Question

I’ve got a Validator class which creates an instance of a Validations class, which contains all the validation methods. When a validation is performed, __call in Validator is used to dispatch a call Validator->validate_method to Validations->method.

So for instance, there is a method in Validations called length_of. When the following code is run:

$v = new Validator();
$v->validate_length_of(...);

the length_of validation in the Validations class is executed.

In order to ensure that __call doesn’t try to dispatch to an invalid or non-public Validation method, I use ReflectionMethod to check the specified method:

$method = new ReflectionMethod($this->validations, $validation_method);
if (!$method->isPublic())
{
  // error
}

I’m pretty sure this is the only way to determine whether or not a method is public, but I’m not sure if Reflection is appropriate to have in production code. Is this a code smell?

Answer 1

You really shouldn’t use Reflection in production code. Why don’t you use is_callable here?

if (!is_callable(array('Validations', $validation_method)) {
    throw new LogicException('method does not exist');
}

This checks that the Validations class has a static method $validation_method and ensures that you may call it from current context. Actually this gives you even more flexibility then reflection, because this takes __call methods and similar stuff into account that Reflection doesn’t.