Event dispatcher system for the Requests library. HookManager is the interface; Hooks is the concrete implementation.

Source: wp-includes/Requests/src/HookManager.php, wp-includes/Requests/src/Hooks.php
Namespace: WpOrgRequests

HookManager (Interface)

interface HookManager {
    public function register( string $hook, callable $callback, int $priority = 0 );
    public function dispatch( string $hook, array $parameters = [] ): bool;
}

register()

dispatch()

Returns: bool — Success status.

Hooks (Implementation)

class Hooks implements HookManager

Properties

register()

public function register( string $hook, callable $callback, int $priority = 0 ): void

Register a callback for a hook. Multiple callbacks can be registered at the same priority.

Throws:

• InvalidArgument — When $hook is not a string
• InvalidArgument — When $callback is not callable
• InvalidArgument — When $priority is not an integer

Storage structure:

$this->hooks['hook.name'][0][] = $callback;  // priority 0
$this->hooks['hook.name'][-5][] = $callback; // priority -5 (runs first)

dispatch()

public function dispatch( string $hook, array $parameters = [] ): bool

Dispatch a hook event. Callbacks are executed in priority order (sorted by ksort), then in registration order within the same priority.

Parameters are passed as positional arguments using the spread operator ($callback(...$parameters)). Array keys are stripped via array_values() to prevent them being interpreted as named parameters in PHP 8.0+.

Returns: false if no callbacks are registered for the hook, true after executing callbacks.

Throws:

• InvalidArgument — When $hook is not a string
• InvalidArgument — When $parameters is not an array (strict check — Array* objects are rejected)

__wakeup()

public function __wakeup(): void

Throws LogicException — Hooks should never be unserialized.

Dispatch Order Example

$hooks = new Hooks();
$hooks->register('my.event', $callbackA, 10);   // runs third
$hooks->register('my.event', $callbackB, -5);   // runs first
$hooks->register('my.event', $callbackC, 0);    // runs second
$hooks->register('my.event', $callbackD, 10);   // runs fourth (same priority as A, registered after)

$hooks->dispatch('my.event', [&$data]);
// Execution order: B (-5) → C (0) → A (10) → D (10)

Usage in the Library

Hooks is automatically instantiated in Requests::set_defaults() when $options['hooks'] is empty. Auth handlers, proxy handlers, and cookie jars register themselves with the hooks system via their register() methods.

See Hook Points for all dispatched hooks.