[FEATURE] new rest api

__Tasks:__
- [x] refactor all controllers to new api
- [ ] gather feedback for my changes 

__Informations:__

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| Tests pass?   | none
| Fixed tickets | [none]
| Doc           | none
@marcelmoosbrugger I think we have already talked about removing these functions, didn't we?