Proyectos de Subversion Moodle

<?php declare(strict_types=1);

namespace EduSharingApiClient;

use Exception;

use JsonException;

/**

 * Class EduSharingNodeHelper

 *

 * @author Torsten Simon  <simon@edu-sharing.net>

 * @author Marian Ziegler <ziegler@edu-sharing.net>

 */

class EduSharingNodeHelper extends EduSharingHelperAbstract

{

    private EduSharingNodeHelperConfig $config;

    public function __construct(EduSharingHelperBase $base, EduSharingNodeHelperConfig $config) {

        parent::__construct($base);

        $this->config = $config;

    }

    /**

     * creates a usage for a given node

     * The given usage can later be used to fetch this node REGARDLESS of the actual user

     * The usage gives permanent access to this node and acts similar to a license

     * In order to be able to create an usage for a node, the current user (provided via the ticket)

     * MUST have CC_PUBLISH permissions on the given node id

     * @param string $ticket

     * A ticket with the user session who is creating this usage

     * @param string $containerId

     * A unique page / course id this usage refers to inside your system (e.g. a database id of the page you include the usage)

     * @param string $resourceId

     * The individual resource id on the current page or course this object refers to

     * (you may enumerate or use unique UUID's)

     * @param string $nodeId

     * The edu-sharing node id the usage shall be created for

     * @param string|null $nodeVersion

     * Optional: The fixed version this usage should refer to

     * If you leave it empty, the usage will always refer to the latest version of the node

     * @return Usage

     * An usage element you can use with @getNodeByUsage

     * Keep all data of this object stored inside your system!

     * @throws JsonException

     * @throws Exception

     */

    public function createUsage(string $ticket, string $containerId, string $resourceId, string $nodeId, string $nodeVersion = null): Usage {

        $headers   = $this->getSignatureHeaders($ticket);

        $headers[] = $this->getRESTAuthenticationHeader($ticket);

        $curl      = $this->base->handleCurlRequest($this->base->baseUrl . '/rest/usage/v1/usages/repository/-home-', [

            CURLOPT_FAILONERROR    => false,

            CURLOPT_POST           => 1,

            CURLOPT_POSTFIELDS     => json_encode([

                'appId'       => $this->base->appId,

                'courseId'    => $containerId,

                'resourceId'  => $resourceId,

                'nodeId'      => $nodeId,

                'nodeVersion' => $nodeVersion,

            ], 512, JSON_THROW_ON_ERROR),

            CURLOPT_RETURNTRANSFER => 1,

            CURLOPT_HTTPHEADER     => $headers

        ]);

        $data = json_decode($curl->content, true, 512, JSON_THROW_ON_ERROR);

        if ((int)$curl->info['http_code'] === 403 || (!empty($data['error']) && $data['message'] === 'NO_CCPUBLISH_PERMISSION')) {

            throw new MissingRightsException("User missing publish rights.");

        }

        if (empty($data['parentNodeId']) || empty($data['nodeId'])) {

            error_log('Creating usage failed for node: ' . $nodeId . '. Returned content: ' . $curl->content);

            throw new Exception('creating usage failed: ' . $nodeId);

        }

        if ($curl->error === 0 && $curl->info['http_code'] ?? 0 === 200 && empty($data['error'])) {

            return new Usage($data['parentNodeId'], $nodeVersion, $containerId, $resourceId, $data['nodeId']);

        }

        throw new Exception('creating usage failed ' . $curl->info['http_code'] . ': ' . $data['error'] . ' ' . $data['message']);

    }

    /**

     * @DEPRECATED

     * Function getUsageIdByParameters

     *

     * Returns the id of an usage object for a given node, container & resource id of that usage

     * This is only relevant for legacy plugins which do not store the usage id and need to fetch it in order to delete an usage

     * @param string $ticket

     * A ticket with the user session who is creating this usage

     * @param string $containerId

     * A unique page / course id this usage refers to inside your system (e.g. a database id of the page you include the usage)

     * @param string $resourceId

     * The individual resource id on the current page or course this object refers to

     * (you may enumerate or use unique UUID's)

     * @return string|null

     * The id of the usage, or NULL if no usage with the given data was found

     * @throws Exception

     */

    public function getUsageIdByParameters(string $ticket, string $nodeId, string $containerId, string $resourceId): ?string {

        $headers   = $this->getSignatureHeaders($ticket);

        $headers[] = $this->getRESTAuthenticationHeader($ticket);

        $curl      = $this->base->handleCurlRequest($this->base->baseUrl . '/rest/usage/v1/usages/node/' . rawurlencode($nodeId), [

