Develop Reference

How to find several fields of a foreign key in a join table in Node.js Sequelize

I have a Node.js application with Express, Sequelize as ORM and PostgreSQL for the database. In this app I have candidate model and mission model as below.
'use strict';
const {
Model
} = require('sequelize');
module.exports = (sequelize, DataTypes) => {
class candidat extends Model {
static associate(models) {
this.belongsToMany(models.mission, {
through: "candidat_mission",
foreignKey: "candidatId",
otherKey: "idMission",
});
}
}
candidat.init({
candidatId: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: DataTypes.INTEGER
},
lastName: {
type: DataTypes.STRING,
allowNull: false,
},
firstName: {
type: DataTypes.STRING,
allowNull: false,
},
email: {
isEmail: true,
allowNull: false,
type: DataTypes.STRING,
unique: true,
},
}, {
sequelize,
modelName: 'candidat',
tableName: 'candidat',
freezeTableName: true,
});
return candidat;
};
'use strict';
const {
Model
} = require('sequelize');
module.exports = (sequelize, DataTypes) => {
class mission extends Model {
static associate(models) {
this.belongsToMany(models.candidat, {
through: "candidat_mission",
foreignKey: "idMission",
otherKey: "candidatId",
})
}
}
mission.init({
idMission: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: DataTypes.INTEGER
},
title: {
type: DataTypes.STRING,
allowNull: false
},
aliasTitle: {
type: DataTypes.STRING,
allowNull: true
},
description: {
type: DataTypes.TEXT,
allowNull: true
}
}, {
sequelize,
modelName: 'mission',
tableName: 'mission',
freezeTableName: true,
});
return mission;
};
These two models are linked in many-to-many by a candidate_mission join table. In this model, I added fields like a foreign key which points to another table, that of users.
'use strict';
const {
Model
} = require('sequelize');
module.exports = (sequelize, DataTypes) => {
class candidat_mission extends Model {
static associate(models) {
this.belongsTo(models.user, { foreignKey: "fk_user" });
}
}
candidat_mission.init({
candidatMissionId: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: DataTypes.INTEGER
},
candidatId: {
type: DataTypes.INTEGER,
allowNull: false,
references: {
model: { tableName: 'candidat' },
key: "candidatId",
},
},
idMission: {
type: DataTypes.INTEGER,
allowNull: false,
references: {
model: { tableName: 'mission' },
key: "idMission",
},
},
fk_user: {
type: DataTypes.INTEGER,
allowNull: true,
references: {
model: { tableName: 'user' },
key: "userId",
},
},
}, {
sequelize,
modelName: 'candidat_mission',
tableName: 'candidat_mission',
timestamps: true,
freezeTableName: true,
});
return candidat_mission;
};
When I make a "GET" request, I do have the information from the candidate_mission table (if a candidate is linked to this mission), but for the user it only returns the ID and I would like it to return all the fields present in the Users model, what can I do?
Here, my function in the mission controller which allows to add a candidate to this mission :
const addCandidats = async (req, res) => {
try {
const mission = await Mission.findByPk(req.body.idMission);
if (mission) {
const candidat = await Candidat.findByPk(req.body.candidatId);
if (candidat) {
mission.addCandidat(candidat,
{through: {
fk_user: req.body.fk_user && req.body.fk_user
}});
return res.status(200).send(mission);
} else {
console.log("Candidat non trouvé");
return null;
}
} else {
console.log("Mission non trouvée!")
return null;
}
} catch (error) {
console.log(error);
}
};
Currently, my query returns me this :
"candidat_mission":
{
"candidatMissionId": 2,
"candidatId": 1,
"idMission": 7,
"fk_user": 1,
"createdAt": "2023-02-14T10:34:08.302Z",
"updatedAt": "2023-02-14T15:06:10.232Z"
},
And i want it to come back to me :
"candidat_mission":
{
"candidatMissionId": 2,
"candidatId": 1,
"idMission": 7,
"fk_user": {
"userId": 1,
"email": "blabla#gmail.com",
"name": "blabla"
},
"createdAt": "2023-02-14T10:34:08.302Z",
"updatedAt": "2023-02-14T15:06:10.232Z"
},

After associating 2 models, we have to query again to get the object along with the relationship.
await mission.addCandidat(candidat,
{through: {
fk_user: req.body.fk_user && req.body.fk_user
}});
const result = await CandidatMission.findOne({
where: { candidatId: req.body.candidatId, idMission: req.body.idMission },
include: models.user,
})
return res.status(200).send(result);

How to do a query in Sequelize?

