How to sync models on server start using Next.js and sequelize?

Question

I'm used to using Express with React on the backend and working in a server.js file to sync the database. With Next.js, there's no server.js file to sync the models with sequelize. My work around right now is syncing the models upon user login/sign up (see code below), but I know this will cause a bunch of issues down the line. How do I setup my files and sync the models upon a Next.js server start up?

So far this is how I've set up my backend:

./src/pages/api/user/login.js

const { User } = require('../../../db/model');
const { signToken } = require('../../../auth/auth');
const sequelize = require('../../../db/config/connections');
sequelize.sync({ force: false }); //<----- This is where I sync all my models

export default async function handler(req, res) {
    if (req.method === 'POST') {
        try {
            const user = await User.findOne({
                where: {
                    username: req.body.username
                }
            });

            if (!user) {
                res.status(400).json({ message: 'Incorrect login credentials' })
                return
            }

            const password = await user.checkPassword(req.body.password)

            if (!password) {
                res.status(400).json({ message: 'Incorrect login credentials' })
                return
            }

            const token = signToken(user)
            res.status(200).json({ token, user })

        } catch (err) {
            console.log(err);
            res.status(400).json(err)
        }

    } else {
        res.status(400).json({ message: 'Invalid request' })
    }
}

./src/db/model/user.js

const { Model, DataTypes } = require("sequelize");
const sequelize = require("../config/connections");
const bcrypt = require("bcrypt");

class User extends Model {
    checkPassword(loginPassword) {
        return bcrypt.compareSync(loginPassword, this.password);
    }
}

User.init(
    {
        id: {
            type: DataTypes.INTEGER,
            allowNull: false,
            autoIncrement: true,
            primaryKey: true,
        },
        username: {
            type: DataTypes.STRING,
            allowNull: false,
            unique: true,
        },
        email: {
            type: DataTypes.STRING,
            allowNull: false,
            unique: {
                msg: "Email already in use!",
            },
            validate: {
                isEmail: {
                    msg: "Please enter a valid email address",
                },
            },
        },
        password: {
            type: DataTypes.STRING,
            allowNull: false,
            validate: {
                len: {
                    args: [8, 30],
                    msg: "Password must be between 8 and 30 characters",
                },
            },
        },
    },
    {
        hooks: {
            beforeCreate: async (newUser) => {
                newUser.password = await bcrypt.hash(newUser.password, 10);
                return newUser;
            },
            beforeUpdate: async (updateUser) => {
                if (updateUser.password) {
                    updateUser.password = await bcrypt.hash(updateUser.password, 10);
                }
                return updateUser;
            },
        },
        sequelize,
        timestamps: false,
        freezeTableName: true,
        underscored: true,
        modelName: "hungry_user",
    }
);

module.exports = User;

./src/db/config/connections.js

require("dotenv").config();
const Sequelize = require("sequelize");

const sequelize = process.env.JAWSDB_URL
    ? new Sequelize(process.env.JAWSDB_URL)
    : new Sequelize(
            process.env.DB_NAME,
            process.env.DB_USER,
            process.env.DB_PASSWORD,
            {
                host: "127.0.0.1",
                dialect: "mysql",
                port: 3306,
            }
      );

module.exports = sequelize;

The tables are able to sync, but I want them to sync upon starting the server.

Answer 1

I got the same issue

my workaround was to do every thing via CLI commands

In this order:

1- Run > npx sequelize-cli migration:generate --name first-setup to generate skeleton for first migration

2- Call dbConfig.sequelize.sync({ force: true }); inside up method

3- Run > npx sequelize-cli db:migrate

4- Run > npx sequelize-cli seed:generate --name first-seed to generate skeleton for first seed

5- Fill seeding script with your logic than

6- Run npx sequelize db:seed --seed [...seedName].js --debug

Note: for more details about Sequelize CLI migrations/seeding

Check out: https://sequelize.org/docs/v6/other-topics/migrations/