How To Build A Real-Time Commenting System - Practical JavaScript Techniques - page 115

};

var socketId = getSocketId ();
if ( socketId !== null ) {
data . socket_id = socketId ;

}

postComment ( data );

return false ;

}

function getSocketId () {
if ( pusher && pusher . connection . state === 'connected' ) {
return pusher . connection . socket_id ;

}
return null ;

}

The changes we've made are:

•

A new function called getSocketId has been added to get the socket_id . It wraps a

check to ensure that the pusher variable has been set and also that the client is
connected to Pusher.

•

The handleSubmit has been updated to check to see if a socket_id is available. If it is,

this information is posted to the server along with the comment data.

On the server we need to use the socket_id parameter if it is present and therefore exclude
the connection and user who submitted the comment, or pass in null if it's not:

$channel_name = 'comments-' . $added [ 'comment_post_ID' ];
$event_name = 'new_comment' ;
$socket_id = ( isset ( $_POST [ 'socket_id' ]) ? $_POST [ 'socket_id' ]: null );

$pusher = new Pusher ( APP_KEY , APP_SECRET , APP_ID );
$pusher -& gt ; trigger ( $channel_name , $event_name , $added , $socket_id );