Grails 5 controller outside grails-app/controllers only works after restart (404 on cold start)

[luizmattoz]

Problem
I have a controller at:
grails-app/clima/infraestrutura/adaptadores/entrada/controllers/TipoColetaController.groovy
It returns 404 on a fresh application start. If I save the file (Ctrl+S) — which triggers a recompile + automatic DevTools restart — it starts working normally, until the next time I restart the application from scratch (then it breaks again).

What I've already tried (no luck)

1. Removed Spring's @controller (org.springframework.stereotype.Controller) that was on the class — didn't fix it.
2. Manually implemented the grails.artefact.Controller trait — didn't fix it.
3. Annotated the class with @ArteFact("Controller") — didn't fix it.

Current code:
`package clima.infraestrutura.adaptadores.entrada.controllers

import grails.artefact.Artefact

@ArteFact("Controller")
class TipoColetaController {
static allowedMethods = [save: "POST", update: "POST", delete: "POST"]
// ...
}`

Questions

1. Why does recompiling/restarting fix it, if the folder structure doesn't change?
2. Is there a known race condition between Grails' artefact scanning and the DevTools restart?
3. What's the correct way to have controllers outside grails-app/controllers/ work consistently in Grails 5, without depending on a restart?

[sbglasius]

Your controller should be in grails-app/controllers/clima/... to become a controller. Why it works when re-compiling is a bit of a mystery.. The controller do not need any annotations to work, when placed in grails-app/controllers/clima/...

[luizmattoz]

First of all, thank you for your answer!

Our company has a legacy project in Grails, so the code base is a quite messy. We're working on splitting it into modules to improve the organization and, eventually, make it easier to migrate into microservices. Because of that, having better control over bean discovery is very important for us.

Over the weekend, I managed to achive what I needed by organizing the project like this

grails-app
└── modules
    ├── package1
    │   └── ...
    └── package2
        └── ...
    └── package3
        └── ...

With packages such as:

package package1.core.entity
package package1.infra.controler
package package2.core.entity
package package2.infra.controler
...

Controller are anoted with org.springframework.stereotype.Controller, and domain classes with grails.gorm.annotation.Entity.

So this structure ended up solving my problem.

Thanks again taking time for help!