最后在改进细节，打包exe文件
2.我们爬取网页数据大多数还是存放到数据库的，所以这种方法很实用。
3.其实在此博客的基础上还是可以改进的，重要的是掌握方法即可。