factory.js

// file: models/factory.js
"use strict";

module.exports = (sequelize, DataTypes) => {

    const Factory = sequelize.define("factory", {
        uuid: {
            type: DataTypes.UUID,
            defaultValue: DataTypes.UUIDV4,
            allowNull: false,
            unique: true,
            primaryKey: true
        },
        google_id: {
            type: DataTypes.STRING
        },
        price_id: {
            type: DataTypes.INTEGER,
        },
        name: {
            type: DataTypes.STRING,
            unique: true
        }
    });

    Factory.associate = function (models) {
        Factory.hasOne(models.prices, {foreignKey: "id", sourceKey: "price_id"});
        Factory.hasMany(models.bills, {foreignKey: "factory_id", sourceKey: "uuid"});
        Factory.hasMany(models.acts, {foreignKey: "factory_id", sourceKey: "uuid"});
        Factory.hasMany(models.user, {foreignKey: "factory_id", sourceKey: "uuid"});
        Factory.hasMany(models.ribbon, {foreignKey: "factory_id", sourceKey: "uuid"});
        Factory.hasMany(models.cable, {foreignKey: "factory_id", sourceKey: "uuid"});
    };
    return Factory;
};

sequelize.js

// file: middlewares/sequelize.js
"use strict";

const Sequelize = require("sequelize");
const fs = require("fs");
const path = require("path");

module.exports = function SequelizeDbMiddleware(options = {}) {

    options = {
        dialect: "postgres",
        define: {
            timestamps: false
        },
        logging: console.log,
        pool: {
            max: 5,
            min: 1,
            acquire: 6000,
            idle: 3000,
            log: true
        },
        ...options
    };
    const connection = new Sequelize(process.env.DB, options);
    const models = {};

    return {
        name: "Sequelize",

        async starting() {

            await connection.connectionManager.getConnection();

            this.logger.info("Sequelize middleware ready");
            const dir = __dirname + "/../models";

            fs
            .readdirSync(dir)
            .filter(file => file.endsWith(".js"))
            .map(file => {
                const model = require(path.join(dir, file))(connection, Sequelize.DataTypes);
                models[model.name] = model;
                return model;
            }).forEach(model => {
                if ("associate" in model) model.associate(models);
            });

            this.logger.info("Sequelize all models loaded!");
            this.connection = connection;

        },

        async stopping() {
            if (connection) await connection.close();
            this.logger.info("CockroachDB middleware close");
        },

        serviceCreating(service, schema) {
            if (!schema.name.startsWith("$")) {
                service.crdb = connection;
                service.crdb.Op = Sequelize.Op;
                service.models = models;
                service.Sequelize = Sequelize;
                this.logger.debug("Sequelize models for `" + schema.name + "` ready");
            }
        }
    };
};