            CURLOPT_FAILONERROR    => false,

            CURLOPT_RETURNTRANSFER => 1,

            CURLOPT_HTTPHEADER     => $headers

        ]);

        $data      = json_decode($curl->content, true, 512, JSON_THROW_ON_ERROR);

        if ($curl->error === 0 && $curl->info['http_code'] ?? 0 === 200 && isset($data['usages'])) {

            foreach ($data['usages'] as $usage) {

                if ((string)$usage['appId'] === $this->base->appId && (string)$usage['courseId'] === $containerId && (string)$usage['resourceId'] === $resourceId) {

                    return isset($usage['nodeId']) ? (string)$usage['nodeId'] : null;

                }

            }

            return null;

        }

        throw new Exception('fetching usage list for course failed '

            . ($curl->info['http_code'] ?? 'unknown') . ': ' . ($data['error'] ?? 'unknown') . ' ' . ($data['message'] ?? 'unknown'));

    }

    /**

     * Function getNodeByUsage

     *

     * Loads the edu-sharing node referred by a given usage

     * @param Usage $usage

     * The usage, as previously returned by @createUsage

     * @param string $displayMode

     * The displayMode

     * This will ONLY change the content representation inside the "detailsSnippet" return value

     * @param array|null $renderingParams

     * @param string|null $userId

     * The userId can be included for tracking and statistics purposes

     * @return array

     * Returns an object containing a "detailsSnippet" representation

     * as well as the full node as provided by the REST API

     * Please refer to the edu-sharing REST documentation for more details

     * @throws JsonException

     * @throws NodeDeletedException

     * @throws UsageDeletedException

     * @throws Exception

     */

    public function getNodeByUsage(Usage $usage, string $displayMode = DisplayMode::INLINE, ?array $renderingParams = null, ?string $userId = null): array {

        $url = $this->base->baseUrl . '/rest/rendering/v1/details/-home-/' . rawurlencode($usage->nodeId);

        $url .= '?displayMode=' . rawurlencode($displayMode);

        if ($usage->nodeVersion) {

            $url .= '&version=' . rawurlencode($usage->nodeVersion);

        }

        $headers = $this->getUsageSignatureHeaders($usage, $userId);

        $curl    = $this->base->handleCurlRequest($url, [

            CURLOPT_FAILONERROR    => false,

            CURLOPT_POST           => 1,

            CURLOPT_POSTFIELDS     => json_encode($renderingParams),

            CURLOPT_RETURNTRANSFER => 1,

            CURLOPT_HTTPHEADER     => $headers

        ]);

        $data    = json_decode($curl->content, true, 512, JSON_THROW_ON_ERROR);

        $this->handleURLMapping($data, $usage);

        if ($curl->error === 0 && (int)($curl->info['http_code'] ?? 0) === 200) {

            return $data;

        }

        if ((int)($curl->info['http_code'] ?? 0) === 403) {

            throw new UsageDeletedException('the given usage is deleted and the requested node is not public');

        } else if ((int)($curl->info['http_code'] ?? 0) === 404) {

            throw new NodeDeletedException('the given node is already deleted ' . $curl->info['http_code'] . ': ' . $data['error'] . ' ' . $data['message']);

        } else {

            throw new Exception('fetching node by usage failed ' . $curl->info['http_code'] . ': ' . $data['error'] . ' ' . $data['message']);

        }

    }

    /**

     * Function deleteUsage

     *

     * Deletes the given usage

     * We trust that you've validated if the current user in your context is allowed to do so

     * There is no restriction in deleting usages even from foreign users, as long as they were generated by your app

     * Thus, this endpoint does not require any user ticket

     * @param string $nodeId

     * The edu-sharing node id this usage belongs to

     * @param string $usageId

     * The usage id

     * @throws UsageDeletedException

     * @throws Exception

     */

    public function deleteUsage(string $nodeId, string $usageId): void {

        $headers = $this->getSignatureHeaders($nodeId . $usageId);

        $curl    = $this->base->handleCurlRequest($this->base->baseUrl . '/rest/usage/v1/usages/node/' . rawurlencode($nodeId) . '/' . rawurlencode($usageId), [

            CURLOPT_FAILONERROR    => false,

            CURLOPT_CUSTOMREQUEST  => 'DELETE',

            CURLOPT_RETURNTRANSFER => 1,

            CURLOPT_HTTPHEADER     => $headers

        ]);

        if ($curl->error === 0 && (int)($curl->info['http_code'] ?? 0) === 200) {

            return;

        }

        if ((int)($curl->info['http_code'] ?? 0) === 404) {

            throw new UsageDeletedException('the given usage is already deleted or does not exist');

