这两天写一个小项目，不想用PHP写接口，太繁重。看了一圈后端云，发现都不咋运营了，进而打算自己写吧。然后看了nodejs，发现很轻量，而且还是js语言，这不是正好合我意，然后就开始研究起来。

const express = require("express")
const app = express()
const mysql2 = require("mysql2")

app.get("/", async (req, res) => {
    // 跨域
    res.setHeader('Access-Control-Allow-Origin', '*');
    res.setHeader("Access-Control-Allow-Headers", "X-Requested-With");
    res.setHeader("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE,OPTIONS");
    // 创建连接池
    const config = getDBConfig()
    const promisePool = mysql2.createPool(config).promise()
    let urls = req.query
    var name = null;//用来记录第一个键值对的值
    for (var key in urls) {
        name = urls[key];
        break;
    }
    console.log(name, "url参数");
    let lit = await promisePool.query(`select * from one where name like "%${name}%"`)
    console.log(lit, '结果');
    res.send(lit);
}).listen(3000)

function getDBConfig() {
    return {
        host: "127.0.0.1",
        port: 3306,
        user: "root",
        password: "root",
        database: "instructions",
        connectionLimit: 1    //连接池
    }
}