php - CakePHP Controller beforeFilter custom validation to prevent save data into DB

I have a Controller and a few functions inside. Some function are basically save data into DB. One of the function require a filter that specific type of user can't do write access into DB.

My question is how do I block to save data into db for specific user role.

class TestController extends AppController {
     public function beforeFilter(){
        if(in_array($this->action, ['f1','f2'])) {
             if($this->authenticatedUser['role'] == 'readonly') {
                //return message
                //block save data into db
             }
         }
     }

     public function f1() {
        //save data into db
     }

     public function f2() {
        //save data into db
     }

     public function f3() {
     }
}

When I tried to write using f1 or f2, it goes to beforeFilter and show the message as well but data save into db also. How should I block it while I tried to write data into db on beforeFilter.

Solution:

Here is some logic:

• check if the request is a post

• check which method is requested

• if both checks match, create a flash message and make a GET redirect to the desired method

  if($this->request->is('post') && in_array($this->action, ['f1','f2'])) {
      if($this->authenticatedUser['role'] == 'readonly') {
           //set flash message
           //get redirect to action
      }
  }
  

Next

function f1() {
   // if request is post, save data
   // else return find data or empty object / array
}