I've an existing Postgres database. Throught sequelize-auto, I generated the models for the existing database. For example, let's look at the tc_devices table (tc_devices.js):
const Sequelize = require('sequelize');
module.exports = function(sequelize, DataTypes) {
return sequelize.define('tc_devices', {
id: {
autoIncrement: true,
autoIncrementIdentity: true,
type: DataTypes.INTEGER,
allowNull: false,
primaryKey: true
},
name: {
type: DataTypes.STRING(128),
allowNull: false
},
uniqueid: {
type: DataTypes.STRING(128),
allowNull: false,
unique: "tc_devices_uniqueid_key"
},
lastupdate: {
type: DataTypes.DATE,
allowNull: true
},
positionid: {
type: DataTypes.INTEGER,
allowNull: true
},
groupid: {
type: DataTypes.INTEGER,
allowNull: true,
references: {
model: 'tc_groups',
key: 'id'
}
},
attributes: {
type: DataTypes.STRING(4000),
allowNull: true
},
phone: {
type: DataTypes.STRING(128),
allowNull: true
},
model: {
type: DataTypes.STRING(128),
allowNull: true
},
contact: {
type: DataTypes.STRING(512),
allowNull: true
},
category: {
type: DataTypes.STRING(128),
allowNull: true
},
disabled: {
type: DataTypes.BOOLEAN,
allowNull: true,
defaultValue: false
}
}, {
sequelize,
tableName: 'tc_devices',
schema: 'public',
timestamps: false,
indexes: [
{
name: "tc_devices_pkey",
unique: true,
fields: [
{ name: "id" },
]
},
{
name: "tc_devices_uniqueid_key",
unique: true,
fields: [
{ name: "uniqueid" },
]
},
]
});
};
In database.js, I connect to the database:
const { Sequelize } = require('sequelize');
const sequelize = new Sequelize(database, user, password, {
host,
port,
dialect: 'postgres',
logging: false
})
async function db_connection(){
try{
await sequelize.authenticate();
console.log('Connection has been estabilished successfully.');
}catch{
console.log('Unable to connect to the database.');
}
}
db_connection()
How can I do a simple query on the tc_devices table? what should I import in database.js? in tc_devices I export function(sequelize, DataTypes)... but I can't understand how to do a query in database.js with this function...could you help me? thank you so much.

You need to register all models and their associations before executing the first query with these models. Look at my answer here.
As soon as you do it you can execute queries like this:
// assuming db already stores all model definitions
const allRecords = await db.tcDevices.findAll({})

Node JS API Sequelize PostgreSQL UUID as primary key return error "column Nan does not exist"

