dantleech/argument-resolver

Resolve method arguments from an associative array

1.0.0 2018-09-30 09:50 UTC

This package is auto-updated.

Last update: 2020-03-14 12:52:10 UTC


README

Resolve and validate method arguments from an associative array.

  • Resolves arguments including default values from an associative array.
  • Throws exception if required arguments are missing.
  • Throws exception if extra arguments are provided.

Example

class Foobar
{
    public function execute(string $foobar, $barfoo = 'foobar')
    {
    }
}

$argumentResolver = new ArgumentResolver();
$arguments = $argumentResolver->resolveArguments(Foobar::class, 'execute', [
    'foobar' => 'hello'
]);

var_dump($arguments);
// array(2) {                       
//   [0] =>                         
//   string(5) "hello"              
//   [1] =>                         
//   string(6) "foobar"             
// }

$result = call_user_func([$myClass, 'myMethod'], $arguments);

Motivation

It is often desired that service have some runtime invocation configuration which is provided by the user (similar to Symfony Forms and the Symfony OptionResolver component, which does something like:

$resolver = new OptionsResolver();
$resolver->setDefault([
    'barfoo' => 'hello',
]);
$resolver->setRequired('foobar')l
$options = $resolver->resolve(['foobar' => 'hello']);

$myService->doSomething($options);

I have used this pattern in PHPBench and found it very useful for configuring services invocations at runtime. However it has drawbacks:

  • Your service is passed an untyped array.
  • The service has an implicit dependency on the options resolver.

This package does something similar to the options resolver, but uses the reflection information from the method to resolve the arguments.

Drawbacks

This method does mean that you cannot implement a interface for your service (e.g. execute($blah, array $config) as each service will have it's own signature execute($blah, $timeout = 1234, $iterations = 33).

Similar Libraries

https://github.com/sroze/ArgumentResolver does almost exactly the same thing