.
/**
* REST web service implementation classes and methods.
*
* @package webservice
* @copyright 2009 Moodle Pty Ltd (http://moodle.com)
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
require_once("$CFG->dirroot/webservice/lib.php");
/**
* REST service server implementation.
* @author Petr Skoda (skodak)
*/
class webservice_rest_server extends webservice_base_server {
/** @property string $alt return method (XML / JSON) */
protected $restformat;
/**
* Contructor
*/
public function __construct($authmethod, $restformat = 'xml') {
parent::__construct($authmethod);
$this->wsname = 'rest';
$this->restformat = ($restformat != 'xml' && $restformat != 'json')?'xml':$restformat; //sanity check, we accept only xml or json
}
/**
* This method parses the $_POST and $_GET superglobals and looks for
* the following information:
* 1/ user authentication - username+password or token (wsusername, wspassword and wstoken parameters)
* 2/ function name (wsfunction parameter)
* 3/ function parameters (all other parameters except those above)
*
* @return void
*/
protected function parse_request() {
//Get GET and POST paramters
$methodvariables = array_merge($_GET,$_POST);
if ($this->authmethod == WEBSERVICE_AUTHMETHOD_USERNAME) {
$this->username = isset($methodvariables['wsusername']) ? $methodvariables['wsusername'] : null;
unset($methodvariables['wsusername']);
$this->password = isset($methodvariables['wspassword']) ? $methodvariables['wspassword'] : null;
unset($methodvariables['wspassword']);
$this->functionname = isset($methodvariables['wsfunction']) ? $methodvariables['wsfunction'] : null;
unset($methodvariables['wsfunction']);
$this->parameters = $methodvariables;
} else {
$this->token = isset($methodvariables['wstoken']) ? $methodvariables['wstoken'] : null;
unset($methodvariables['wstoken']);
$this->functionname = isset($methodvariables['wsfunction']) ? $methodvariables['wsfunction'] : null;
unset($methodvariables['wsfunction']);
$this->parameters = $methodvariables;
}
}
/**
* Send the result of function call to the WS client
* formatted as XML document.
* @return void
*/
protected function send_response() {
//Check that the returned values are valid
try {
if ($this->function->returns_desc != null) {
$validatedvalues = external_api::clean_returnvalue($this->function->returns_desc, $this->returns);
} else {
$validatedvalues = null;
}
} catch (Exception $ex) {
$exception = $ex;
}
if (!empty($exception)) {
$response = $this->generate_error($exception);
} else {
//We can now convert the response to the requested REST format
if ($this->restformat == 'json') {
$response = json_encode($validatedvalues);
} else {
$response = ''."\n";
$response .= ''."\n";
$response .= self::xmlize_result($this->returns, $this->function->returns_desc);
$response .= ''."\n";
}
}
$this->send_headers();
echo $response;
}
/**
* Send the error information to the WS client
* formatted as XML document.
* Note: the exception is never passed as null,
* it only matches the abstract function declaration.
* @param exception $ex
* @return void
*/
protected function send_error($ex=null) {
$this->send_headers();
echo $this->generate_error($ex);
}
/**
* Build the error information matching the REST returned value format (JSON or XML)
* @param exception $ex
* @return string the error in the requested REST format
*/
protected function generate_error($ex) {
if ($this->restformat == 'json') {
$errorobject = new stdClass;
$errorobject->exception = get_class($ex);
$errorobject->message = $ex->getMessage();
if (debugging() and isset($ex->debuginfo)) {
$errorobject->debuginfo = $ex->debuginfo;
}
$error = json_encode($errorobject);
} else {
$error = ''."\n";
$error .= ''."\n";
$error .= ''.htmlspecialchars($ex->getMessage(), ENT_COMPAT, 'UTF-8').''."\n";
if (debugging() and isset($ex->debuginfo)) {
$error .= ''.htmlspecialchars($ex->debuginfo, ENT_COMPAT, 'UTF-8').''."\n";
}
$error .= ''."\n";
}
return $error;
}
/**
* Internal implementation - sending of page headers.
* @return void
*/
protected function send_headers() {
if ($this->restformat == 'json') {
header('Content-type: application/json');
} else {
header('Content-Type: application/xml; charset=utf-8');
header('Content-Disposition: inline; filename="response.xml"');
}
header('Cache-Control: private, must-revalidate, pre-check=0, post-check=0, max-age=0');
header('Expires: '. gmdate('D, d M Y H:i:s', 0) .' GMT');
header('Pragma: no-cache');
header('Accept-Ranges: none');
}
/**
* Internal implementation - recursive function producing XML markup.
* @param mixed $returns
* @param $desc
* @return unknown_type
*/
protected static function xmlize_result($returns, $desc) {
if ($desc === null) {
return '';
} else if ($desc instanceof external_value) {
if (is_bool($returns)) {
// we want 1/0 instead of true/false here
$returns = (int)$returns;
}
if (is_null($returns)) {
return ''."\n";
} else {
return ''.htmlspecialchars($returns, ENT_COMPAT, 'UTF-8').''."\n";
}
} else if ($desc instanceof external_multiple_structure) {
$mult = ''."\n";
if (!empty($returns)) {
foreach ($returns as $val) {
$mult .= self::xmlize_result($val, $desc->content);
}
}
$mult .= ''."\n";
return $mult;
} else if ($desc instanceof external_single_structure) {
$single = ''."\n";
foreach ($desc->keys as $key=>$subdesc) {
$single .= ''.self::xmlize_result($returns[$key], $subdesc).''."\n";
}
$single .= ''."\n";
return $single;
}
}
}
/**
* REST test client class
*/
class webservice_rest_test_client implements webservice_test_client_interface {
/**
* Execute test client WS request
* @param string $serverurl
* @param string $function
* @param array $params
* @return mixed
*/
public function simpletest($serverurl, $function, $params) {
return download_file_content($serverurl.'&wsfunction='.$function, null, $params);
}
}