I'm working on a REST API for the backend of a simple e-commerce app using Node JS, PostgreSQL and Sequelize, and I'm facing an issue with Sequelize when I try to add a product to the shopping cart. It returns an error "column Nan does not exist"
Initially I was using Integer for the user Id as the primary key, then I changed for UUID to better suit the purpose.
The code I'm using for the models and migrations is the following:
//User model
export default (sequelize, DataTypes) => {
const User = sequelize.define(
'User',
{
id: {
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4,
allowNull: false,
primaryKey: true,
unique: true,
},
name: {
type: DataTypes.STRING,
allowNull: false
},
password: {
type: DataTypes.STRING,
allowNull: false
},
email: {
type: DataTypes.STRING,
allowNull: false,
unique: {
name: 'user_email',
msg: 'A user with this email already exists.'
}
},
},
User.associate = models => {
User.hasOne(models.Cart, {
foreignKey: 'userId',
as: 'cart',
onDelete: 'cascade'
});
};
User.associate = models => {
User.hasMany(models.Order, {
foreignKey: 'userId',
as: 'orders',
onDelete: 'cascade'
});
};
return User;
};
//User migration
export const up = (queryInterface, Sequelize) =>
queryInterface.createTable('Users', {
id: {
type: Sequelize.UUID,
defaultValue: Sequelize.UUIDV4,
allowNull: false,
primaryKey: true,
unique: true,
},
name: {
allowNull: false,
type: Sequelize.STRING
},
password: Sequelize.STRING,
email: {
allowNull: false,
type: Sequelize.STRING,
unique: true
},
createdAt: {
allowNull: false,
type: Sequelize.DATE,
defaultValue: Sequelize.fn('now')
},
updatedAt: {
allowNull: false,
type: Sequelize.DATE,
defaultValue: Sequelize.fn('now')
},
});
export const down = queryInterface => queryInterface.dropTable('Users');
Cart model
export default (sequelize, DataTypes) => {
const Cart = sequelize.define('Cart', {
id: {
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4,
allowNull: false,
primaryKey: true,
},
userId: {
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4,
allowNull: false
},
cartItem: {
type: DataTypes.TEXT,
allowNull: false,
get(value) {
return JSON.parse(this.getDataValue(value));
},
set(value) {
this.setDataValue('cartItem', JSON.stringify(value));
}
}
});
Cart.associate = models => {
Cart.belongsTo(models.User, {
foreignKey: 'userId',
as: 'owner'
});
};
return Cart;
};
Cart migration
export const up = (queryInterface, Sequelize) =>
queryInterface.createTable('Carts', {
id: {
allowNull: false,
primaryKey: true,
type: Sequelize.UUID,
defaultValue: Sequelize.UUIDV4,
},
userId: {
type: Sequelize.UUID,
defaultValue: Sequelize.UUIDV4,
allowNull: false
},
cartItem: {
type: Sequelize.TEXT,
allowNull: false
},
createdAt: {
allowNull: false,
type: Sequelize.DATE,
defaultValue: Sequelize.fn('now')
},
updatedAt: {
allowNull: false,
type: Sequelize.DATE,
defaultValue: Sequelize.fn('now')
}
});
export const down = queryInterface => queryInterface.dropTable('Carts');
Code to handle the add to cart:
addToCart() {
return this.asyncWrapper(async (req, res) => {
const { body, user } = req;
body.userId = user.id;
const cart = await this.service.addToCart(body);
this.sendResponse(res, cart, undefined, 201);
});
}
Add to cart service
async cart(userId, options = {}) {
const cart = await super.find({ userId }, options);
return cart;
}
async addToCart(data, options) {
const { userId, productId, qty } = data;
const [result] = await this.model.findOrCreate({
where: { userId: +userId },
defaults: { cartItem: new CartItem() }
});
const cartData = JSON.parse(result.dataValues.cartItem);
const cartItem = new CartItem(cartData);
const product = await ProductService.getById(productId, { plain: true });
ExceptionHandler.throwErrorIfNull(product);
const cart = cartItem.addToCart(product, qty);
result.cartItem = cart;
result.save();
return result;
}
The SQL query generated by Sequelize is the following:
SELECT "id","userId","cartItem","createdAt","updatedAt" FROM "Carts" AS "Cart" WHERE "Cart"."userId" = NaN LIMIT 1;
The goal is to use UUID as primary key in the database.
This issue started when I changed the Datatype from Integer for UUID and I can't see what is wrong with the code.
Any advice on how to solve this?
Sequelize version: "^5.21.9" with "pg": "^8.2.0" and "pg-hstore": "^2.3.3".

If you switched a data type from INTEGER to UUID you shouldn't try to convert UUID-string to a number doing where: { userId: +userId }.
Pass userId as is:
where: { userId }

