为什么使用Sequelize迁移创建表，但模型无法连接到数据库-电脑我帮您

为什么使用Sequelize迁移创建表，但模型无法连接到数据库

我正在学习如何在Node.js中使用Sequelize ORM并将数据保存在Postgres数据库中。

我的目标是将用户数据插入到[[Users表中。我已经使用迁移创建了表格，并且可以正常工作。但是，我无法保存用户数据。我已经关注了许多资源，例如Tut 1 Tut 2等。，我仍然遇到相同的错误

C:\Users\HP\Desktop\path\project\Tutorials\react-project\chat_app_api\database\models\index.js:12 if (config.use_env_variable) { ^ TypeError: Cannot read property 'use_env_variable' of undefined at Object.<anonymous> (C:\Users\HP\Desktop\path\project\Tutorials\react-project\chat_app_api\database\models\index.js:12:12) at Module._compile (internal/modules/cjs/loader.js:776:30) at babelWatchLoader (C:\Users\HP\Desktop\path\project\Tutorials\react-project\chat_app_api\node_modules\babel-watch\runner.js:51:13) at Object.require.extensions.(anonymous function) [as .js] (C:\Users\HP\Desktop\path\project\Tutorials\react-project\chat_app_api\node_modules\babel-watch\runner.js:62:7) at Module.load (internal/modules/cjs/loader.js:653:32) at tryModuleLoad (internal/modules/cjs/loader.js:593:12) at Module.require (internal/modules/cjs/loader.js:690:17) at require (internal/modules/cjs/helpers.js:25:18) at Object.<anonymous> (C:\Users\HP\Desktop\Andela\project\Tutorials\react-project\chat_app_api\server\server.js:1:1) at Module._compile (internal/modules/cjs/loader.js:776:30) at babelWatchLoader (C:\Users\HP\Desktop\path\project\Tutorials\react-project\chat_app_api\node_modules\babel-watch\runner.js:51:13) at Object.require.extensions.(anonymous function) [as .js] (C:\Users\HP\Desktop\path\project\Tutorials\react-project\chat_app_api\node_modules\babel-watch\runner.js:62:7)
配置/ config.js
require('dotenv').config(); module.exports = { development: { use_env_variable: 'DATABASE_URL_DEV', dialect: 'postgres', }, test: { use_env_variable: 'DATABASE_URL_TEST', dialect: 'postgres', }, production: { use_env_variable: 'DATABASE_URL', dialect: 'postgres', ssl: true, dialectOptions: { ssl: true, }, }, };
迁移/ 20190927083519创建-user.js的
'use strict'; module.exports = { up: (queryInterface, Sequelize) => { return queryInterface.createTable('Users', { id: { allowNull: false, primaryKey: true, type: Sequelize.UUID, defaultValue: Sequelize.UUIDV4, }, fullname: { type: Sequelize.STRING }, email: { type: Sequelize.STRING }, password: { type: Sequelize.STRING }, username: { type: Sequelize.STRING }, telephone: { type: Sequelize.STRING }, image: { type: Sequelize.STRING }, createdAt: { allowNull: false, type: Sequelize.DATE }, updatedAt: { allowNull: false, type: Sequelize.DATE } }); }, down: (queryInterface, Sequelize) => { return queryInterface.dropTable('Users'); } };
型号/ index.js
'use strict'; const fs = require('fs'); const path = require('path'); const Sequelize = require('sequelize'); const basename = path.basename(__filename); const env = process.env.NODE_ENV || 'development'; const config = require(__dirname + '/../config/config.js')[env]; // why this return Undefined ? 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 => { return (file.indexOf('.') !== 0) && (file !== basename) && (file.slice(-3) === '.js'); }) .forEach(file => { const model = sequelize['import'](path.join(__dirname, file)); db[model.name] = model; }); Object.keys(db).forEach(modelName => { if (db[modelName].associate) { db[modelName].associate(db); } }); db.sequelize = sequelize; db.Sequelize = Sequelize; module.exports = db;
型号/用户
'use strict'; module.exports = (sequelize, DataTypes) => { const User = sequelize.define('User', { id: { type: DataTypes.UUID, defaultValue: DataTypes.UUIDV4, primaryKey: true, }, fullname: DataTypes.STRING, email: DataTypes.STRING, password: DataTypes.STRING, username: DataTypes.STRING, telephone: DataTypes.STRING, image: DataTypes.STRING }, {}); User.associate = function (models) { // associations can be defined here }; return User; };
app.js
import express from 'express'; import cors from 'cors'; import morgan from 'morgan'; import bodyParser from 'body-parser'; import { errors } from 'celebrate'; import routes from './Routes/index'; const app = express(); app.use(cors()); app.use(morgan('combined')); app.use(bodyParser.urlencoded({ extended: true })); app.use(bodyParser.json()); app.use('/api', routes); app.use(errors()); app.use((req, res) => { const error = new Error('Route not found'); error.status = 404; return res.status(error.status).json({ status: error.status, message: error.message, }); }); // Server Error app.use((error, req, res) => { const status = error.status || 500; return res.status(status).json({ status, message: error.message || 'Server error', }); }); export default app;
ENV
DATABASE_URL_DEV=postgres://postgres:.@localhost:5432/db_dev DATABASE_URL_TEST=postgres://postgres:.@localhost:5432/db_test DATABASE_URL=postgres://user:password@host:5432/db_remote
控制器/ userControllers.js
import bcrypt from 'bcrypt'; import jwt from 'jsonwebtoken'; import dotenv from 'dotenv'; import models from '../../database/models'; import uploadImage from '../Helpers/upload.Image'; dotenv.config(); class UserController { static async signup(req, res) { const { body: input } = req; input.password = bcrypt.hashSync(input.password, 10); try { const image = await uploadImage(req, res); const { secure_url: img } = await image; input.image = img; console.log('result before ########################', models.User); // Undefined const result = await models.User.create(input); console.log('result after ########################', result); // Error here delete result.dataValues.password; const token = jwt.sign(result.dataValues, process.env.SECRET_KEY, { expiresIn: '1W' }); result.dataValues.token = token; const status = 201; return res.status(status).json({ status, message: 'User successfully created', data: result.dataValues, }); } catch (error) { console.log('error########################', error); let { message } = error.errors[0]; const status = 500; message = message || 'Server error'; return res.status(status).json({ status, message, }); } } } export default UserController;
我仍然不知道为什么在
models / index.js
中，我的config变量返回未定义。require(__dirname + '/../config/config.js') // return object env // return environment const config = require(__dirname + '/../config/config.js')[env]; //return Undefined
我花了3天的调试时间，但无法解决错误。任何帮助，都非常感谢指导。
感谢
回答如下：Guyz，我找到了解决问题的方法，

