Middleware caller for PHP

Flexible and powerful middleware caller for PHP, supporting multiple middlewares in a queue with contexts and persistent data Unit tests have passed on versions: 5.6, 7.4, 8.1, 8.2 and 8.3

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Install

composer require vitorsreis/extend-caller

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Usage

Simple usage

use VSR\Extend\Caller;

$caller = new Caller(static function ($aaa, $bbb, $ccc = 3) { return "$aaa:$bbb:$ccc"; });
echo $caller->execute([1, 2, /* 3 */]); // output: 1:2:3
echo $caller->execute(['aaa' => 1, 'bbb' => 2, /* 'ccc' => 3 */]); // output: 1:2:3

Multiple middlewares

You can use multiple middlewares in queue, the result of each middleware is passed as argument to next middleware.

$caller = new Caller('ccc', 'ddd', ...);
$caller->prepend('aaa', 'bbb');
$caller->append('eee', 'fff', ...);
// queue: aaa -> bbb -> ccc -> ddd -> eee -> fff -> ...

Context param

Context contains all information about the current execution. Use an argument with the name "$context" with an omitted type or of type "mixed," or use any name with the type "\VSR\Extend\Caller\Context" in middlewares or in the constructor of a class if the middleware is a non-static class method at any position to receive the argument information.

use VSR\Extend\Caller\Context;

new Caller(function ($context) { ... });
new Caller(function (mixed $context) { ... }); # Explicit mixed type only PHP 8+
new Caller(function (Context $context) { ... });
new Caller(function (Context $custom_name_context) { ... });
new Caller(new class {
    public function __construct($context) { ... }
    public function __invoke($context) { ... }
}); // Call __invoke

Property	Description
$context->state	Current execution state
$context->cursor	Current execution position on queue middleware
$context->total	Total execution queue middlewares count
$context->startTime	Execution start time
$context->endTime	Execution end time
$context->time	Execution time
$context->result	Partial/Final execution result
$context->get($key, $default = null)	Get persistent data
$context->set($key, $value)	Set persistent data
$context->has($key)	Check if persistent data exists
$context->del($key)	Delete persistent data
$context->stop()	Stop queue execution
"$context" or $context->toString()	Result as string

You can persist data in context so that it is persisted in future callbacks.

$caller = new Caller();
$caller->append(static function (Context $context) {
    $context->set('xxx', $context->get('xxx', 0) + 10); # 2. Increment value: 5 + 10 = 15
});
$caller->append(static function ($context) {
    $context->set('xxx', $context->get('xxx', 0) + 15); # 3. Increment value: 15 + 15 = 30
});
$caller->context()->set('xxx', 5); # 1. Initial value: 5

$context = $caller->execute();
echo $context->get('xxx'); // output: "30"

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Supported middleware callback types

• Native function name

$caller = new \VSR\Extend\Caller("\\stripos");

• Function name

function callback($a, $b, $c = 3) { ... }
$caller = new \VSR\Extend\Caller("\\callback");

• Anonymous function

$caller = new \VSR\Extend\Caller(function ($a, $b, $c = 3) { ... });
$caller = new \VSR\Extend\Caller(static function ($a, $b, $c = 3) { ... });

• Arrow function, PHP 7.4+

$caller = new \VSR\Extend\Caller(fn($a, $b, $c = 3) => ...);
$caller = new \VSR\Extend\Caller(static fn($a, $b, $c = 3) => ...);

• Variable function

$callback = function ($a, $b, $c = 3) { ... };
$caller = new \VSR\Extend\Caller($callback);

$callback = static function ($a, $b, $c = 3) { ... };
$caller = new \VSR\Extend\Caller($callback);

• Class method

class AAA {
    public function method($a, $b, $c = 3) { ... }
}
$aaa = new AAA();

$caller = new \VSR\Extend\Caller("AAA::method"); // Call first constructor if exists and then method
$caller = new \VSR\Extend\Caller([ AAA::class, 'method' ]); // Call first constructor if exists and then method
$caller = new \VSR\Extend\Caller([ new AAA(), 'method' ]); // Call method
$caller = new \VSR\Extend\Caller([ $aaa, 'method' ]); // Call method

• Class static method

class BBB {
    public static function method($a, $b, $c = 3) { ... }
}
$bbb = new BBB();

$caller = new \VSR\Extend\Caller("BBB::method"); // Call static method
$caller = new \VSR\Extend\Caller([ BBB::class, 'method' ]); // Call static method
$caller = new \VSR\Extend\Caller([ new BBB(), 'method' ]); // Call static method
$caller = new \VSR\Extend\Caller([ $bbb, 'method' ]); // Call static method

• Class method with constructor

class CCC {
    public function __construct($d, $e, $f = 6) { ... }
    public function method($a, $b, $c = 3) { ... }
}

$caller = new \VSR\Extend\Caller("CCC::method"); // Call first constructor and then method
$caller = new \VSR\Extend\Caller([ CCC::class, "method" ]); // Call first constructor and then method

• Class name/object

class DDD {
    public function __invoke($a, $b, $c = 3) { ... }
}
$ddd = new DDD();

$caller = new \VSR\Extend\Caller("DDD"); // Call first constructor if exists and then __invoke
$caller = new \VSR\Extend\Caller(DDD::class); // Call first constructor if exists and then __invoke
$caller = new \VSR\Extend\Caller(new DDD()); // Call __invoke
$caller = new \VSR\Extend\Caller($ddd); // Call __invoke

• Anonymous class, PHP 7+

$caller = new \VSR\Extend\Caller(new class {
    public function __invoke($a, $b, $c = 3) { ... }
}); // Call __invoke