Sequelize assocation to same table

I have a table called documents that has a column called parentId which is a reference to another document record.
With my current code i'm getting the error
insert or update on table "documents" violates foreign key constraint "documents_parentId_fkey"
documents migration
'use strict'
module.exports = {
up: (queryInterface, Sequelize) => {
return queryInterface.createTable('documents', {
id: {
allowNull: false,
primaryKey: true,
type: Sequelize.UUID,
defaultValue: Sequelize.UUIDV4
},
parentId: {
allowNull: true,
type: Sequelize.UUID,
references: {
model: 'documents',
key: 'id'
}
},
createdAt: {
allowNull: false,
type: Sequelize.DATE
},
lastUpdatedAt: {
allowNull: false,
type: Sequelize.DATE
},
lastUpdatedBy: {
allowNull: false,
type: Sequelize.UUID
}
})
},
down: (queryInterface, Sequelize) => {
return queryInterface.dropTable('documents')
}
}
document model
'use strict'
module.exports = (sequelize, DataTypes) => {
const document = sequelize.define('document', {
id: {
allowNull: false,
primaryKey: true,
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4
},
parentId: {
allowNull: true,
type: DataTypes.UUID,
references: {
model: 'documents',
key: 'id'
}
},
lastUpdatedBy: {
allowNull: false,
type: DataTypes.UUID
}
},
{
updatedAt: 'lastUpdatedAt'
})
document.associate = function (models) {
document.belongsTo(models.document, { foreignKey: 'parentId' })
}
return document
}
How do you properly do associations to the same table?

I have a self referencing table configured with the constraints: false setting.
MyModel.belongsTo(MyModel, {
as: 'parentMyModel',
foreignKey: 'parentId',
constraints: false,
});

Looks like the constraint is valid (and a good one). My payload that I was submitting had a parent uuid which didn't actually reference any document with that id.
So my code was right, the data I was submitting was wrong.

Aggregate error when trying to use many to many table with sequelize

I'm getting this error:
AggregateError: aggregate error
at Promise.try.then
...
when trying to setup a many to many table in sequelize with this code:
let _document
db.document.create(payload, { include: ['documentAttributes', 'documentChildren'] })
.then(document => {
_document = document
const promises = []
// Add tags if there are any
if (req.body.tags) {
req.body.tags.forEach(tag => {
promises.push(db.tag.findOrCreate({ where: { key: tag.key } }))
})
}
return Promise.all(promises)
})
.then(tags => {
if (tags.length > 0) {
const allTags = tags.map(tag => tag[0])
return _document.setTags(allTags) // THIS LINE CAUSES THE ISSUE
}
document.js model:
'use strict'
module.exports = (sequelize, DataTypes) => {
const document = sequelize.define('document', {
id: {
allowNull: false,
primaryKey: true,
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4
},
...
lastUpdatedBy: {
allowNull: false,
type: DataTypes.UUID
}
},
{
updatedAt: 'lastUpdatedAt'
})
document.associate = function (models) {
document.hasMany(models.documentAttribute)
document.hasMany(models.documentChildren)
document.belongsToMany(models.tag, { through: 'documentTags' })
}
return document
}
tag.js model:
'use strict'
module.exports = (sequelize, DataTypes) => {
const tag = sequelize.define('tag', {
id: {
allowNull: false,
primaryKey: true,
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4
},
key: {
allowNull: false,
type: DataTypes.STRING
},
value: {
allowNull: false,
type: DataTypes.STRING
},
lastUpdatedBy: {
allowNull: false,
type: DataTypes.UUID
}
},
{
updatedAt: 'lastUpdatedAt'
})
tag.associate = function (models) {
tag.belongsToMany(models.document, { through: 'documentTags' })
}
return tag
}
documenttags.js model:
'use strict'
module.exports = (sequelize, DataTypes) => {
const documentTags = sequelize.define('documentTags', {
id: {
allowNull: false,
primaryKey: true,
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4
},
documentId: {
allowNull: false,
type: DataTypes.UUID
},
tagId: {
allowNull: false,
type: DataTypes.UUID
},
lastUpdatedBy: {
allowNull: false,
type: DataTypes.UUID
}
},
{
updatedAt: 'lastUpdatedAt'
})
documentTags.associate = function (models) {
// associations can be defined here
}
return documentTags
}

After reviewing the docs and discussing in the chat. The through property is necessary to set extra properties on the many-to-many table.
http://docs.sequelizejs.com/class/lib/associations/belongs-to-many.js~BelongsToMany.html
return _document.setTags(allTags, { through: { lastUpdatedBy: tag.lastUpdatedBy }})