在

models / index.js]中>我将

process.env.NODE_ENV

更改为process.env.NODE_ENV.trim（）'use strict'; const fs = require('fs'); const path = require('path'); const Sequelize = require('sequelize'); const basename = path.basename(__filename); // Before const env = process.env.NODE_ENV || 'development'; // After const env = process.env.NODE_ENV.trim() || 'development'; // add .trim() const config = require(__dirname + '/../config/config.js')[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); } ... db.sequelize = sequelize; db.Sequelize = Sequelize; module.exports = db;

更多详细信息

的package.json"scripts": { "db:migrate:dev": "sequelize db:migrate --env development", "db:migrate:test": "sequelize db:migrate --env test", "db:migrate:production": "sequelize db:migrate --env production", "db:reset": "sequelize db:migrate:undo", "start": "SET NODE_ENV=production && babel-watch server/server.js", "dev": "SET NODE_ENV=development && babel-watch server/server.js", "test": "SET NODE_ENV=testing && babel-watch server/server.js" }

[示例

，假设我通过输入终端启动服务器npm run dev If i do console.log(process.env.NODE_ENV) // output is "development " with a space. Hence, process.env.NODE_ENV === "development" // return false or "development " === "development" // return false
Javascript Trim（）从字符串的两侧删除空格
您想要更多资源？请访问w3c