php实现的一个简单json rpc框架实例

json rpc 是一种以json为消息格式的远程调用服务，它是一套允许运行在不同操作系统、不同环境的程序实现基于Internet过程调用的规范和一系列的实现。这种远程过程调用可以使用http作为传输协议，也可以使用其它传输协议，传输的内容是json消息体。

下面我们code一套基于php的rpc框架，此框架中包含rpc的服务端server，和应用端client；

（一）PHP服务端RPCserver jsonRPCServer.php

class jsonRPCServer {

    /**

     *处理一个request类，这个类中绑定了一些请求参数

     * @param object $object

     * @return boolean

     */

    public static function handle($object) {

       // 判断是否是一个rpc json请求

        if ($_SERVER['REQUEST_METHOD'] != 'POST' || empty($_SERVER['CONTENT_TYPE'])

            ||$_SERVER['CONTENT_TYPE'] != 'application/json') {

            return false;

        }

        // reads the input data

        $request = json_decode(file_get_contents('php://input'),true);

        // 执行请求类中的接口

        try {

            if ($result = @call_user_func_array(array($object,$request['method']),$request['params'])) {

                $response = array ( 'id'=> $request['id'],'result'=> $result,'error'=> NULL );

            } else {

                $response = array ( 'id'=> $request['id'], 'result'=> NULL,

                                        'error' => 'unknown method or incorrect parameters' );}

        } catch (Exception $e) {

            $response = array ('id' => $request['id'],'result' => NULL, 'error' =>$e->getMessage());

        }

       // json 格式输出

        if (!empty($request['id'])) { // notifications don't want response

            header('content-type: text/javascript');

            echo json_encode($response);

        }

        return true;

    }

}

(二)Rpc客户端，jsonRPCClient.php

<?php

/*

 */

class jsonRPCClient {
    private $debug;

    private $url;

    // 请求id

    private $id;

    private $notification = false;

    /**

     * @param $url

     * @param bool $debug

     */

    public function __construct($url,$debug = false) {

        // server URL

        $this->url = $url;

        // proxy

        empty($proxy) ? $this->proxy = '' : $this->proxy = $proxy;

        // debug state

        empty($debug) ? $this->debug = false : $this->debug = true;

        // message id

        $this->id = 1;

    }
    /**

     *

     * @param boolean $notification

     */

    public function setRPCNotification($notification) {

        empty($notification) ? $this->notification = false  : $this->notification = true;

    }
    /**

     * @param $method

     * @param $params

     * @return bool

     * @throws Exception

     */

    public function __call($method,$params) {

        // 检验request信息

        if (!is_scalar($method)) {

            throw new Exception('Method name has no scalar value');

        }

        if (is_array($params)) {

            $params = array_values($params);

        } else {

            throw new Exception('Params must be given as array');

        }
        if ($this->notification) {

            $currentId = NULL;

        } else {

            $currentId = $this->id;

        }
       // 拼装成一个request请求

        $request = array(  'method' => $method,  'params' => $params,'id' => $currentId);

        $request = json_encode($request);

        $this->debug && $this->debug.='***** Request *****'."\n".$request."\n".'***** End Of request *****'."\n\n";

        $opts = array ('http' => array (

                                    'method'  => 'POST',

                                    'header'  => 'Content-type: application/json',

                                    'content' => $request

        ));

        //  关键几部

        $context  = stream_context_create($opts);

  if ( $result = file_get_contents($this->url, false, $context)) {

            $response = json_decode($result,true);

  } else {

   throw new Exception('Unable to connect to '.$this->url);

  }

        // 输出调试信息

        if ($this->debug) {

            echo nl2br(($this->debug));

        }

        // 检验response信息

        if (!$this->notification) {

            // check

            if ($response['id'] != $currentId) {

                throw new Exception('Incorrect response id (request id: '.$currentId.', response id: '.$response['id'].')');

            }

            if (!is_null($response['error'])) {

                throw new Exception('Request error: '.$response['error']);

            }

            return $response['result'];
        } else {

            return true;

        }

    }

}

?>

(三) 应用实例
（1）服务端 server.php

<?php

require_once 'jsonRPCServer.php';

// member 为测试类

require 'member.php';

// 服务端调用

$myExample = new member();

// 注入实例

jsonRPCServer::handle($myExample)

 or print 'no request';

?>

（2）测试类文件，member.php

class member{

    public function getName(){

        return 'hello word ' ;  // 返回字符串

    }

}

（3）客户端 client.php

require_once 'jsonRPCClient.php';
$url = 'http://localhost/rpc/server.php';

$myExample = new jsonRPCClient($url);
// 客户端调用

try {

 $name = $myExample->getName();

    echo $name ;

} catch (Exception $e) {

 echo nl2br($e->getMessage()).'<br />'."\n";

}