NodeJs(express)之ORM组件sequelize

安装依赖包

## 为了方便写API我引入了express
npm i express
npm i sequelize
npm i mysql2

新建appConfig.js用于读取多环境下的配置

const AppConfig = {
    nodeEnv: process.env.NODE_ENV,
    nodeHost: process.env.SERVER_HOST,
    nodePort: process.env.SERVER_PORT,

    dbHost: process.env.DB_HOST,
    dbName: process.env.DB_NAME,
    dbPort: process.env.DB_PORT,
    dbUser: process.env.DB_USER,
    dbPassword: process.env.DB_PASSWORD,
    dbDialect: process.env.DB_DIALECT,

    dbPoolMax: parseInt(process.env.DB_POOL_MAX),
    dbPoolMin: parseInt(process.env.DB_POOL_MIN),
    dbPoolIdle: parseInt(process.env.DB_POOL_IDLE)
};

module.exports = AppConfig

新建db.js用于数据库建立连接

const Sequelize = require('sequelize')
const AppConfig = require('./appConfig')

const sequelize = new Sequelize(AppConfig.dbName, AppConfig.dbUser, AppConfig.dbPassword, {
    host: AppConfig.dbHost,
    port: AppConfig.dbPort,
    dialect: AppConfig.dbDialect,
    pool: {
        max: AppConfig.dbPoolMax,
        min: AppConfig.dbPoolMin,
        idle: AppConfig.dbPoolIdle
    },
    logging: true
});

sequelize
  .authenticate()
  .then(() => {
    console.log('Connection has been established successfully.');
  })
  .catch(err => {
    console.error('Unable to connect to the database:', err);
  });

module.exports = sequelize;

新建数据实体类，此类与数据库表对应

const { Sequelize, Model} = require('sequelize');
const sequelize = require('../db')


class User extends Model {}

User.init({
    id : {
      type: Sequelize.INTEGER,
      field: 'id',
      autoIncrement: true,
      primaryKey: true,
      allowNull: false
    },
    name: {
      type: Sequelize.STRING,
      allowNull: false
    },
    password: {
      type: Sequelize.STRING,
      allowNull: false
    },
    age: {
      type: Sequelize.INTEGER,
      allowNull: false
    }
  },
  {
    sequelize: sequelize,
    // 数据库表名称
    tableName: 'user',
    // 不自动生成createdate\update时间字段值
    timestamps: false
  }
)

module.exports = User

在router文件夹下新建文件userRouter.js，在service文件夹下新建文件userService.js

userRouter.js

const express = require('express')
const urouter = express.Router()
const UserService = require('../service/userService')

 urouter.get('/user/:name', async (req, res) => {
  console.log('*** ' + req.params.name)
  let user = await UserService.getUserByName(req.params.name);
  res.send(user)
})

module.exports = urouter

userService.js

const User = require('../model/user')

exports.getUserByName = async name => {
  console.log(name);
  let user = await User.findOne({
    where: {
      name: name
    },
  });

  return user;
}

注册路由

index.js

const express = require('express')
const app = express()

const NODE_ENV = process.env.NODE_ENV
const dotenvFile = NODE_ENV? `.env.${NODE_ENV}` : '.env'
require('dotenv').config({path: dotenvFile})
const AppConfig = require('./appConfig')
const Host = AppConfig.nodeHost
const Port = AppConfig.nodePort
const urouter = require('./router/userRouter')

// 注册路由中间件, 并给所有API添加统一前缀 /api
app.use('/api', urouter)

app.listen(Port, () => console.log(`server address: http://${Host}:${Port} !`))

访问接口

http://localhost:3000/api/user/xiao

{
"id": 1,
"name": "xiao",
"password": "123456",
"age": 12
}