restful设计架构，例子

/**
 * Project: imooc-restful
 * User: xialei
 * Date: 2016/9/18 0018
 * Time: 9:35
 */
require_once __DIR__ . '/../handler/User.php';
require_once __DIR__ . '/../handler/Article.php';
require_once __DIR__ . '/../handler/MyHttpException.php';

class Bridge
{
    /**
     * @var User
     */
    private $user;
    /**
     * @var Article
     */
    private $article;
    /**
     * @var string 请求方法
     */
    private $method;
    /**
     * @var string 请求实体
     */
    private $entity;

    /**
     * @var integer ID
     */
    private $id;

    /**
     * @var array 允许请求的实体类
     */
    private $allowEntities = ['users', 'articles'];

    private $allowMethods = ['GET', 'POST', 'PUT', 'OPTIONS', 'HEAD', 'DELETE'];

    /**
     * Bridge constructor.
     */
    public function __construct()
    {
        $pdo = require_once __DIR__ . '/../db.php';
        $this->user = new User($pdo);
        $this->article = new Article($pdo);
        $this->setupRequestMethod();
        $this->setupEntity();
    }

    /**
     * 初始化实体
     */
    private function setupEntity()
    {
        $pathinfo = $_SERVER['PATH_INFO'];
        if (empty($pathinfo))
        {
            static::sendHttpStatus(400);
        }
        $params = explode('/', $pathinfo);
        $this->entity = $params[1];
        if (!in_array($this->entity, $this->allowEntities))
        {
            //实体不存在
            static::sendHttpStatus(404);
        }
        if (!empty($params[2]))
        {
            $this->id = $params[2];
        }
    }

    /**
     * 发送HTTP响应状态码
     * @param $code
     * @param string $error
     * @param array|null $data
     * @internal param null $message
     */
    static function sendHttpStatus($code, $error = '', $data = null)
    {
        static $_status = array(
            // Informational 1xx
            100 => 'Continue',
            101 => 'Switching Protocols',
            // Success 2xx
            200 => 'OK',
            201 => 'Created',
            202 => 'Accepted',
            203 => 'Non-Authoritative Information',
            204 => 'No Content',
            205 => 'Reset Content',
            206 => 'Partial Content',
            // Redirection 3xx
            300 => 'Multiple Choices',
            301 => 'Moved Permanently',
            302 => 'Found',  // 1.1
            303 => 'See Other',
            304 => 'Not Modified',
            305 => 'Use Proxy',
            // 306 is deprecated but reserved
            307 => 'Temporary Redirect',
            // Client Error 4xx
            400 => 'Bad Request',
            401 => 'Unauthorized',
            402 => 'Payment Required',
            403 => 'Forbidden',
            404 => 'Not Found',
            405 => 'Method Not Allowed',
            406 => 'Not Acceptable',
            407 => 'Proxy Authentication Required',
            408 => 'Request Timeout',
            409 => 'Conflict',
            410 => 'Gone',
            411 => 'Length Required',
            412 => 'Precondition Failed',
            413 => 'Request Entity Too Large',
            414 => 'Request-URI Too Long',
            415 => 'Unsupported Media Type',
            416 => 'Requested Range Not Satisfiable',
            417 => 'Expectation Failed',
            422 => 'Unprocessable Entity',
            // Server Error 5xx
            500 => 'Internal Server Error',
            501 => 'Not Implemented',
            502 => 'Bad Gateway',
            503 => 'Service Unavailable',
            504 => 'Gateway Timeout',
            505 => 'HTTP Version Not Supported',
            509 => 'Bandwidth Limit Exceeded'
        );
        if (isset($_status[$code]))
        {
            header('HTTP/1.1 ' . $code . ' ' . $_status[$code]);
            header('Content-Type:application/json;charset=utf-8');
            if ($code == 200) //2xx状态码
            {
                echo json_encode($data, JSON_UNESCAPED_UNICODE);
            }
            else if ($code == 204)
            {
                //无响应体
            }
            else
            {
                if (empty($error))
                {
                    $error = $_status[$code];
                }
                echo json_encode(['error' => $error], JSON_UNESCAPED_UNICODE);
            }
        }
        exit(0);
    }

    /**
     * 初始化请求方法
     */
    private function setupRequestMethod()
    {
        $this->method = $_SERVER['REQUEST_METHOD'];
        if (!in_array($this->method, $this->allowMethods))
        {
            //请求方法不被允许
            static::sendHttpStatus(405);
        }
    }

