williamdes/PHP_SOCKET_CLIENT_SERVER.md

## client.php
<?php

declare(strict_types = 1);

require_once __DIR__ . DIRECTORY_SEPARATOR . 'WorkerSocket.php';

$w = new WorkerSocket(
    __DIR__ . DIRECTORY_SEPARATOR . 'server.sock'
);

$w->connect(__DIR__ . '/' . time() . '-client.sock');

$i = 10;
while ($i > 0) {
    [$buf, $from] = $w->sendMessage('Hi number: ' . --$i);
    echo '[DEBUG]' . ' Received ' . $buf . ' from ' . $from . PHP_EOL;
    sleep(1);
}
$w->sendMessage('STOP');
?>

## PHP_SOCKET_CLIENT_SERVER.md

      
    Raw
  

              PHP_SOCKET_CLIENT_SERVER.md
            
          
    PHP Socket client server example

With this example you will be able to use modern PHP code and have multiple clients connected.
The code is inspired and sourced from the of the posted notes here.
If you CTRL-C stopped the server, run the script twice. The first time will clean up the left over socket. Or just remove the socket file before starting the server.
There is a "magic" command (STOP) in the code to stop the server, you can easily remove it.
server console

$ php -f server.php 
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 9 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 8 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 7 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 6 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 5 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 4 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 3 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 2 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 1 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received Hi number: 0 from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Ready to receive...
[DEBUG] Received STOP from /mnt/Dev/@williamdes/php/1620432655-client.sock
[DEBUG] Request processed
[DEBUG] Disconnecting
worker 1 console

$ php -f client.php 
[DEBUG] Received Hi number: 9->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 8->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 7->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 6->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 5->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 4->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 3->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 2->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 1->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Received Hi number: 0->Response from /mnt/Dev/@williamdes/php/server.sock
[DEBUG] Disconnecting

  
## server.php
<?php

declare(strict_types = 1);

require_once __DIR__ . DIRECTORY_SEPARATOR . 'WorkerSocket.php';

$w = new WorkerSocket(
    __DIR__ . DIRECTORY_SEPARATOR . 'server.sock'
);

$w->connect();
$w->listen();

?>

## WorkerSocket.php
<?php

declare(strict_types = 1);

/**
 * @license UNLICENSE
 * @co-author William Desportes <williamdes [at] wdes [dot] fr>
 * @source https://www.php.net/manual/fr/function.socket-create.php#108535
 */
class WorkerSocket
{

    /**
     * @var string
     */
    private $serverSocketFile;

    /**
     * @var resource
     */
    private $openSocket;

    /**
     * @var string
     */
    private $openSocketFile;

    /**
     * @var bool
     */
    private $listen = true;

    public function __construct(string $serverSocketFile)
    {
        if (! extension_loaded('sockets')) {
            echo '[ERROR]' . ' The sockets extension is not loaded.' . PHP_EOL;
            exit(1);
        }
        $this->serverSocketFile = $serverSocketFile;
    }

    public function __destruct()
    {
        $this->disconnect();
    }

    public function connect(?string $clientSocket = null): void
    {
        $this->openSocketFile = $clientSocket === null ? $this->serverSocketFile : $clientSocket;
        // create unix tcp socket
        $socket = socket_create(AF_UNIX, SOCK_RAW, 0);
        if ($socket === false) {
            echo '[ERROR]' . ' Unable to create AF_UNIX socket.' . PHP_EOL;
            exit(1);
        }
        $this->openSocket = $socket;

