Conditional form validation in CakePHP 3 - php

Question

I want to validate some fields from validationDefault() function not all because of conditions but did not find any solution.
Example:
public function validationDefault(Validator $validator) {
$validator
->requirePresence('title', 'create')
->notEmpty('title');
$validator
->requirePresence('inquiry')
->allowEmpty('inquiry');
$validator
->requirePresence('dosage')
->allowEmpty('dosage');
$validator
->requirePresence('dosage_occurance')
->integer('dosage_occurance')
->allowEmpty('dosage_occurance');
return $validator;
}
Note: Response coming from two diffrent form first contains(title and inquiry) other contains(title, dosage and dosage_occurance).
I want to validate it from validationDefault() but it give me error
"dosage_occurance": {
"_required": "This field is required"
}
when I am not sending dosage_occurance which is correct but according to condition it is wrong.
using fieldList while creating new entity but it is not working.
Thanks

Answer 1

You want conditional validation.
Taken from the documentation:
When defining validation rules, you can use the on key to define when a validation rule should be applied. If left undefined, the rule will always be applied. Other valid values are create and update. Using one of these values will make the rule apply to only create or update operations.
Read the whole documentation page.
Example taken from there, pay attention to the on part.
$validator->add('picture', 'file', [
'rule' => ['mimeType', ['image/jpeg', 'image/png']],
'on' => function ($context) {
return !empty($context['data']['show_profile_picture']);
}
]);