Sequelize Association Error: A is not associated to B - node.js

Question

I'm using Sequelize for my Postgres database. I have a Messages and a Users table; a user has many messages and a message belongs to a user. I've defined my models as follows:
User
module.exports = (sequelize, DataTypes) => {
const User = sequelize.define('User', {
firstName: {
type: DataTypes.STRING,
allowNull: false
},
lastName: {
type: DataTypes.STRING,
allowNull: false
},
email: {
type: DataTypes.STRING,
allowNull: false,
unique: true,
validate: {
isEmail: true,
}
},
password: {
type: DataTypes.STRING,
allowNull: false,
validate: {
len: [8, 50],
}
},
}, {
modelName: 'User',
});
User.associate = (models) => {
User.hasMany(models.Message, { foreignKey: 'userId', as: 'Messages' })
}
return User;
};
Message
module.exports = (sequelize, DataTypes) => {
const Message = sequelize.define('Message', {
content: {
allowNull: false,
type: DataTypes.STRING,
validate: {
len: [1, 248],
}
},
userId: {
type: DataTypes.INTEGER,
allowNull: false,
references: {
model: 'Users',
key: 'id'
}
},
likes: {
defaultValue: 0,
type: DataTypes.INTEGER
},
}, {
modelName: 'Message',
});
Message.associate = (models) => {
Message.belongsTo(models.User, { foreignKey: 'userId', as: 'User', onDelete: 'CASCADE' })
}
return Message;
};
And here's how I'm testing them:
User.create({
firstName: 'Test', lastName: 'Test', email: 'test#test.com', password: '87654321'
}).then((newUser) => {
console.log(newUser.get())
})
Message.bulkCreate([
{ content: "Hello", likes: 0, userId: 1 },
{ content: "Hello World", likes: 0, userId: 1 },
{ content: "Hello World 2", likes: 123, userId: 1 }
])
.then((newMessages) => {
console.log(newMessages)
})
const findAllWithMessages = async () => {
const users = await User.findAll({
include: [{
model: Message
}]
});
console.log(JSON.stringify(users, null));
}
Here's my Migration file to create the users table:
module.exports = {
up: async (queryInterface, Sequelize) => {
await queryInterface.createTable('Users', {
id: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: Sequelize.INTEGER
},
firstName: {
type: Sequelize.STRING,
allowNull: false
},
lastName: {
type: Sequelize.STRING,
allowNull: false
},
email: {
type: Sequelize.STRING,
allowNull: false,
unique: true,
validate: {
isEmail: true,
}
},
password: {
type: Sequelize.STRING,
allowNull: false,
validate: {
len: [8, 50],
}
},
createdAt: {
allowNull: false,
type: Sequelize.DATE
},
updatedAt: {
allowNull: false,
type: Sequelize.DATE
}
});
},
down: async (queryInterface, Sequelize) => {
await queryInterface.dropTable('Users');
}
};
And the messages table:
'use strict';
module.exports = {
up: async (queryInterface, Sequelize) => {
await queryInterface.createTable('Messages', {
id: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: Sequelize.INTEGER
},
userId: {
type: Sequelize.INTEGER,
allowNull: false,
references: {
model: 'Users',
key: 'id',
as: 'userId',
},
onUpdate: 'CASCADE',
onDelete: 'SET NULL',
},
content: {
allowNull: false,
type: Sequelize.STRING,
validate: {
len: [1, 248],
}
},
likes: {
defaultValue: 0,
type: Sequelize.INTEGER
},
createdAt: {
allowNull: false,
type: Sequelize.DATE
},
updatedAt: {
allowNull: false,
type: Sequelize.DATE
}
});
},
down: async (queryInterface, Sequelize) => {
await queryInterface.dropTable('Messages');
}
};
I'm registering my models and associations using Sequelize CLI out of the box code when you run sequelize-cli init:
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.json')[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 => {
return (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);
}
});
const User = require('./user')(sequelize, Sequelize.DataTypes)
const Message = require('./message')(sequelize, Sequelize.DataTypes)
db.models = { User, Message }
db.sequelize = sequelize;
db.Sequelize = Sequelize;
db.DataTypes = Sequelize.DataTypes
module.exports = db;
Finally, when I run findAllWithMessages(), I'm getting this error UnhandledPromiseRejectionWarning: SequelizeEagerLoadingError: Message is not associated to User!
I can confirm that the models are being created and that the association between the models work because when I run a raw SQL query select * from "Messages" as a inner join "Users" as b on b.id = a."userId" where a."userId"=1; I get the correct results. So I'm assuming its a Sequelize thing.
Any help is appreciated!

Answer 1

I've found my issue. In the code I was importing from db.models = { User, Message } so this block Object.keys(db).forEach(modelName)... wasn't associating the models I was using. Essentially, I was calling the .associate function on instances of the models that were different than the instances I was using.