无法读取 undefined sequelize express JS 的属性“findAll”并且 req.body 是一个空对象

Question

I'm having trouble taking the data from the table and creating an API. The table isn't empty but req.body is and it says Vehicle is undefined ? The exact Error message I get is "TypeError: Cannot read property 'findAll' of undefined" and the req.body response is an empty object.

Please help, I've tried everything.

Model:

 import { Model } from 'sequelize'; const PROTECTED_ATTRIBUTES = ['password']; export default (sequelize, DataTypes) => { class Vehicles extends Model { toJSON() { // hide protected fields const attributes = { ...this.get() }; // eslint-disable-next-line no-restricted-syntax for (const a of PROTECTED_ATTRIBUTES) { delete attributes[a]; } return attributes; } /** * Helper method for defining associations. * This method is not a part of Sequelize lifecycle. * The `models/index` file will call this method automatically. */ static associate(vehicles) { // define association here } }; Vehicles.init({ // id: DataTypes.INTEGER, make: DataTypes.STRING, model: DataTypes.STRING, createdAt: DataTypes.DATE, updatedAt: DataTypes.DATE }, { sequelize, modelName: 'Vehicles', }); return Vehicles; };

Models/index.js:

 import fs from 'fs'; import path from 'path'; import Sequelize from 'sequelize'; import enVariables from '../config/config.json'; const basename = path.basename(__filename); const env = process.env.NODE_ENV || 'development'; const config = enVariables[env]; const db = {}; let sequelize; if (config.use_env_variable) { sequelize = new Sequelize(process.env[config.use_env_variable], config); } else { sequelize = new Sequelize(config.database, config.username, config.password, config); } fs .readdirSync(__dirname) .filter(file => (file.indexOf('.') !== 0) && (file !== basename) && (file.slice(-3) === '.js')) .forEach(file => { // eslint-disable-next-line global-require,import/no-dynamic-require const model = require(path.join(__dirname, file)).default(sequelize, Sequelize.DataTypes); db[model.name] = model; }); Object.keys(db).forEach(modelName => { if (db[modelName].associate) { db[modelName].associate(db); } }); db.sequelize = sequelize; db.Sequelize = Sequelize; export default db;

Index.js:

 const express = require('express'); const models = require('./src/models'); const Vehicles = models.Vehicles; const app = express(); var bodyParser = require('body-parser'); const jsonParser = bodyParser.json(); app.use(bodyParser.urlencoded({ extended: true })) app.use(bodyParser.json()) app.get('/', function(req, res){ res.send('Hello, please go to /vehicles !') }) app.get('/vehicles', jsonParser, async function(req ,res){ // res.send('page under construction') // console.log(Vehicles.findOne()) Vehicles.findAll().then(users => { return users }); }); const port = 5000; app.listen(port, () => { console.log('App is now running at port ', port) })

Answer 1

Issue has been solved, it is because I was using EcmaScript modules ( export , import ) in models/index.js , then importing it using CommonJS ( module.exports , require ) in index.js. That caused issues. I should have used the same module format on both sides, or console.log what require('./src/models') outputs to debug it.

I changed:

const models = require('./src/models')

To:

const models = require('./src/models').default;

but I ideally should only use one module format