Question

I am new to Grails. I have noticed that most tutorials show queries being created and stored in the Controller. It seems like this could really bloat the controller over time, especially as queries grow in greater number and complexity.

In my research, I read that controllers should stay as lean as possible (having to do with requesting and submitting data to/from the model/view, and that heavy querying is discouraged.

How have you gone about creating, storing, and calling queries for your Grails application?

Answer 1

There’s a good article about Grails best practices here. According to the post:

Don’t allow the controller to take over another role. The role of a
controller is to accept incoming requests, check permissions etc, ask
a domain or a service for a result, give the result back to the
requester in the desired format such as HTML, JSON, or XML. Keep the
controller as thin as possible. Don’t perform business logic, queries,
or updates within controllers.

So if you have a more complex logic, I suggest you to build services:

A service is the right candidate for complex business logic or coarse
grained code. If required, the service API can easily be exposed as a
RESTful/SOAP web service.