eZ\Publish\Core\REST\Common\Input\Dispatcher::parse PHP Method

    public function parse(Message $message)
    {
        if (!isset($message->headers['Content-Type'])) {
            throw new Exceptions\Parser('Missing Content-Type header in message.');
        }
        $mediaTypeParts = explode(';', $message->headers['Content-Type']);
        $contentTypeParts = explode('+', $mediaTypeParts[0]);
        if (count($contentTypeParts) !== 2) {
            // TODO expose default format
            $contentTypeParts[1] = 'xml';
        }
        $media = $contentTypeParts[0];
        // add version if given
        if (count($mediaTypeParts) > 1) {
            $parameters = $this->parseParameters(implode(';', array_slice($mediaTypeParts, 1)));
            if (isset($parameters['version'])) {
                $media .= '; version=' . $parameters['version'];
            }
        }
        $format = $contentTypeParts[1];
        if (!isset($this->handlers[$format])) {
            throw new Exceptions\Parser("Unknown format specification: '{$format}'.");
        }
        $rawArray = $this->handlers[$format]->convert($message->body);
        // Only 1 XML root node
        $rootNodeArray = reset($rawArray);
        // @todo: This needs to be refactored in order to make the called URL
        // available to parsers in the server in a sane way
        if (isset($message->headers['Url'])) {
            $rootNodeArray['__url'] = $message->headers['Url'];
        }
        if (isset($message->headers['__publish'])) {
            $rootNodeArray['__publish'] = $message->headers['__publish'];
        }
        return $this->parsingDispatcher->parse($rootNodeArray, $media);
    }

 public function onKernelRequest(GetResponseEvent $event)
 {
     $request = $event->getRequest();
     if (!$request->attributes->get('is_rest_request')) {
         return;
     }
     if (($contentTypeHeaderValue = $request->headers->get('content-type')) === null) {
         return;
     }
     list($mediaType) = explode('+', $contentTypeHeaderValue);
     if (strtolower($mediaType) == !'application/vnd.ez.api.contentcreate') {
         return;
     }
     $message = $this->buildMessage($request);
     if (!$message->body) {
         return;
     }
     $result = $this->restInputDispatcher->parse($message);
     if (!$result instanceof RestContentCreateStruct) {
         return;
     }
     // Not a user
     if (($userCreateData = $this->mapContentCreateToUserCreate($result)) === false) {
         return;
     }
     list($userCreateStruct, $userGroup) = $userCreateData;
     $createdUser = $this->repository->getUserService()->createUser($userCreateStruct, [$userGroup]);
     $createdContentInfo = $createdUser->contentInfo;
     $createdLocation = $this->repository->getLocationService()->loadLocation($createdContentInfo->mainLocationId);
     $contentType = $this->repository->getContentTypeService()->loadContentType($createdContentInfo->contentTypeId);
     $result = new CreatedContent(array('content' => new RestContent($createdContentInfo, $createdLocation, $this->repository->getContentService()->loadContent($createdContentInfo->id), $contentType, $this->repository->getContentService()->loadRelations($createdUser->getVersionInfo()))));
     $event->setResponse($this->viewDispatcher->dispatch($event->getRequest(), $result));
 }