在之前的篇章中，已经补充完成mysql的基本知识，那么现在开始，我们需要把mysql和express,nodejs连接起来。

安装依赖

npm install mysql2 express js-yaml

1. mysql2 用来连接mysql和编写sq语句
2. express 用来提供接口 增删改差
3. js-yaml 用来编写配置文件

编写代码

db.ocnfig.yaml

db:
   host: localhost #主机
   port: 3306 #端口
   user: root #账号
   password: '123456' #密码 一定要字符串
   database: xiaoman # 库

index.js

import mysql2 from 'mysql2/promise'
import fs from 'node:fs'
import jsyaml from 'js-yaml'
import express from 'express'
const yaml = fs.readFileSync('./db.config.yaml', 'utf8')
const config = jsyaml.load(yaml)
const sql = await mysql2.createConnection({
   ...config.db
})
const app = express()
app.use(express.json())
//查询接口 全部
app.get('/',async (req,res)=>{
   const [data] = await sql.query('select * from user')
   res.send(data)
})
//单个查询 params
app.get('/user/:id',async (req,res)=>{
    const [row] = await sql.query(`select * from user where id = ?`,[req.params.id])
    res.send(row)
})

//新增接口
app.post('/create',async (req,res)=>{
    const {name,age,hobby} = req.body
    await sql.query(`insert into user(name,age,hobby) values(?,?,?)`,[name,age,hobby])
    res.send({ok:1})
})

//编辑
app.post('/update',async (req,res)=>{
    const {name,age,hobby,id} = req.body
    await sql.query(`update user set name = ?,age = ?,hobby = ? where id = ?`,[name,age,hobby,id])
    res.send({ok:1})
})
//删除
app.post('/delete',async (req,res)=>{
    await sql.query(`delete from user where id = ?`,[req.body.id])
    res.send({ok:1})
})
const port = 3000

app.listen(port, () => {
   console.log(`Example app listening on port ${port}`)
})

index.http

方便测试接口

# 查询全部
 GET http://localhost:3000/ HTTP/1.1

# 单个查询
GET http://localhost:3000/user/2 HTTP/1.1

# 添加数据
POST http://localhost:3000/create HTTP/1.1
Content-Type: application/json

{
    "name":"张三",
    "age":18
}

# 更新数据
POST http://localhost:3000/update HTTP/1.1
Content-Type: application/json

{
    "name":"法外狂徒",
    "age":20,
    "id":23
}


#删除
# POST http://localhost:3000/delete HTTP/1.1
# Content-Type: application/json

# {
#     "id":24
# }

后续更新计划