        // same socket will be used in recv_from and send_to
        if (! socket_bind($this->openSocket, $this->openSocketFile)) {
            echo '[ERROR]' . ' Unable to bind to ' . $this->openSocketFile . PHP_EOL;
            exit(1);
        }
    }

    public function disconnect(): void
    {
        $this->listen = false;
        // close socket and delete own .sock file
        if (is_resource($this->openSocket)) {
            socket_close($this->openSocket);
        }
        if (file_exists($this->openSocketFile)) {
            unlink($this->openSocketFile);
        }
        $this->logger->debug('Disconnecting');
    }

    public function listen(): void
    {
        while ($this->listen) { // server never exits unless a magic command is sent
            // receive query
            if (!socket_set_block($this->openSocket)) {
                echo '[ERROR]' . ' Unable to set blocking mode for socket' . PHP_EOL;
                return;
            }
            echo '[DEBUG]' . ' Ready to receive...' . PHP_EOL;
            // will block to wait client query
            [$buf, $from] = $this->receive();

            // NOTE: remove this code to disable the magic STOP command
            if ($buf === 'STOP') {
                $this->listen = false;
            }

            echo '[DEBUG]' . ' Received ' . $buf . ' from ' . $from . PHP_EOL;

            $buf .= '->Response'; // process client query here

            // send response
            if (!socket_set_nonblock($this->openSocket)) {
                echo '[ERROR]' . ' Unable to set nonblocking mode for socket' . PHP_EOL;
                return;
            }

            // client side socket filename is known from client request: $from
            if (! $this->send($buf, $from)) {
                echo '[ERROR]' . ' Sending failed' . PHP_EOL;
                continue;
            }
            echo '[DEBUG]' . ' Request processed' . PHP_EOL;
        }
    }

    public function sendMessage(string $message): ?array
    {
        if (! $this->send($message, $this->serverSocketFile)) {
            return null;
        }

        // use socket to receive data
        if (!socket_set_block($this->openSocket)) {
            echo '[ERROR]' . ' Unable to set blocking mode for socket' . PHP_EOL;
            return null;
        }
        // will block to wait server response
        return $this->receive();
    }

    private function send(string $msg, string $receivingAddress): bool
    {
        $len = strlen($msg);
        // at this point 'server' process must be running and bound to receive from server.sock
        $bytes_sent = socket_sendto($this->openSocket, $msg, $len, 0, $receivingAddress);
        if ($bytes_sent === -1) {
            echo '[ERROR]' . ' An error occurred while sending to the socket' . PHP_EOL;
            return false;
        }
        if ($bytes_sent !== $len) {
            echo '[ERROR]' . $bytes_sent . ' bytes have been sent instead of the ' . $len . ' bytes expected' . PHP_EOL;
            return false;
        }
        return true;
    }

    /**
     * @return string[]
     */
    private function receive(): array
    {
        $buf  = '';
        $from = '';
        // will block to wait server response
        $bytes_received = socket_recvfrom($this->openSocket, $buf, MSG_WAITFORONE, 0, $from);
        if ($bytes_received === -1) {
            echo '[ERROR]' . ' An error occurred while receiving from the socket' . PHP_EOL;
            return [$buf, $from];
        }
        return [$buf, $from];
    }

}
	<?php

	declare(strict_types = 1);

	require_once __DIR__ . DIRECTORY_SEPARATOR . 'WorkerSocket.php';

	$w = new WorkerSocket(
	__DIR__ . DIRECTORY_SEPARATOR . 'server.sock'
	);

	$w->connect(__DIR__ . '/' . time() . '-client.sock');

	$i = 10;
	while ($i > 0) {
	[$buf, $from] = $w->sendMessage('Hi number: ' . --$i);
	echo '[DEBUG]' . ' Received ' . $buf . ' from ' . $from . PHP_EOL;
	sleep(1);
	}
	$w->sendMessage('STOP');
	?>
	<?php

	declare(strict_types = 1);

	/**
	* @license UNLICENSE
	* @co-author William Desportes <williamdes [at] wdes [dot] fr>
	* @source https://www.php.net/manual/fr/function.socket-create.php#108535
	*/
	class WorkerSocket
	{

	/**
	* @var string
	*/
	private $serverSocketFile;

	/**
	* @var resource
	*/
	private $openSocket;

	/**
	* @var string
	*/
	private $openSocketFile;

