Refactoring Controllers (Route Handlers)

Hi all,In the context of nodejs backend API applications, is it accurate to say that controllers(route handlers) have the following responsibilities (and nothing more):Extract the parameters (query or body) from the requestCall external functions to perform backend operationsReturn an HTTP response (with status code and serialized data)In the past, I have (admittedly with lack of foresight), done something of the following nature:function createUserController(req, res, next) { const userName = req.body.name // perform CRUD operations with an ORM User.create(userName) .then(function() { res.status(200).end(); }) .catch(function() { res.status(400).end(); }) } Aside from a bloated controller, I end up having express related objects passed down to data layers (as stipulated here: https://github.com/i0natan/nodebestpractices#-12-layer-your-components-keep-express-within-its-boundaries), which also makes it more difficult to unit test.To remedy this issue, what do you think of the following implementation:// Controller function createUserController(req, res, next) { const userName = req.body.name // perform CRUD operations with an ORM userDataOperations = new UserDataOperations(); userDataOperations .on('SUCCESS', function() { res.status(200).end() }) .on('ERROR', function() { res.status(400).end() }) userDataOperations.saveUser(userName); } // CRUD operations class UserDataOperations extends EventEmitter { saveUser(userName) { User.create(userName) .then(function() { this.emit('SUCCESS') }) .catch(function() { this.emit('ERROR') }) } } Have you guys experienced any issues with an EventEmitter implementation? How would you generally approach this?

Submitted January 18, 2019 at 10:06PM by raccoonranger73