Swoole是一個強大的工具，它允許PHP開發(fā)人員編寫高性能高并發(fā)的TCP、UDP、Unix Socket、HTTP、WebSocket等服務(wù)，從而讓PHP可以超越Web領(lǐng)域的局限。

特別值得一提的是Swoole4協(xié)程的成熟，將PHP帶入了前所未有的時代。通過協(xié)程，我們可以實現(xiàn)異步非阻塞的編程方式，大大提升了程序的性能。

Swoole4協(xié)程為性能的提升提供了獨一無二的可能性。通過使用協(xié)程，我們可以在一個線程中同時執(zhí)行多個任務(wù)，而不需要創(chuàng)建多個線程或進(jìn)程。這樣可以減少上下文切換的開銷，提高服務(wù)器的吞吐量。

除了協(xié)程，Swoole還提供了許多其他的功能，如事件驅(qū)動、異步網(wǎng)絡(luò)通信等。這些功能讓PHP開發(fā)人員可以更加靈活地處理各種網(wǎng)絡(luò)編程需求，并且提供了更好的性能和可擴展性。

Swoole是一個功能強大的網(wǎng)絡(luò)通信框架，適用于互聯(lián)網(wǎng)、移動通信、云計算、網(wǎng)絡(luò)游戲、物聯(lián)網(wǎng)（IOT）、車聯(lián)網(wǎng)、智能家居等多個領(lǐng)域。通過使用PHP + Swoole，企業(yè)的IT研發(fā)團(tuán)隊可以顯著提升效率，將更多精力專注于開發(fā)創(chuàng)新產(chǎn)品。

HTTP Server

//高性能HTTP服務(wù)器
$http = new Swoole\Http\Server("127.0.0.1", 9501);
$http->on("start", function ($server) {
  echo "Swoole http server is started at http://127.0.0.1:9501\n";
});
  $http->on("request", function ($request, $response) {
  $response->header("Content-Type", "text/plain");
  $response->end("Hello World\n");});
  $http->start();

WebSocket Server

$server = new Swoole\Websocket\Server("127.0.0.1", 9502);$server->on('open', function($server, $req) {
echo "connection open: {$req->fd}\n";
});
$server->on('message', function($server, $frame) {
echo "received message: {$frame->data}\n";
$server->push($frame->fd, json_encode(["hello", "world"]));
});
$server->on('close', function($server, $fd) {
echo "connection close: {$fd}\n";});
$server->start();

TCP Server

$server = new Swoole\Server("127.0.0.1", 9503);
$server->on('connect', function ($server, $fd){
echo "connection open: {$fd}\n";});
$server->on('receive', function ($server, $fd, $reactor_id, $data) {
$server->send($fd, "Swoole: {$data}");
$server->close($fd);});$server->on('close', function ($server, $fd) {
echo "connection close: {$fd}\n";});
$server->start();

UDP Server

$serv = new Swoole\Server("127.0.0.1", 9502, SWOOLE_PROCESS, SWOOLE_SOCK_UDP);
//監(jiān)聽數(shù)據(jù)接收事件
$serv->on('Packet', function ($serv, $data, $clientInfo) {
$serv->sendto($clientInfo['address'], $clientInfo['port'], "Server ".$data);
var_dump($clientInfo);});
//啟動服務(wù)器$serv->start();

Task

$server = new Swoole\Server("127.0.0.1", 9502);
$server->set(array('task_worker_num' => 4));
$server->on('receive', function($server, $fd, $reactor_id, $data) {
$task_id = $server->task("Async");
echo "Dispatch AsyncTask: [id=$task_id]\n";});
$server->on('task', function ($server, $task_id, $reactor_id, $data) {
echo "New AsyncTask[id=$task_id]\n";  $server->finish("$data -> OK");});
$server->on('finish', function ($server, $task_id, $data) {
echo "AsyncTask[$task_id] finished: {$data}\n";});
$server->start();

Coroutine

在一個進(jìn)程內(nèi)一秒內(nèi)完成1萬次睡眠、讀取、寫入、檢查和刪除文件操作，以及使用PDO和MySQLi與數(shù)據(jù)庫進(jìn)行通信1萬次，創(chuàng)建TCP服務(wù)器和多個客戶端進(jìn)行相互通信1萬次，創(chuàng)建UDP服務(wù)器和多個客戶端進(jìn)行相互通信1萬次。

