UsePubSub.php — WooCommerce 10.9.3

woocommerce / packages / blueprint / src / UsePubSub.php

woocommerce / packages / blueprint / src Last commit date

UsePubSub.php

68 lines

1	<?php
2
3	namespace Automattic\WooCommerce\Blueprint;
4
5	trait UsePubSub {
6
7	/**
8	* Subscribers.
9	*
10	* @var array
11	*/
12	private array $subscribers = array();
13
14	/**
15	* Subscribe to an event with a callback.
16	*
17	* @param string $event The event name.
18	* @param callable $callback The callback to execute when the event is published.
19	* @return void
20	*/
21	public function subscribe( string $event, callable $callback ): void {
22	if ( ! isset( $this->subscribers[ $event ] ) ) {
23	$this->subscribers[ $event ] = array();
24	}
25
26	$this->subscribers[ $event ][] = $callback;
27	}
28
29	/**
30	* Publish an event to all subscribers.
31	*
32	* @param string $event The event name.
33	* @param mixed ...$args Arguments to pass to the callbacks.
34	* @return void
35	*/
36	public function publish( string $event, ...$args ): void {
37	if ( ! isset( $this->subscribers[ $event ] ) ) {
38	return;
39	}
40
41	foreach ( $this->subscribers[ $event ] as $callback ) {
42	call_user_func( $callback, ...$args );
43	}
44	}
45
46	/**
47	* Unsubscribe a specific callback from an event.
48	*
49	* @param string $event The event name.
50	* @param callable $callback The callback to remove.
51	* @return void
52	*/
53	public function unsubscribe( string $event, callable $callback ): void {
54	if ( ! isset( $this->subscribers[ $event ] ) ) {
55	return;
56	}
57
58	$this->subscribers[ $event ] = array_filter(
59	$this->subscribers[ $event ],
60	fn( $subscriber ) => $subscriber !== $callback
61	);
62
63	if ( empty( $this->subscribers[ $event ] ) ) {
64	unset( $this->subscribers[ $event ] );
65	}
66	}
67	}
68