        } else {

            throw new Exception('deleting usage failed with curl error ' . $curl->error);

        }

    }

    /**

     * Function handleURLMapping

     *

     * @param $data

     * @param Usage $usage

     */

    private function handleURLMapping(&$data, Usage $usage): void {

        if (!$this->config->urlHandling->enabled) {

            return;

        }

        if (isset($data['node'])) {

            $params = '&usageId=' . urlencode($usage->usageId) . '&nodeId=' . urlencode($usage->nodeId) . '&resourceId=' . urlencode($usage->resourceId) . '&containerId=' . urlencode($usage->containerId);

            if ($usage->nodeVersion) {

                $params .= '&nodeVersion=' . urlencode($usage->nodeVersion);

            }

            $endpointBase           = $this->config->urlHandling->endpointURL . (str_contains($this->config->urlHandling->endpointURL, '?') ? '&' : '?');

            $contentUrl             = $endpointBase . 'mode=content' . $params;

            $data['url']            = [

                'content'  => $contentUrl,

                'download' => $endpointBase . 'mode=download' . $params

            ];

            $data['detailsSnippet'] = str_replace('{{{LMS_INLINE_HELPER_SCRIPT}}}', $contentUrl, $data['detailsSnippet']);

            $data['detailsSnippet'] = str_replace('{{{TICKET}}}', '', $data['detailsSnippet']);

        }

    }

    /**

     * Function getRedirectUrl

     *

     * @param string $mode

     * @param Usage $usage

     * @param array $additionalParams

     * Additional query params that shall be passed to the repository url (as key=>value structure)

     * @param string|null $userId

     * The user id. Note: Due to the current behaviour, this userId will currently NOT obeyed for the tracking results

     * of this method, the statistics/tracking when going into the full view will always be anonymous

     * @return string

     * @throws JsonException

     * @throws NodeDeletedException

     * @throws UsageDeletedException

     * @throws Exception

     */

    public function getRedirectUrl(string $mode, Usage $usage, array $additionalParams = [], ?string $userId = null): string {

        $headers = $this->getUsageSignatureHeaders($usage);

        // DisplayMode::PRERENDER is used in order to differentiate for tracking and statistics

        $node    = $this->getNodeByUsage($usage, DisplayMode::PRERENDER, null, $userId);

        $params  = '';

        foreach ($headers as $header) {

            if (!str_starts_with($header, 'X-')) {

                continue;

            }

            $header = explode(': ', $header);

            $params .= '&' . $header[0] . '=' . urlencode($header[1]);

        }

        foreach($additionalParams as $key => $value) {

            foreach ($headers as $header) {

                if($header[0] === $key) {

                    continue(2);

                }

            }

            $params .= '&' . $key . '=' . urlencode($value);

        }

        if ($mode === 'content') {

            $url    = $node['node']['content']['url'] ?? '';

            $params .= '&closeOnBack=true';

        } else if ($mode === 'download') {

            $url = $node['node']['downloadUrl'] ?? '';

        } else {

            throw new Exception('Unknown parameter for mode: ' . $mode);

        }

        return $url . (str_contains($url, '?') ? '' : '?') . $params;

    }

    /**

     * Function getUsageSignatureHeaders

     *

     * @param Usage $usage

     * @param string|null $userId

     * @return array

     */

    private function getUsageSignatureHeaders(Usage $usage, ?string $userId = null): array {

        $headers   = $this->getSignatureHeaders($usage->usageId);

        $headers[] = 'X-Edu-Usage-Node-Id: ' . $usage->nodeId;

        $headers[] = 'X-Edu-Usage-Course-Id: ' . $usage->containerId;

        $headers[] = 'X-Edu-Usage-Resource-Id: ' . $usage->resourceId;

        if ($userId !== null) {

            $headers[] = 'X-Edu-User-Id: ' . $userId;

        }

        return $headers;

    }

    /**

     * Function getPreview

     *

     * @param Usage $usage

     * @return CurlResult

     */

    public function getPreview(Usage $usage): CurlResult {

        $url = $this->base->baseUrl . '/preview?nodeId=' . rawurlencode($usage->nodeId) . '&maxWidth=400&maxHeight=400&crop=true';

        if ($usage->nodeVersion) {

            $url .= '&version=' . rawurlencode($usage->nodeVersion);

        }

        $headers = $this->getUsageSignatureHeaders($usage);

        return $this->base->handleCurlRequest($url, [

            CURLOPT_FAILONERROR    => false,

            CURLOPT_RETURNTRANSFER => 1,

            CURLOPT_HTTPHEADER     => $headers

        ]);

    }

}