确保已安装node
创建项目文件夹,并初始化
npm init -y 

安装express
npm install express  
安装mysql
npm install mysql 
安装body-parser
npm install body-parser 
新建db/mysql.js
const mysql = require('mysql');
let db = mysql.createConnection({
    host: '127.0.0.1',
    user: 'root',
    password: '123456',
    database: 'demo_data',
    port: 3306
});
db.connect(function (err) {
    if (err) {
        console.log("err" + err.stack);
        return;
    }
    console.log("connection id " + db.threadId);
});
module.exports = db; 
新建 app.js
const express = require('express');
const app = new express();
const db = require('./db/mysql');
const bodyParser = require('body-parser');
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended: true}));
app.use(express.static(__dirname + '/'));
app.listen(3002, () => {
    console.log('服务已启动, 监听端口是 3002');
});
// 查询所有用户和密码
app.get('/api/user', (req, res) => {
    const sqlStr = 'SELECT * FROM sys_user;'
    db.query(sqlStr, (err, results) => {
        // 查询数据失败
        if (err) {
            return console.log(err.message)
        } else {
            res.send({
                status: 200,
                message: '获取所有用户成功',
                data: results,
            })
        }
    })
})
module.exports = app; 
目录结构如下:

启动服务:
node app.js 

测试服务:
 



















