lotharthesavior/client.php

## client.php
<?php


Co\run(function() {

    go(function() {
        echo "==========================================" . PHP_EOL;
        echo file_get_contents('http://localhost:8282/requestA') . PHP_EOL;
        echo "==========================================" . PHP_EOL;
    });

    go(function() {
        sleep(1);
        echo "==========================================" . PHP_EOL;
        echo file_get_contents('http://localhost:8282/requestB') . PHP_EOL;
        echo "==========================================" . PHP_EOL;
    });

});

## server.php
<?php

$counter = new Swoole\Atomic;
$lock = new Swoole\Atomic;

$server = new Swoole\Http\Server('0.0.0.0', 8282);

$server->on('request', function(\Swoole\Http\Request $request, \Swoole\Http\Response $response) use ($server, &$lock, &$counter) {
    $worker_info = "(worker: " . $server->worker_id . ")";

    switch ($request->server['request_uri']) {
        case '/requestA':
            // interrupt if there is a request A already waiting for a request B
            if ($counter->get() === 1) {
                // cancel request A
                $lock->wakeup();
                $counter->set(0);
                echo $worker_info . " Interrupted!" . PHP_EOL;
                $output = 'interrupted!';

            // proceed if there is no request A already waiting
            } else {
                // start to wait for request B
                $output = 'request-a';
                $counter->set(1);
                $lock->wait(60);
                echo $worker_info . " waited..." . PHP_EOL;
            }

            break;
        case '/requestB':
            // avoid continuing without waiting A request
            if ($counter->get() === 0) {
                $output = 'Waiting for Request A.' . PHP_EOL;
                break;
            }

            $output = 'request-b';
            echo $worker_info . " waking..." . PHP_EOL;
            $lock->wakeup();
            $counter->set(0);
            echo $worker_info . " woke..." . PHP_EOL;
            break;
        default:
            $output = <<<HTML
<div><a target="_blank" href="/requestA">Request A</a></div>
<div><a target="_blank" href="/requestB">Request B</a></div>
HTML;
            break;
    }

    $response->end($output);
});

$server->start();
	<?php


	Co\run(function() {

	go(function() {
	echo "==========================================" . PHP_EOL;
	echo file_get_contents('http://localhost:8282/requestA') . PHP_EOL;
	echo "==========================================" . PHP_EOL;
	});

	go(function() {
	sleep(1);
	echo "==========================================" . PHP_EOL;
	echo file_get_contents('http://localhost:8282/requestB') . PHP_EOL;
	echo "==========================================" . PHP_EOL;
	});

	});
	<?php

	$counter = new Swoole\Atomic;
	$lock = new Swoole\Atomic;

	$server = new Swoole\Http\Server('0.0.0.0', 8282);

	$server->on('request', function(\Swoole\Http\Request $request, \Swoole\Http\Response $response) use ($server, &$lock, &$counter) {
	$worker_info = "(worker: " . $server->worker_id . ")";

	switch ($request->server['request_uri']) {
	case '/requestA':
	// interrupt if there is a request A already waiting for a request B
	if ($counter->get() === 1) {
	// cancel request A
	$lock->wakeup();
	$counter->set(0);
	echo $worker_info . " Interrupted!" . PHP_EOL;
	$output = 'interrupted!';

	// proceed if there is no request A already waiting
	} else {
	// start to wait for request B
	$output = 'request-a';
	$counter->set(1);
	$lock->wait(60);
	echo $worker_info . " waited..." . PHP_EOL;
	}

	break;
	case '/requestB':
	// avoid continuing without waiting A request
	if ($counter->get() === 0) {
	$output = 'Waiting for Request A.' . PHP_EOL;
	break;
	}

	$output = 'request-b';
	echo $worker_info . " waking..." . PHP_EOL;
	$lock->wakeup();
	$counter->set(0);
	echo $worker_info . " woke..." . PHP_EOL;
	break;
	default:
	$output = <<<HTML
	<div><a target="_blank" href="/requestA">Request A</a></div>
	<div><a target="_blank" href="/requestB">Request B</a></div>
	HTML;
	break;
	}

	$response->end($output);
	});

	$server->start();