Sequelize Issue By Separating Model Logic from Model Configuration

问题:

I am following the sequelize best practices by connecting to a host and importing all models into one file and then calling that file when interacting the model. For some reason it looks like this is causing an issue as I am getting an error at using the define method for the sequelize variable and I ran a test with a file that contained both logic together and I was able to add a user.

Error:

TypeError: Cannot read property 'define' of undefined     at new module.exports (/Users/user/Desktop/Projects/node/ann/app/models/ann-model.js:3:27)     at /Users/user/Desktop/Projects/node/ann/app/controllers/appRoutes.js:13:20 

Here is my file that contains the connection to the database (dbIndex.js):

var Sequelize = require('sequelize'); var sequelize = new Sequelize('dbname', 'user', 'pwd', {     host:'localhost',     port:'3306',     dialect: 'mysql' });  sequelize         .authenticate()         .then(function(err) {             if (!!err) {                 console.log('Unable to connect to the database:', err)             } else {                 console.log('Connection has been established successfully.')             }         });  var db = {}  db.Ann = sequelize.import(__dirname + "/ann-model");  db.sequelize = sequelize; db.Sequelize = Sequelize;  module.exports = db; 

Here is the Model file (ann-model.js):

module.exports = function(sequelize, DataTypes) {  var Ann = sequelize.define('ann', {     ann_id: {         type: DataTypes.INTEGER,         primaryKey: true     },     ann_date: DataTypes.DATE, }, {     freezeTableName: true });     return Ann; } 

Here is where I'm calling the model with a POST method.

(appRoutes.js):

var express = require('express'); var appRoutes   = express.Router(); var Annotation = require('../models/ann-model');  appRoutes.route('/')       .get(function(req, res){         res.render('pages/activity-feed.hbs');     })      .post(function(req, res){          var ann = new Ann();          ann.ann_date = req.body.ann-date;           annotation.save(function(err){             if (err)                 res.send(err);         });     });  module.exports = appRoutes; 

Test file combining logic and modeling in one file:

var Sequelize = require('sequelize'); var sequelize = new Sequelize('dbname', 'user', 'pwd', {     host:'localhost',     port:'3306',     dialect: 'mysql' });   var Ann = sequelize.define('ann', {     ann_id: {         type: Sequelize.INTEGER,         primaryKey: true     },     ann_date: Sequelize.DATE, }, {     freezeTableName: true });  sequelize.sync().then(function(){     return Ann.create({         ann_id: 3,         discovery: 'This is a test.'     }); }).then(function(tation) {     console.log(tation.get({         plain: true     })); }); 

回答1:

I think problem in your post method, but structure is really confusing so can you do this

models/index.js

"use strict";  var fs        = require("fs"); var path      = require("path"); var Sequelize = require("sequelize"); var env       = process.env.NODE_ENV || "development"; var config    = require(__dirname + '/../config/config.json')[env]; var sequelize = new Sequelize(config.database, config.username, config.password, config); var db        = {};  fs   .readdirSync(__dirname)   .filter(function(file) {     return (file.indexOf(".") !== 0) && (file !== "index.js");   })   .forEach(function(file) {     var model = sequelize.import(path.join(__dirname, file));     db[model.name] = model;   });  Object.keys(db).forEach(function(modelName) {   if ("associate" in db[modelName]) {     db[modelName].associate(db);   } }); db.sequelize = sequelize; db.Sequelize = Sequelize;  module.exports = db; 

models/ann-model.js

"use strict";  module.exports = function(sequelize, DataTypes) {  var Ann = sequelize.define('ann', {     ann_id: {         type: DataTypes.INTEGER,         primaryKey: true     },     ann_date: DataTypes.DATE, }, {     freezeTableName: true });     return Ann; } 

routes/index.js

var express = require('express'); var appRoutes   = express.Router(); var models = require('../models');  appRoutes.route('/')       .get(function(req, res){         res.send('ok');     })      .post(function(req, res){        models.ann       .build({ ann_id: 55, ann_date: new Date() })       .save()       .then(function(anotherTask) {         res.send("POST OK");        }).catch(function(error) {         res.send(error);       })      });  module.exports = appRoutes; 

文章来源: Sequelize Issue By Separating Model Logic from Model Configuration