4.1.1. Implement Brand Module

1. Create Module Directory#

Start by creating the directory src/modules/brand that will hold the Brand Module's files.

2. Create Data Model#

To create a data model that represents a new brand table in the database, create the file src/modules/brand/models/brand.ts with the following content:

src/modules/brand/models/brand.ts
1import { model } from "@medusajs/utils"2
3export const Brand = model.define("brand", {4  id: model.id().primaryKey(),5  name: model.text(),6})

This creates a Brand data model which has an id primary key property, and a name text property.

3. Create Module Service#

Next, you'll create the module's main service that manages the Brand data model.

Create the file src/modules/brand/service.ts with the following content:

src/modules/brand/service.ts
1import { MedusaService } from "@medusajs/utils"2import { Brand } from "./models/brand"3
4class BrandModuleService extends MedusaService({5  Brand,6}) {7
8}9
10export default BrandModuleService

The BrandModuleService extends a MedusaService function imported from @medusajs/utils which is a service factory.

The MedusaService function receives an object of the module's data models as a parameter, and generates methods to manage those data models, such as createBrands and updateBrands.

Those methods are now available at the BrandModuleService class and you'll use them in upcoming steps.

4. Create Module's Definition#

To export the module's definition, create the file src/modules/brand/index.ts with the following content:

src/modules/brand/index.ts
1import { Module } from "@medusajs/utils"2import BrandModuleService from "./service"3
4export const BRAND_MODULE = "brandModuleService"5
6export default Module(BRAND_MODULE, {7  service: BrandModuleService,8})

This exposes the module to your application and allows you to resolve the BrandModuleService, which is its main service.

5. Register Module in Config#

Finally, add the module to Medusa's configurations in medusa-config.js:

medusa-config.js
1module.exports = defineConfig({2  // ...3  modules: {4    brandModuleService: {5      resolve: "./modules/brand",6    },7  },8})

6. Generate and Run Migrations#

To reflect the data model in the database, generate migrations for the brandModuleService module and migrate the changes to the database:

Terminal
❯npx medusa db:generate brandModuleService❯npx medusa db:migrate

Next Step: Create Brand Workflow#

In the next step, you'll create a workflow whose steps use the Brand Module's main service to create a brand.