How to create new module

[vicky-gonsalves]

#60 (comment)

[vicky-gonsalves]

In the project structure, there are 5 basic directories,

1. controllers
2. routers
3. services
4. models
5. validations

---

1. controllers dir holds the controller of the module. For an example, to create new module named article, in controllers dir create new controller file named article.controller.ts and create new class named ArticleController

class ArticleController {
  public static async create(
    { request, response }: RouterContext<string>,
  ): Promise<void> {
    const body = request.body();
    ...
    ...
    response.status = Status.Created;
  }

}

2. routers dir holds the routes of the module. To create new route for POST article, create new file under routers dir named article.router.ts and add routes as per requirement. Check user.router.ts for reference.
   eg. To create new Article we would add new route :

router.post(
  '/api/articles',
  ArticleController.create,
);

if you want to protect the above route using auth, validation and permissions,
add the middleware :

router.post(
  '/api/articles',
  auth([PermissionList.MANAGE_ARTICLES]),   ---------> add this new permission in `config/roles.ts`
  validate(createUserValidation),                      ---------> create new validation under `validations` dir
  ArticleController.create,
);

Once done initialize this new router in router/index.ts file:

const init = (app: Application) => {
  app.use(authRouter.routes());
  app.use(userRouter.routes());
  app.use(defaultRouter.routes());  
  app.use(ArticleRouter.routes());   ---------------------> new router  
  ...
  app.use(ArticleRouter.allowedMethods());    ---------------------> new router  

3. services is the main heart of the module where all processing happens. We use Thin controller and Fat Services approach. To create a new service, add new service file article.service.ts under services dir.

class ArticleService {  
  public static async createArticle(
    options: CreateArticleStructure,
  ): Promise<string | Bson.ObjectId | Error> {
    // add your service logic
    }
    

4. models contains the database schema. So to create new schema for article, add new file article.model.ts under models dir.

5. Similarly you can add route specific validations in validations files.