一文聊聊node怎麼封裝mysql處理語句

npm i mysql -S
npm i express -S

const mysql = require('mysql')function createConnection() {
    const connection = mysql.createConnection({
        host: '',  //地址
        user: '',  //使用者名稱
        password: '',  //密碼
        port: '',  //埠
        database: ''  //資料庫名
    });
    return connection;}module.exports.createConnection = createConnection;

const mysql = require('../mysql/mysql')let connection = null;connection = mysql.createConnection();/**
 * 錯誤訊息
 */let bad_msg = {
    code: 500,
    msg: '內部錯誤！'}/**
 * 成功訊息
 */let success_msg = {
    code: 200,
    msg: '操作成功'}const connections = {
    /**
     * 查詢方法
     * @param {*} table 表名
     * @param {*} condition 條件
     * @param {*} params 引數
     * @param {*} search 查詢條件
     * @returns 
     */
    find(table, condition, params, search = '*') {
        return new Promise((resolve, reject) => {
            let sql = `SELECT ${search} FROM ${table} WHERE ${condition}`
            connection.query(sql, params, (err, result) => {
                if (err) {
                    reject(bad_msg)
                } else {
                    let _ = JSON.parse(JSON.stringify(success_msg))
                    _.data = result                    resolve(_)
                }
            })
        })
    },
    /**
     * 插入方法
     * @param {*} table 表名
     * @param {*} condition 條件
     * @param {*} params 引數
     * @returns 
     */
    insert(table, condition, params) {
        return new Promise((resolve, reject) => {
            const str = "?"
            let _ = str.repeat((condition.split(',')).length)
            let val = (Array.from(_)).toString()
            let sql = `INSERT INTO ${table}(${condition}) VALUES(${val})`
            connection.query(sql, params, (err, result) => {
                if (err) {
                    reject(bad_msg)
                } else {
                    resolve(success_msg)
                }
            })
        })
    },
    /**
     * 更新方法
     * @param {*} table 表名
     * @param {*} val 值
     * @param {*} condition 條件
     * @param {*} params 引數
     * @returns 
     */
    update(table, val, condition, params) {
        return new Promise((resolve, reject) => {
            let sql = `UPDATE ${table} SET ${val} WHERE ${condition}`
            connection.query(sql, params, (err, result) => {
                if (err) {
                    reject(bad_msg)
                } else {
                    resolve(success_msg)
                }
            })
        })
    },
    /**
     * 刪除方法
     * @param {*} table 表名
     * @param {*} condition 條件
     * @param {*} params 引數
     * @returns 
     */
    del(table, condition, params) {
        return new Promise((resolve, reject) => {
            let sql = `DELETE FROM ${table} WHERE ${condition}`
            connection.query(sql, params, (err, result) => {
                if (err) {
                    reject(bad_msg)
                } else {
                    resolve(success_msg)
                }
            })
        })
    },}module.exports = connections

const express = require('express')const router = express.Router()const connections = require('../../static/connection')// token生成外掛模組const jwt = require('jsonwebtoken');// Token簽名var secret = ''const CreatId = require('../../static/ranId')router.post('/user/details', (req, res) => {
    connections.find('user_table', `ID=?`,req.user.ID).then(resp => {
        res.send(resp)
    })})router.post('/api/login', (req, res) => {
    connections.find('user_table', 'user=?', req.body.user).then(resp => {
        let {data} = resp        if (data.length !== 0) {
            for (let i = 0; i < data.length; i++) {
                // 郵箱或者密碼不正確的時候
                if (req.body.user !== data[i].user || req.body.pwd !== data[i].pwd) {
                    res.send({
                        code: 202,
                        msg: '使用者名稱或密碼有誤!'
                    })
                } else {
                    // 郵箱和密碼輸入正確
                    if (req.body.user === data[i].user && req.body.pwd === data[i].pwd) {
                        // 傳輸的token內容
                        let token = jwt.sign({ ID: data[i].ID }, secret, { expiresIn: '72H' });
                        // 返回結果
                        res.send({
                            code: 200,
                            msg: '操作成功！',
                            token: 'Bearer ' + token,
                        })
                    }
                }
            }
        } else {
            res.send({
                code: 400,
                msg: '賬號不存在請註冊!'
            })
        }
    }).catch(e => {
        res.send(e)
    })})router.post('/api/register', (req, res) => {
    connections.find('user_table', 'user=?', req.body.user).then(resp => {
        if (resp.data.length > 0) {
            res.send({
                code: 202,
                msg: '該使用者已經存在！'
            })
        } else {
            let _ = req.body            let id = CreatId(3) + CreatId(3)
            connections.insert('user_table', 'ID,user,pwd,avatarUrl,location,RegisterTime,isAdmin,isDel', [id, _.user, _.pwd, '/static/userimg/user.webp', _.location, Date.now(), 0, 0]).then(resps => {
                // 傳輸的token內容
                let token = jwt.sign({ ID: id }, secret, { expiresIn: '72H' });
                // 返回結果
                res.send({
                    code: 200,
                    msg: '操作成功！',
                    token: 'Bearer ' + token,
                })
            })
        }
    })})module.exports = router