python：Flask框架（三）pymysql 连接 MySQL 实现简单登录（mvc模式）

╰+攻爆jí腚メ 2023-10-05 11:46 17阅读 0赞

根据前两篇文章，已经可以利用 Flask 实现简单的路由访问，接下来结合 mysql 实现简单的登录。

###### 新建一个名为 python\_test 的数据库， 添加 user 表 ######

CREATE DATABASE /*!32312 IF NOT EXISTS*/`python_test` /*!40100 DEFAULT CHARACTER SET utf8 */ /*!80016 DEFAULT ENCRYPTION='N' */;
    
    USE `python_test`;
    
    /*Table structure for table `user` */
    
    DROP TABLE IF EXISTS `user`;
    
    CREATE TABLE `user` (
      `id` int NOT NULL AUTO_INCREMENT,
      `name` varchar(10) DEFAULT NULL,
      `password` varchar(10) DEFAULT NULL,
      PRIMARY KEY (`id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8;
    
    /*Data for the table `user` */
    
    insert  into `user`(`id`,`name`,`password`) values (1,'admin','123456'),(5,'oppo','456789'),(6,'vivo','987654'),(7,'huawei','');

###### 文件结构如下所示 ######

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3_size_16_color_FFFFFF_t_70_pic_center]

###### 新建登陆页面 index.html ######

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>登录</title>
    </head>
    <body>
    <form action="/login" method="post">
        <div style="position: absolute;margin-left: 750px;margin-top: 350px">
            <p>姓名：<input type="text" name="name"></p>
            <p>密码：<input type="password" name="password"></p>
            <p><input type="submit" value="登录" style="position: absolute;margin-left: 90px"></p>
        </div>
    </form>
    </body>
    </html>

###### 新建登陆成功页面 success.html ######

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>首页</title>
    </head>
    <body>
    <p>欢迎你{
       {name}}
        <button onclick="back()">退出登录</button>
    </p>
    </body>
    </html>
    <script>
        function back() {
         
            history.back();
        }
    </script>

###### 新建 user\_model.py 实体类和数据库 user 表对应 ######

class User:
        i_d = 0
        name = ''
        password = ''
    
        def __init__(self, i_d, name, password):
            self.id = i_d
            self.name = name
            self.password = password

###### 新建 user\_mysql.py 连接查询数据库 ######

import pymysql
    
    def get_by_name(name):
        conn = pymysql.connect(host='127.0.0.1', user='root', password='123456', database='python_test', charset='utf8')
        cursor = conn.cursor()
        sql = "select * from user where name='%s'" % name
        # sql = "select * from user"
        cursor.execute(sql)
        results = format_data(cursor.description, cursor.fetchall())
        cursor.close()
        conn.close()
        return results
    
    # 数据格式化 fields 字段名，result 结果集
    def format_data(fields, result):
        # 列字段数组 格式['id', 'name', 'password']
        field = []
        for i in fields:
            field.append(i[0])
        # 返回的数组集合 格式[{'id': 1, 'name': 'admin', 'password': '123456'}]
        results = []
        for res in result:
            line_data = {
        }
            for index in range(0, len(field)):
                line_data[field[index]] = res[index]
            results.append(line_data)
        return results

###### 新建 user\_dao 处理登录业务逻辑 ######

import user_mysql, user_model
    
    def login_dao(name, password):
        if len(user_mysql.get_by_name(name)) > 0:
            res = user_mysql.get_by_name(name)[0]
            user = user_model.User(i_d=res['id'], name=res['name'], password=res['password'])
            if user.name == name and user.password == password:
                return 1
            else:
                return '密码错误'
        return '用户名不存在'

###### 新建 user\_controller 控制路由跳转及视图展示 ######

from flask import Flask, url_for, redirect, request, render_template
    import user_dao
    
    app = Flask('__name__')
    
    @app.route('/login', methods=['POST', 'GET'])
    def login():
        if request.method == 'POST':
            flag = user_dao.login_dao(request.form['name'], request.form['password'])
            print(flag)
            if flag == 1:
                return redirect(url_for('success', name=request.form['name']))
            else:
                return redirect(url_for(endpoint='fail', msg=flag))
        else:
            return render_template('404.html')
    
    # @app.route('/success/<name>/<address>/<int:age>')
    # def success(name, address, age):
    #     return '欢迎你%s,地址：%s,年龄：%d' % (name, address, age)
    app.add_url_rule(rule='/success/<name>', view_func=success)
    def success(name):
        return render_template('success.html', name=name)
    
    @app.route('/fail/<msg>')
    def fail(msg):
        return "<font color='red'>登陆失败：  %s</font>" % msg
    
    @app.route('/')
    def index():
        return render_template('index.html')
    
    if __name__ == '__main__':
        app.run(host='127.0.0.1', port=5000, debug=False)

以上代码都是一些简单逻辑就不过多解释了，下面运行测试

运行 user\_controller.py 文件  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3_size_16_color_FFFFFF_t_70_pic_center 1]  
浏览器打开网址： [http://127.0.0.1:5000/][http_127.0.0.1_5000]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3_size_16_color_FFFFFF_t_70_pic_center 2]

###### 测试登录---->登陆成功 ######

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3_size_16_color_FFFFFF_t_70_pic_center 3]

###### 测试登录---->登陆失败 ######

![在这里插入图片描述][20201016141010645.png_pic_center]

![在这里插入图片描述][20201016123059539.png_pic_center]  
如上，就简单实现了 Flask + pymysql 简单登录。

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3_size_16_color_FFFFFF_t_70_pic_center]: https://img-blog.csdnimg.cn/20201016123215889.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3,size_16,color_FFFFFF,t_70#pic_center
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3_size_16_color_FFFFFF_t_70_pic_center 1]: https://img-blog.csdnimg.cn/2020101611482527.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3,size_16,color_FFFFFF,t_70#pic_center
[http_127.0.0.1_5000]: http://127.0.0.1:5000/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3_size_16_color_FFFFFF_t_70_pic_center 2]: https://img-blog.csdnimg.cn/20201016115306668.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3,size_16,color_FFFFFF,t_70#pic_center
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3_size_16_color_FFFFFF_t_70_pic_center 3]: https://img-blog.csdnimg.cn/2020101611554033.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTM4MDk3,size_16,color_FFFFFF,t_70#pic_center
[20201016141010645.png_pic_center]: https://img-blog.csdnimg.cn/20201016141010645.png#pic_center
[20201016123059539.png_pic_center]: https://img-blog.csdnimg.cn/20201016123059539.png#pic_center