使用php(非swoole)实现tcp/http服务器。
php内置的stream系列函数 和 socket扩展提供了对网络编程的支持。socket扩展需要在编译时通过配置--enable-sockets开启，而strem系列函数则完全是php核心内置的函数。php社区中的workman框架底层就是基于stream函数来实现的。以下代码通过stream系列函数演示php如何实现简单的tcp/http等服务器
1:单进程阻塞模式
socket = @stream_socket_server($address, $errNo, $errMessage);
if (!is_resource($this->socket)) {
throw new InvalidArgumentException("参数异常:" . $errMessage);
}
}
public function isHttp(bool $bool): self
{
$this->isHttp = $bool;
return $this;
}
/**
* 启动服务器
*/
public function run()
{
while (true) {
$conn = @stream_socket_accept($this->socket);
if ($conn) {
if ($this->isHttp) {
//http server
$data = "Hello World";
$response = "HTTP/1.1 200 OK\r\n";
$response .= "Content-Type: text/html;charset=UTF-8\r\n";
$response .= "Server: MyServer1\r\n";
$response .= "Content-length: " . strlen($data) . "\r\n\r\n";
$response .= $data;
fwrite($conn, $response);
fclose($conn);
} else {
// tcp server
while ($message = fread($conn, 1024)) {
// 主动退出
if (trim($message) == 'quit') {
echo "close\n";
fclose($conn);
break;
}
echo 'I have received that : ' . $message;
fwrite($conn, "OK\n");
}
}
}
}
}
}
$server = new Server("0.0.0.0:2345");
// 启动 tcp 服务器
$server->run();
// 启动 http服务器
//$server->isHttp(true)->run();http服务浏览器访问http://127.0.0.1:2345/看可以看到输出hello world
tcp服器通过telnet进行测试
由于连接和read都是阻塞的,此时一次只能处理一个请求,只能当当前请求处理结束后才能处理下一个请求，不具备并发能力。
2：多进程改造
socket = @stream_socket_server($address, $errNo, $errMessage);
if (!is_resource($this->socket)) {
throw new InvalidArgumentException("参数异常:" . $errMessage);
}
}
public function isHttp(bool $bool): self
{
$this->isHttp = $bool;
return $this;
}
/**
* 启动服务器
*/
public function run()
{
while (true) {
$conn = @stream_socket_accept($this->socket);
if ($conn) {
if ($this->isHttp) {
if (pcntl_fork() == 0) {
//http server
$data = "Hello World";
$response = "HTTP/1.1 200 OK\r\n";
$response .= "Content-Type: text/html;charset=UTF-8\r\n";
$response .= "Server: MyServer1\r\n";
$response .= "Content-length: " . strlen($data) . "\r\n\r\n";
$response .= $data;
fwrite($conn, $response);
fclose($conn);
exit;
}
} else {
// tcp server
if (pcntl_fork() == 0) {
while ($message = fread($conn, 1024)) {
echo 'I have received that : ' . $message;
fwrite($conn, "OK\n");
}
exit;
}
}
}
}
}
}
$server = new Server("0.0.0.0:2345");
// 启动 tcp 服务器
$server->run();
// 启动 http服务器
//$server->isHttp(true)->run();此时，由于通过子进程处理原本阻塞的read函数，所以主进程可以accept新的请求，提高并发能力。
由于创建进程/线程会带来很多新的问题，比如系统开销增大等，所以，这种方法基本不会在生产环境中使用。
3：IO多路复用(select方式)
socket = @stream_socket_server($address, $errNo, $errMessage);
if (!is_resource($this->socket)) {
throw new InvalidArgumentException("参数异常:" . $errMessage);
}
// stream_set_blocking 设置非阻塞io
stream_set_blocking($this->socket, false);
// 添加当前监听的socket
$this->socketList[(int)$this->socket] = $this->socket;
}
public function isHttp(bool $bool): self
{
$this->isHttp = $bool;
return $this;
}
/**
* 启动服务器
*/
public function run()
{
while (true) {
$read = $this->socketList;
$write = $except = [];
//阻塞监听 设置null阻塞监听
$count = @stream_select($read, $write, $except, null);
if ($count) {
foreach ($read as $k => $v) {
if ($v == $this->socket) {
// connect success
// accept Connection
@$conn = stream_socket_accept($this->socket, null, $remote_address);
echo "connect fd:" . $k . PHP_EOL;
$this->socketList[(int)$conn] = $conn;
} else {
//receive
if ($this->isHttp) {
$this->receiveHttp($v);
} else {
$this->receiveTcp($v);
}
}
}
}
}
}
protected function receiveHttp($stream)
{
$buffer = fread($stream, 1024);
if (empty($buffer) && (feof($stream) || !is_resource($stream))) {
fclose($stream);
unset($this->socketList[(int)$stream]);
echo "退出成功" . PHP_EOL;
return;
}
//http server
$data = "Hello World";
$response = "HTTP/1.1 200 OK\r\n";
$response .= "Content-Type: text/html;charset=UTF-8\r\n";
$response .= "Server: MyServer1\r\n";
$response .= "Content-length: " . strlen($data) . "\r\n\r\n";
$response .= $data;
fwrite($stream, $response);
}
/**
* 处理tcp请求
*/
private function receiveTcp($stream)
{
$buffer = fread($stream, 1024);
if (feof($stream) || !is_resource($stream)) {
unset($this->socketList[(int)$stream]);
fclose($stream);
echo "退出成功" . PHP_EOL;
return;
}
echo 'onReceive ' . $buffer . " ->" . $stream . PHP_EOL;
$message = 'I have received that : ' . $buffer;
fwrite($stream, "{$message}");
}
}
$server = new Server("0.0.0.0:2345");
// 启动 tcp 服务器
//$server->run();
// 启动 http服务器
$server->isHttp(true)->run();通过IO多路复用是目前解决高并发(C10k)问题的主要思路。
通过stream_select函数调用操作系统提供的select方法，将接收到的文件描述符号传递给操作系统底层，由操作系统遍历并且返回需要处理的文件描述符号，从而不需要在应用层面一直阻塞，提高并发能力。
4：IO多路费用(poll epoll)
由于select方法存在种种问题，比如性能差，数量限制等。应对小规模并发没有问题，但是大规模并发就显得捉襟见肘，这个时候就需要poll，epoll(推荐)方法实现多路复用。
具体到php里面需要安装event或者libevent扩展，详细代码可以参考workman源码，这里不再展示。
实例代码
参考：
- https://www.php.net/manual/zh... (php支持的Socket Transports)
- https://www.php.net/manual/zh...
- https://www.php.net/manual/zh...