Supported Versions: PHP 4, PHP 5, PHP 7, PHP 8
Checks if a value exists in an array
in_array(mixed $needle, array $haystackbool $strict false): bool
            ! isset($event['requestContext']['domainName']) ||

            ! isset(
$event['requestContext']['apiId']) ||

            ! isset(
$event['requestContext']['stage']) ||

            ! 
in_array(

                
$event['requestContext']['eventType'],

                [

                    
'CONNECT',

                    
'DISCONNECT',

                    
'MESSAGE',

                ],

                
true

            
)

        ) {

            throw new 
InvalidLambdaEvent('Websocket'$event);

        }