[FRAME-176]: Delay Events Until Shutdown

dev/public/wp-content/plugins/library-testing/library-testing.php

@@ -31,3 +31,43 @@ function () {
 		do_action( 'stellarwp/telemetry/optin', 'telemetry-library' );
 	}
 );
+
+// If the 'Send Events' link was used, send some test events once.
+add_action(
+	'init',
+	function() {
+		if ( ! isset( $_GET['send-events'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
+			return;
+		}
+
+		do_action( 'stellarwp/telemetry/telemetry-prefix/event', 'opt-in', [ 'one' => 1 ] );
+		do_action( 'stellarwp/telemetry/telemetry-prefix/event', 'create-post', [ 'post-title' => 'This is my first post!' ] );
+		do_action( 'stellarwp/telemetry/telemetry-prefix/event', 'opt-out', [ 'one' => 1 ] );
+
+		wp_safe_redirect( remove_query_arg( 'send-events' ) );
+		exit;
+	}
+);
+
+/**
+ * Adds a helper link to the admin bar for sending a group of events.
+ *
+ * @param WP_Admin_Bar $admin_bar The adminbar class.
+ *
+ * @return void
+ */
+function add_event_send_link( $admin_bar ) {
+	global $wp;
+
+	$admin_bar->add_menu(
+		[
+			'id'    => 'send-events',
+			'title' => 'Send Events',
+			'href'  => add_query_arg( [ 'send-events' => true ], home_url( $wp->request ) ),
+			'meta'  => [
+				'title' => __( 'Send Events' ),
+			],
+		]
+	);
+}
+add_action( 'admin_bar_menu', 'add_event_send_link', 100, 1 );

src/Telemetry/Events/Event.php

@@ -21,6 +21,13 @@
  */
 class Event {
 
+	/**
+	 * The hook name for sending events asyncronously.
+	 *
+	 * @since TBD
+	 */
+	public const AJAX_ACTION = 'stellarwp_telemetry_send_event';
+
 	/**
 	 * An instance of the Telemetry class.
 	 *
@@ -77,6 +84,30 @@ public function send( string $name, array $data = [] ) {
 		return boolval( $response['status'] );
 	}
 
+	/**
+	 * Send batched events.
+	 *
+	 * @since TBD
+	 *
+	 * @param array $events An array of stored events to send to the telemetry server.
+	 *
+	 * @return bool
+	 */
+	public function send_batch( array $events ) {
+		$data = [
+			'token'  => $this->telemetry->get_token(),
+			'events' => $events,
+		];
+
+		$response = $this->telemetry->send( $data, $this->get_url() );
+
+		if ( ! isset( $response['status'] ) ) {
+			return false;
+		}
+
+		return boolval( $response['status'] );
+	}
+
 	/**
 	 * Gets the url used for sending events.
 	 *

src/Telemetry/Events/Event_Subscriber.php

@@ -9,6 +9,7 @@
 
 namespace StellarWP\Telemetry\Events;
 
+use StellarWP\Telemetry\Config;
 use StellarWP\Telemetry\Contracts\Abstract_Subscriber;
 
 /**
@@ -28,19 +29,78 @@ class Event_Subscriber extends Abstract_Subscriber {
 	 * @return void
 	 */
 	public function register() {
-		add_action( 'stellarwp/telemetry/event', [ $this, 'send_event' ], 10, 2 );
+		add_action( 'shutdown', [ $this, 'send_cached_events' ] );
+		add_action( 'stellarwp/telemetry/' . Config::get_hook_prefix() . 'event', [ $this, 'cache_event' ], 10, 2 );
+		add_action( 'wp_ajax_' . Event::AJAX_ACTION, [ $this, 'send_events' ], 10, 1 );
+		add_action( 'wp_ajax_nopriv_' . Event::AJAX_ACTION, [ $this, 'send_events' ], 10, 1 );
 	}
 
 	/**
-	 * Sends an event request to the Telemetry server.
+	 * Caches an event to be sent during shutdown.
 	 *
-	 * @since 2.1.0
+	 * @since TBD
+	 *
+	 * @param string $name         The name of the event.
+	 * @param array  $data         The data sent along with the event.
 	 *
-	 * @param string $name The name of the event to send.
-	 * @param array  $data Additional information to send with the event.
+	 * @return void
 	 */
-	public function send_event( string $name, array $data = [] ) {
-		$this->container->get( Event::class )->send( $name, $data );
+	public function cache_event( $name, $data ) {
+		$events = [];
+
+		if ( $this->container->has( 'events' ) ) {
+			$events = $this->container->get( 'events' );
+		}
+
+		$events[] = [
+			'name'         => $name,
+			'data'         => wp_json_encode( $data ),
+			'stellar_slug' => Config::get_stellar_slug(),
+		];
+
+		$this->container->bind( 'events', $events );
 	}
 
+	/**
+	 * Sends the events that have been stored for the current request.
+	 *
+	 * @since TBD
+	 *
+	 * @return void
+	 */
+	public function send_cached_events() {
+		if ( ! $this->container->has( 'events' ) ) {
+			return;
+		}
+
+		$url = admin_url( 'admin-ajax.php' );
+
+		wp_remote_post(
+			$url,
+			[
+				'blocking'  => false,
+				'sslverify' => false,
+				'body'      => [
+					'action' => Event::AJAX_ACTION,
+					'events' => $this->container->get( 'events' ),
+				],
+			]
+		);
+
+		$this->container->bind( 'events', [] );
+	}
+
+	/**
+	 * Send the event to the telemetry server.
+	 *
+	 * @since TBD
+	 *
+	 * @return void
+	 */
+	public function send_events() {
+		// Get the passed event array.
+		$events = filter_input( INPUT_POST, 'events', FILTER_DEFAULT, FILTER_REQUIRE_ARRAY ); // phpcs:ignore WordPressVIPMinimum.Security.PHPFilterFunctions.RestrictedFilter
+
+		$this->container->get( Event::class )->send_batch( $events );
+	}
 }