How to find out with standard PHP tools whether arguments are required to call a method?

Question

PHP

I am writing my bike for experience, the routing is done as in CI:
CodeIgniter uses an approach based on address segments :
www.your-site.com/news/article/my_article
are built like this:
www.your-site.com/class/function/arg
The first segment describes the class controller that is accessed.
In the second segment, there is a reference to the function function or method to be called.
The third and subsequent segments describe the variables that will be passed to this function.
In CI, a method might look like this:
function hello ($name, $id) {
echo "\$name = $name";
echo "
";
echo "$id";
}
Now the question is, in cases where one of the arguments for the method was not passed to the url, an error naturally occurs.
How can I check how many arguments are required to call the method? You need to check before calling, so func_num_args will not work use.Or
maybe another way out of the situation, tell me?Thank you very much in advance.

Answer 1

php.net/manual/en/book.reflection.php

function test_function($param1, $param2 = NULL)
{
  echo $param1;
}

$ref_function = new ReflectionFunction('test_function');

foreach($ref_function->getParameters() as $param)
{
  var_dump($param->isOptional());
}

var_dump($ref_function->getNumberOfRequiredParameters());

will output:
bool(false)
bool(true)
int(1)


Answer 2

In my opinion, it is better to catch errors at the function level, like:

function my_action($param1 = null, $param2 = null) {
if($param1 === null) {
throw new Exception('');
}
}

Answer 3

Have you watched how CI is done?