我是 Web 开发的初学者,正在尝试使用 Mysql、Node.js 和 Express 创建一个项目。使用 Sequalize 时遇到此 TypeError 问题。有人可以向我解释一下并帮助我找到解决方案吗?
“续集”:“^6.19.0”
“sequelize-cli”:“^6.4.1”
/models/user.js:
module.exports = (sequelize, DataTypes) => {
const user = sequelize.define('User', {
name: DataTypes.STRING,
username: DataTypes.STRING,
email: DataTypes.STRING,
password: DataTypes.STRING,
});
return user;
};
/models/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];
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) => {
const model = require(path.join(__dirname, file))(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;
module.exports = db;
错误:
[nodemon] starting `node ./src/api/server.js`
/home/back-end/src/models/index.js:25
const model = require(path.join(__dirname, file))(sequelize, Sequelize.DataTypes);
^
TypeError: require(...) is not a function
at /home/back-end/src/models/index.js:25:54
at Array.forEach (<anonymous>)
at Object.<anonymous> (/home/back-end/src/models/index.js:24:4)
at Module._compile (internal/modules/cjs/loader.js:1068:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1097:10)
at Module.load (internal/modules/cjs/loader.js:933:32)
at Function.Module._load (internal/modules/cjs/loader.js:774:14)
at Module.require (internal/modules/cjs/loader.js:957:19)
at require (internal/modules/cjs/helpers.js:88:18)
at Object.<anonymous> (/home/back-end/src/services/usersService.js:1:18)
[nodemon] app crashed - waiting for file changes before starting...
根据经验,我在“models”目录中添加了一个不是模型的文件后遇到了这个问题。据说只能将模型文件添加到“models”目录中,因为index.js会检查整个目录中的每个文件。
正如@farajael 提到的,
/models
目录中的一个文件没有正确定义模型。例如,此目录中完全注释掉的文件将导致出现此错误。
您可以通过在
forEach loop
中添加 console.log 来调试导致问题的文件:
.forEach(file => {
console.log("FILE IS ",file);
model = require(path.join(__dirname, file))(sequelize, Sequelize.DataTypes);
然后重新启动你的服务器,查看服务器日志,崩溃前最后一条“FILE IS”语句就是问题所在。
其实我已经被这个问题困扰了一段时间了。对我有用的是,我使用称为(Sequelize 文档中的扩展模型)的 ES6 类来创建我的表,而不是(Sequelize.define)。老实说,我仍然不确定为什么,但您可以在 Sequelize 文档中找到如何使用扩展模型在 Sequelize 中创建表。
在你的index.js文件中,你应该只使用这种格式,它将解决你的错误
const fs = require('fs')
const path = require('path')
const Sequelize = require('sequelize')
const config = require('../config/config')
const db = {}
const sequelize = new Sequelize(
config.database,
config.username,
config.password,
config
);
fs
.readFileSync(__dirname)
.filter((file) =>
file !== 'index.js'
)
.forEach((file) => {
const model = require(path.join(__dirname, file))(sequelize,Sequelize.DataTypes)
db[model.name] = model
})
db.sequelize = sequelize
db.Sequelize = Sequelize
module.exports = db