	/**
	* @var bool
	*/
	private $listen = true;

	public function __construct(string $serverSocketFile)
	{
	if (! extension_loaded('sockets')) {
	echo '[ERROR]' . ' The sockets extension is not loaded.' . PHP_EOL;
	exit(1);
	}
	$this->serverSocketFile = $serverSocketFile;
	}

	public function __destruct()
	{
	$this->disconnect();
	}

	public function connect(?string $clientSocket = null): void
	{
	$this->openSocketFile = $clientSocket === null ? $this->serverSocketFile : $clientSocket;
	// create unix tcp socket
	$socket = socket_create(AF_UNIX, SOCK_RAW, 0);
	if ($socket === false) {
	echo '[ERROR]' . ' Unable to create AF_UNIX socket.' . PHP_EOL;
	exit(1);
	}
	$this->openSocket = $socket;

	// same socket will be used in recv_from and send_to
	if (! socket_bind($this->openSocket, $this->openSocketFile)) {
	echo '[ERROR]' . ' Unable to bind to ' . $this->openSocketFile . PHP_EOL;
	exit(1);
	}
	}

	public function disconnect(): void
	{
	$this->listen = false;
	// close socket and delete own .sock file
	if (is_resource($this->openSocket)) {
	socket_close($this->openSocket);
	}
	if (file_exists($this->openSocketFile)) {
	unlink($this->openSocketFile);
	}
	$this->logger->debug('Disconnecting');
	}

	public function listen(): void
	{
	while ($this->listen) { // server never exits unless a magic command is sent
	// receive query
	if (!socket_set_block($this->openSocket)) {
	echo '[ERROR]' . ' Unable to set blocking mode for socket' . PHP_EOL;
	return;
	}
	echo '[DEBUG]' . ' Ready to receive...' . PHP_EOL;
	// will block to wait client query
	[$buf, $from] = $this->receive();

	// NOTE: remove this code to disable the magic STOP command
	if ($buf === 'STOP') {
	$this->listen = false;
	}

	echo '[DEBUG]' . ' Received ' . $buf . ' from ' . $from . PHP_EOL;

	$buf .= '->Response'; // process client query here

	// send response
	if (!socket_set_nonblock($this->openSocket)) {
	echo '[ERROR]' . ' Unable to set nonblocking mode for socket' . PHP_EOL;
	return;
	}

	// client side socket filename is known from client request: $from
	if (! $this->send($buf, $from)) {
	echo '[ERROR]' . ' Sending failed' . PHP_EOL;
	continue;
	}
	echo '[DEBUG]' . ' Request processed' . PHP_EOL;
	}
	}

	public function sendMessage(string $message): ?array
	{
	if (! $this->send($message, $this->serverSocketFile)) {
	return null;
	}

	// use socket to receive data
	if (!socket_set_block($this->openSocket)) {
	echo '[ERROR]' . ' Unable to set blocking mode for socket' . PHP_EOL;
	return null;
	}
	// will block to wait server response
	return $this->receive();
	}

	private function send(string $msg, string $receivingAddress): bool
	{
	$len = strlen($msg);
	// at this point 'server' process must be running and bound to receive from server.sock
	$bytes_sent = socket_sendto($this->openSocket, $msg, $len, 0, $receivingAddress);
	if ($bytes_sent === -1) {
	echo '[ERROR]' . ' An error occurred while sending to the socket' . PHP_EOL;
	return false;
	}
	if ($bytes_sent !== $len) {
	echo '[ERROR]' . $bytes_sent . ' bytes have been sent instead of the ' . $len . ' bytes expected' . PHP_EOL;
	return false;
	}
	return true;
	}

	/**
	* @return string[]
	*/
	private function receive(): array
	{
	$buf = '';
	$from = '';
	// will block to wait server response
	$bytes_received = socket_recvfrom($this->openSocket, $buf, MSG_WAITFORONE, 0, $from);
	if ($bytes_received === -1) {
	echo '[ERROR]' . ' An error occurred while receiving from the socket' . PHP_EOL;
	return [$buf, $from];
	}
	return [$buf, $from];
	}

	}