Swoole\Runtime::enableCoroutine();
//此行代碼后，文件操作，sleep，Mysqli，PDO，streams等都變成異步IO，見文檔'一鍵協(xié)程化'章節(jié)$s = microtime(true);
//Co/run()見文檔'協(xié)程容器'章節(jié)Co\run(function() {
// i just want to sleep...for ($c = 100; $c--;) {
go(function () {
for ($n = 100; $n--;) {
usleep(1000);
}
});}
// 10k file read and writefor ($c = 100; $c--;) {
go(function () use ($c) {
$tmp_filename = "/tmp/test-{$c}.php";
for ($n = 100; $n--;) {
$self = file_get_contents(__FILE__);
file_put_contents($tmp_filename, $self);
assert(file_get_contents($tmp_filename) === $self);
}    
unlink($tmp_filename);
});}
// 10k pdo and mysqli readfor ($c = 50; $c--;) {
go(function () {
$pdo = new PDO('mysql:host=127.0.0.1;dbname=test;charset=utf8', 'root', 'root');
$statement = $pdo->prepare('SELECT * FROM `user`');
for ($n = 100; $n--;) {
$statement->execute();
assert(count($statement->fetchAll()) > 0);
}
});}for ($c = 50; $c--;) {
go(function () {
$mysqli = new Mysqli('127.0.0.1', 'root', 'root', 'test');
$statement = $mysqli->prepare('SELECT `id` FROM `user`');
for ($n = 100; $n--;) {
$statement->bind_result($id);
$statement->execute();
$statement->fetch();
assert($id > 0);
}
});}
// php_stream tcp server & client with 12.8k requests in single processfunction tcp_pack(string $data): string{  
return pack('n', strlen($data)) . $data;}function tcp_length(string $head): int{  
return unpack('n', $head)[1];}go(function () {
$ctx = stream_context_create(['socket' => ['so_reuseaddr' => true, 'backlog' => 128]]);  
$socket = stream_socket_server(    
'tcp://0.0.0.0:9502',    
$errno, $errstr, STREAM_SERVER_BIND | STREAM_SERVER_LISTEN, $ctx  );  
if (!$socket) {
echo "$errstr ($errno)\n";
} else {
$i = 0;
while ($conn = stream_socket_accept($socket, 1)) {
stream_set_timeout($conn, 5);
for ($n = 100; $n--;) {
$data = fread($conn, tcp_length(fread($conn, 2)));
assert($data === "Hello Swoole Server #{$n}!");
fwrite($conn, tcp_pack("Hello Swoole Client #{$n}!"));
}
if (++$i === 128) {
fclose($socket);
break;
}
}
}});for ($c = 128; $c--;) {
go(function () {
$fp = stream_socket_client("tcp://127.0.0.1:9502", $errno, $errstr, 1);
if (!$fp) {
echo "$errstr ($errno)\n";
} else {
stream_set_timeout($fp, 5);
for ($n = 100; $n--;) {
fwrite($fp, tcp_pack("Hello Swoole Server #{$n}!"));
$data = fread($fp, tcp_length(fread($fp, 2)));
assert($data === "Hello Swoole Client #{$n}!");
}      
fclose($fp);
}
});}// udp server & client with 12.8k requests in single processgo(function () {
$socket = new Swoole\Coroutine\Socket(AF_INET, SOCK_DGRAM, 0);
$socket->bind('127.0.0.1', 9503);  $client_map = [];
for ($c = 128; $c--;) {
for ($n = 0; $n < 100; $n++) { $recv = $socket->recvfrom($peer);
$client_uid = "{$peer['address']}:{$peer['port']}";
$id = $client_map[$client_uid] = ($client_map[$client_uid] ?? -1) + 1;
 assert($recv === "Client: Hello #{$id}!");
$socket->sendto($peer['address'], $peer['port'], "Server: Hello #{$id}!");
}
}
$socket->close();});for ($c = 128; $c--;) {
go(function () {
$fp = stream_socket_client("udp://127.0.0.1:9503", $errno, $errstr, 1);
if (!$fp) {
echo "$errstr ($errno)\n";
} else {
for ($n = 0; $n < 100; $n++) {
fwrite($fp, "Client: Hello #{$n}!");
$recv = fread($fp, 1024);
list($address, $port) = explode(':', (stream_socket_get_name($fp, true)));
assert($address === '127.0.0.1' && (int)$port === 9503);
assert($recv === "Server: Hello #{$n}!");
}      fclose($fp);
}
});}});echo 'use ' . (microtime(true) - $s) . ' s';

Channel

Co\run(function(){  
//使用Channel進(jìn)行協(xié)程間通訊  
$chan = new Swoole\Coroutine\Channel(1);  
Swoole\Coroutine::create(function () use ($chan) {    
for($i = 0; $i < 100000; $i++) { co::sleep(1.0); $chan->push(['rand' => rand(1000, 9999), 'index' => $i]);      
echo "$i\n";    
}  
});  
Swoole\Coroutine::create(function () use ($chan) {    
while(1) {      
$data = $chan->pop();      
var_dump($data);    
}  
});});

Swoole 特性

Swoole是使用C/C++語言編寫的，提供了異步多線程服務(wù)器、異步TCP/UDP網(wǎng)絡(luò)客戶端、異步MySQL、異步Redis、數(shù)據(jù)庫連接池、AsyncTask、消息隊列、毫秒定時器、異步文件讀寫、異步DNS查詢等功能。此外，Swoole還內(nèi)置了Http/WebSocket服務(wù)器端/客戶端以及Http2.0服務(wù)器端。

除了支持異步IO，Swoole還為PHP多進(jìn)程模式設(shè)計了并發(fā)數(shù)據(jù)結(jié)構(gòu)和IPC通信機制，大大簡化了多進(jìn)程并發(fā)編程的工作。其中包括并發(fā)原子計數(shù)器、并發(fā)HashTable、Channel、Lock、進(jìn)程間通信IPC等功能特性。

Swoole4.0引入了類似Go語言的協(xié)程，可以使用完全同步的代碼實現(xiàn)異步程序。在編寫PHP代碼時無需額外增加任何關(guān)鍵詞，底層會自動進(jìn)行協(xié)程調(diào)度，實現(xiàn)異步IO。