How to send data to a specific client in Workerman

When using Worker as the server without using GatewayWorker, how to push messages to a specific user?

<?php
use Workerman\Worker;
use Workerman\Connection\TcpConnection;
require_once __DIR__ . '/vendor/autoload.php';

// Initialize a worker container, listening on port 1234
$worker = new Worker('websocket://workerman.net:1234');
// ====The number of processes must be set to 1====
$worker->count = 1;
// Add a new property to save the mapping of uid to connection (uid is the user id or the unique identifier of the client)
$worker->uidConnections = array();
// Callback function to execute when a client sends a message
$worker->onMessage = function(TcpConnection $connection, $data)
{
    global $worker;
    // Check if the current client has been validated, i.e., if the uid has been set
    if(!isset($connection->uid))
    {
       // If not validated, the first package is treated as the uid (not a real verification for demonstration purpose)
       $connection->uid = $data;
       /* Save the mapping of uid to connection, so that connections can be easily found by uid,
        * and implement targeted data push for a specific uid
        */
       $worker->uidConnections[$connection->uid] = $connection;
       return $connection->send('login success, your uid is ' . $connection->uid);
    }
    // Other logic, sending to a specific uid or broadcasting globally
    // If the message format is uid:message, it will be sent to the uid
    // If uid is 'all', it will be broadcast to all
    list($recv_uid, $message) = explode(':', $data);
    // Global broadcast
    if($recv_uid == 'all')
    {
        broadcast($message);
    }
    // Send to a specific uid
    else
    {
        sendMessageByUid($recv_uid, $message);
    }
};

// When a client connection is closed
$worker->onClose = function(TcpConnection $connection)
{
    global $worker;
    if(isset($connection->uid))
    {
        // Delete the mapping when the connection is closed
        unset($worker->uidConnections[$connection->uid]);
    }
};

// Push data to all validated users
function broadcast($message)
{
   global $worker;
   foreach($worker->uidConnections as $connection)
   {
        $connection->send($message);
   }
}

// Push data to a specific uid
function sendMessageByUid($uid, $message)
{
    global $worker;
    if(isset($worker->uidConnections[$uid]))
    {
        $connection = $worker->uidConnections[$uid];
        $connection->send($message);
    }
}

// Run all workers (actually only one is defined currently)
Worker::runAll();

Note:

The above example can push messages to specific uids, and although it is a single process, it can support up to 100,000 online users.

Please note that this example can only have a single process, meaning $worker->count must be set to 1. To support multiple processes or server clusters, the Channel component needs to be used for inter-process communication. The development is also very simple and can be referred to in the section Channel component cluster push example.

If you want to push messages to clients in other systems, you can refer to the section Push in other projects