    /**
     * 处理请求
     */
    public function handle()
    {
        try
        {
            if ($this->entity == 'users')
            {
                $this->handleUser();
            }
            if ($this->entity == 'articles')
            {
                $this->handleArticle();
            }
        }
        catch (MyHttpException $e)
        {
            static::sendHttpStatus($e->getStatusCode(), $e->getMessage());
        }
    }

    /**
     * 获取请求体
     * @return mixed|null
     */
    private function getBodyParams()
    {
        $raw = file_get_contents('php://input');
        if (empty($raw))
        {
            return [];
        }
        return json_decode($raw, true);
    }

    private function getBodyParam($name, $defaultValue = null)
    {
        $data = $this->getBodyParams();
        return isset($data[$name]) ? $data[$name] : $defaultValue;
    }

    /**
     * 要求认证
     * @return bool|array
     * @throws MyHttpException
     */
    private function requestAuth()
    {
        if (!empty($_SERVER['PHP_AUTH_USER']) && !empty($_SERVER['PHP_AUTH_PW']))
        {
            try
            {
                $user = $this->user->login($_SERVER['PHP_AUTH_USER'], $_SERVER['PHP_AUTH_PW']);
                return $user;
            }
            catch (MyHttpException $e)
            {
                if ($e->getStatusCode() != 422)
                {
                    throw $e;
                }
            }
        }
        header("WWW-Authenticate:Basic realm='Private'");
        header('HTTP/1.0 401 Unauthorized');
        print "You are unauthorized to enter this area.";
        exit(0);
    }

    /**
     * 处理访问用户的请求
     */
    private function handleUser()
    {
        if ($this->method == 'GET')
        {
            if (empty($this->id))
            {
                //客户端需要获取所有用户的信息，访问有效，但是无权限
                throw new MyHttpException(403);
            }
            static::sendHttpStatus(200, null, $this->user->view($this->id));
        }
        else if ($this->method == 'POST')
        {
            $data = $this->getBodyParams();
            if (empty($data['username']))
            {
                throw new MyHttpException(422, '用户名不能为空');
            }
            if (empty($data['password']))
            {
                throw new MyHttpException(422, '密码不能为空');
            }
            static::sendHttpStatus(200, null, $this->user->register($data['username'], $data['password']));
        }
        else if ($this->method == 'PUT')
        {
            if (empty($this->id))
            {
                throw new MyHttpException(400);
            }
            $params = $this->getBodyParams();
            if (empty($params) || empty($params['password']))
            {
                throw new MyHttpException(422, '密码不能为空');
            }
            //检测认证参数
            $user = $this->requestAuth();
            $result = $this->user->update($user['userId'], $params['password']);
            static::sendHttpStatus(200, null, $result);
        }
        else
        {
            throw new MyHttpException(405);
        }
    }

    private function getQueryParam($name, $defaultValue = null)
    {
        return isset($_GET[$name]) ? $_GET[$name] : $defaultValue;
    }

    /**
     * 处理访问文章的请求
     */
    private function handleArticle()
    {
        if ($this->method == 'GET')
        {
            $user = $this->requestAuth();
            if (empty($this->id))
            {
                $list = $this->article->all($user['userId'], $this->getQueryParam('page', 1), $this->getQueryParam('size', 10));
                self::sendHttpStatus(200, null, $list);
            }
            self::sendHttpStatus(200, null, $this->article->view($this->id));
        }
        else if ($this->method == 'POST')
        {
            $user = $this->requestAuth();
            $data = $this->getBodyParams();
            if (empty($data['title']))
            {
                throw new MyHttpException(422, '标题不能为空');
            }
            if (empty($data['content']))
            {
                throw new MyHttpException(422, '内容不能为空');
            }
            $article = $this->article->create($data['title'], $data['content'], $user['userId']);
            static::sendHttpStatus(200, null, $article);
        }
        else if ($this->method == 'PUT')
        {
            if (empty($this->id))
            {
                throw new MyHttpException(400);
            }
            $user = $this->requestAuth();
            $data = $this->getBodyParams();
            $title = isset($data['title']) ? $data['title'] : null;
            $content = isset($data['content']) ? $data['content'] : null;
            $article = $this->article->update($this->id, $title, $content, $user['userId']);
            static::sendHttpStatus(200, null, $article);
        }
        else if ($this->method == 'DELETE')
        {
            if (empty($this->id))
            {
                throw new MyHttpException(400);
            }
            $user = $this->requestAuth();
            $this->article->delete($this->id, $user['userId']);
            static::sendHttpStatus(204, null, null);
        }
    }
}


$bridge = new Bridge();
$bridge->handle();

转于：https://www.imooc.com/video/14365 ,微信xialeistudio

　　完整代码：https://github.com/xialeistudio/imooc-restful