JSONServer.php

<?php
/**
 * JSON server
 */
class JSONServer
{
    /**
     * @var the service object instance
     */
    private $obj;

    /**
     * Create a new JSONServer instance
     *
     * @param $obj object the object to invoke service methods on
     */
    public function __construct(RemoteService $obj)
    {
        $this->obj = $obj;
    }

    /**
     * Handle a JSON POST request
     */
    public function handle()
    {

        //print_r(get_class_methods($this->obj));
        //die('i died');

        $post = file_get_contents('php://input');
        //error_log($post);
        $response = array();
        try {
            if (empty($post)) {
                throw new JSONFault(JSONFault::BAD_REQUEST, 'empty request.');
            }
            $request = json_decode($post, true);
            if (empty($request['method'])) {
                throw new JSONFault(JSONFault::BAD_REQUEST, 'method not specified.');
            }
            if (!method_exists($this->obj, $request['method'])) {
                throw new JSONFault(JSONFault::METHOD_NOT_DEFINED,
                    "the specified method, {$request['method']}, is not defined.");
            }

            $ref = new ReflectionMethod(get_class($this->obj), $request['method']);
            $params = array();
            $arrp = $ref->getParameters();
            
            // function parameters must be ordered
            $missing = array();
            foreach ($arrp as $param) {
                $n = $param->getName();
                if (isset($request['params'][$n])) {
                    $params[$n] = $request['params'][$n];
                } else if ($param->isDefaultValueAvailable()) {
                    $params[$n] = $param->getDefaultValue();
                } else {
                    $missing[] = $n;
                }
            }

            if (!empty($missing)) {
                $msg = "missing required parameter" . ((count($missing) > 1) ? 's: ' . implode($missing, ', ') : ": $missing[0]");
                throw new JSONFault(JSONFault::MISSING_PARAM, $msg);
            }

            $this->obj->preProcessCallback();
            $response = array(
                'response' => $ref->invokeArgs($this->obj, $params),
                'errors' => 0,
                'errorMsg' => '',
            );
        } catch (JSONFault $f) {
            error_log("JSONFault code {$f->getCode()} handling {$request['method']}: {$f->getMessage()}", E_USER_NOTICE);
            $response = array(
                'response' => null,
                'errors' => $f->getCode(),
                'errorMsg' => $f->getMessage(),
            );
        }
        die(json_encode($response));
    }
}