使用纯php构建一个简单的PHP服务器

使用原生PHP构建一个简单的PHPWeb服务器

1.目录机构

webserver
    --src
        -- Response.php
        -- Server.php
        -- Request.php
    -- vendor
    -- Server.php
    -- composer.json

2. 使用comoposer构建自动加载

编辑`comooser.json`文件

{
    "autoload": {
        "psr-4": {
            "Icarus\\Station\\PHPServer\\": "src/"
        }
    }
}

使用PSR-4自动加载方式构建自动加载

3. 编写 Server文件

该文件作为启动文件，使用以下命令 php Server 8080 启动服务

<?php

use Icarus\Station\PHPServer\Server;
use Icarus\Station\PHPServer\Request;
use Icarus\Station\PHPServer\Response;

array_shift($argv);

//获取端口号
if (empty($argv)) {
    $port = 80;
}else {
    $port = (int)array_shift($argv);
}

require_once "./vendor/autoload.php";

$server = new Server("127.0.0.1",$port);

$server->listen(function(Request $request){
    return new Response("Hello World!");
});

4. 编写Response.php

该类实现对请求的响应

<?php

namespace Icarus\Station\PHPServer;

class Response
{
    protected static $statusCodes = [
        100 => 'Continue',
        101 => 'Switching Protocols',

        // Success 2xx
        200 => 'OK',
        201 => 'Created',
        202 => 'Accepted',
        203 => 'Non-Authoritative Information',
        204 => 'No Content',
        205 => 'Reset Content',
        206 => 'Partial Content',

        // Redirection 3xx
        300 => 'Multiple Choices',
        301 => 'Moved Permanently',
        302 => 'Found', // 1.1
        303 => 'See Other',
        304 => 'Not Modified',
        305 => 'Use Proxy',
        // 306 is deprecated but reserved
        307 => 'Temporary Redirect',

        // Client Error 4xx
        400 => 'Bad Request',
        401 => 'Unauthorized',
        402 => 'Payment Required',
        403 => 'Forbidden',
        404 => 'Not Found',
        405 => 'Method Not Allowed',
        406 => 'Not Acceptable',
        407 => 'Proxy Authentication Required',
        408 => 'Request Timeout',
        409 => 'Conflict',
        410 => 'Gone',
        411 => 'Length Required',
        412 => 'Precondition Failed',
        413 => 'Request Entity Too Large',
        414 => 'Request-URI Too Long',
        415 => 'Unsupported Media Type',
        416 => 'Requested Range Not Satisfiable',
        417 => 'Expectation Failed',

        // Server Error 5xx
        500 => 'Internal Server Error',
        501 => 'Not Implemented',
        502 => 'Bad Gateway',
        503 => 'Service Unavailable',
        504 => 'Gateway Timeout',
        505 => 'HTTP Version Not Supported',
        509 => 'Bandwidth Limit Exceeded'
    ];

    protected $status = 200;
    protected $body = '';
    protected $headers = [];

    public function __construct($body, $status = null)
    {
        if (!is_null($status)) {
            $this->status = $status;
        }
        $this->body = $body;
        $this->header('Date', gmdate('D, d M Y H:i:s T'));
        $this->header('Content-Type', 'text/html; charset=utf-8');
        $this->header('Server', 'PHPServer/1.0.0');
    }

    public function header($key, $val)
    {
        $this->headers[ucwords($key)] = $val;
    }

    public function buildHeaderString()
    {
        $lines = [];
        $lines[] = "HTTP/1.1 " . $this->status . " " . static::$statusCodes[$this->status];

        foreach ($this->headers as $key => $value) {
            $lines[] = $key . ": " . $value;
        }

        return implode(" \r\n", $lines) . "\r\n\r\n";
    }

    public static function error($statusCode)
    {
        header(self::$statusCodes[$statusCode], '', $statusCode);
    }

    public function __toString()
    {
        return $this->buildHeaderString() . $this->body;
    }
}

5. 编写Request.php

该类主要实现请求的解析(暂时为GET请求)

<?php

namespace Icarus\Station\PHPServer;

class Request
{
    protected $uri = '';
    protected $method = '';
    protected $params = [];
    protected $headers = [];

    public function __construct($method, $uri, $headers)
    {
        $this->method = strtolower($method);
        $this->headers = $headers;
        list($this->uri, $param) = explode('?', $uri);
        parse_str($param, $this->params);
    }

    public function method()
    {
        return $this->method;
    }

    public function headers($key, $default = null)
    {
        if (isset($this->headers[$key])) {
            $default = $this->headers[$key];
        }
        return $default;
    }

    public function uri()
    {
        return $this->uri;
    }

    public function params($key, $default = null)
    {
        if (isset($this->params[$key])) {
            $default = $this->params($key);
        }
        return $default;
    }

    public static function withHeaderString($data)
    {
        $headers = explode("\n", $data);
        list($method, $uri) = explode(" ", array_shift($headers));
        $header = [];
        foreach ($headers as $value) {
            $value = trim($value);
            if (strpos($value, ":") !== false) {
                list($key, $value) = explode(":", $value);
                $header[$key] = $value;
            }
        }
        return new static($method, $uri, $header);
    }

    public function __toString()
    {
        return json_encode($this->headers);
    }
}

6.编写Server.php

该模块主要实现对socket的封装。

<?php

namespace Icarus\Station\PHPServer;

class Server
{

    protected $host = null;
    protected $port = null;
    protected $socket = null;

    public function __construct($host, $port)
    {
        $this->host = $host;
        $this->port = $port;
        $this->createSocket();
        $this->bind();
    }

    protected function createSocket()
    {
        $this->socket = socket_create(AF_INET, SOCK_STREAM, 0);
    }

    protected function bind()
    {
        if (!socket_bind($this->socket,$this->host, $this->port)) {
            throw  new \Exception("未能绑定socket: " . $this->host . $this->port . socket_strerror(socket_last_error()));
        }

    }

    public function listen(callable $callback)
    {
        while (true) {
            socket_listen($this->socket);
            if (!$client = socket_accept($this->socket)) {
                socket_close($client);
                continue;
            }
            $data = socket_read($client, 1024);
            $request = Request::withHeaderString($data);
            $response = call_user_func($callback, $request);
            if (!$response | !$response instanceof Response) {
                $response = Response::error(404);
            }
            $response = (string)$response;
            socket_write($client,$response,strlen($response));
            socket_close($client);
        }
    }
}

7. 使用

1. 进入到项目目录
2. 执行` php Server 8080`
3. 另起一个终端，执行 `curl "http://127.0.0.1:8080`
4. 显示 `Hello World!`

8. 总结

该demo使用socket来实现一个简单的webserver，但是由于php不支持多线程的的特性（其实也能实现，不过需要安装pthreads扩展），还是不适合开发webserver，此demo主要用来学习webserver的概念。

此demo参考了http://station.clancats.com/writing-a-webserver-in-pure-php/的讲解及实现。