Cacher is the code snippet organizer for pro developers

<?php
/*
Plugin Name: WPMDB Pro Migration Complete Notifications
Plugin URI: http://deliciousbrains.com
Description: Get notified when a migration completes
Author: Delicious Brains
Version: 0.0
Author URI: http://deliciousbrains.com
*/

add_action( 'admin_enqueue_scripts', 'jg_heartbeat_enqueue' );
function jg_heartbeat_enqueue( $hook ) {
	// Make sure the JS part of the Heartbeat API is loaded.
	wp_enqueue_script( 'heartbeat' );
	add_action( 'admin_print_footer_scripts', 'jg_heartbeat_js', 20 );
}

function jg_heartbeat_js() {
	// only run heartbeats on WP Migrate DB Pro page
	if ( ! isset( $_GET['page'] ) || $_GET['page'] != 'wp-migrate-db-pro' ) {
		return;
	}
	?>
	<script>
	(function($){
		// Don't continue if browser not capable
		if ( !("Notification" in window) ) {
			return;
		}
		// Get permission if not already granted
		if ( 'granted' !== Notification.permission ) {
			Notification.requestPermission();
		}

		// Hook into the heartbeat-send
		$(document).on('heartbeat-send', function(e, data) {
			data['wpmdb_mig_complete_heartbeat'] = 'check';
		});

		// Listen for the custom event "heartbeat-tick" on $(document).
		$(document).on( 'heartbeat-tick', function(e, data) {
			//return if flag is not set
			if ( ! data['wpmdb_mig_complete_heartbeat'] ) {
				return;
			}

			//fire notification
			if ( 'granted' === Notification.permission ) {
				var notification = new Notification( "WP Migrate DB Pro Migration complete!", { body: 'Your migration has completed!', icon: 'https://example.com/logo.png' } );
			}
		});
	}(jQuery));
	</script>
	<?php
}

add_filter( 'heartbeat_received', 'jg_heartbeat_received', 10, 2 );
function jg_heartbeat_received( $response, $data ) {
	if( $data['wpmdb_mig_complete_heartbeat'] == 'check' ) {
		if( get_site_transient( 'wpmdb_mig_is_complete' ) ) {
			$response['wpmdb_mig_complete_heartbeat'] = "complete";
			delete_site_transient( 'wpmdb_mig_is_complete' );
		}
	}
	return $response;
}

add_action( 'wpmdb_migration_complete', 'jg_set_complete_transient', 2, 20 );
function jg_set_complete_transient( $action, $url ) {
	global $wp_current_filter;
	$is_remote = strstr($wp_current_filter[0], 'nopriv') ? true : false;
	// only set transient on site running migration
	if ( ! $is_remote ) {
		set_site_transient( 'wpmdb_mig_is_complete', true, 500 );
	}
}