first commit

mod/lti/classes/local/ltiservice/resource_base.php

@@ -0,0 +1,389 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains an abstract definition of an LTI resource
+ *
+ * @package    mod_lti
+ * @copyright  2014 Vital Source Technologies http://vitalsource.com
+ * @author     Stephen Vickers
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+
+namespace mod_lti\local\ltiservice;
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->dirroot . '/mod/lti/locallib.php');
+
+
+/**
+ * The mod_lti\local\ltiservice\resource_base class.
+ *
+ * @package    mod_lti
+ * @since      Moodle 2.8
+ * @copyright  2014 Vital Source Technologies http://vitalsource.com
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+abstract class resource_base {
+
+    /**  HTTP Post method */
+    const HTTP_POST = 'POST';
+    /**  HTTP Get method */
+    const HTTP_GET = 'GET';
+    /**  HTTP Put method */
+    const HTTP_PUT = 'PUT';
+    /**  HTTP Delete method */
+    const HTTP_DELETE = 'DELETE';
+
+    /** @var service_base Service associated with this resource. */
+    private $service;
+    /** @var string Type for this resource. */
+    protected $type;
+    /** @var string ID for this resource. */
+    protected $id;
+    /** @var string Template for this resource. */
+    protected $template;
+    /** @var array Custom parameter substitution variables associated with this resource. */
+    protected $variables;
+    /** @var array Media types supported by this resource. */
+    protected $formats;
+    /** @var array HTTP actions supported by this resource. */
+    protected $methods;
+    /** @var array Template variables parsed from the resource template. */
+    protected $params;
+
+
+    /**
+     * Class constructor.
+     *
+     * @param service_base $service Service instance
+     */
+    public function __construct($service) {
+
+        $this->service = $service;
+        $this->type = 'RestService';
+        $this->id = null;
+        $this->template = null;
+        $this->methods = array();
+        $this->variables = array();
+        $this->formats = array();
+        $this->methods = array();
+        $this->params = null;
+
+    }
+
+    /**
+     * Get the resource ID.
+     *
+     * @return string
+     */
+    public function get_id() {
+
+        return $this->id;
+
+    }
+
+    /**
+     * Get the resource template.
+     *
+     * @return string
+     */
+    public function get_template() {
+
+        return $this->template;
+
+    }
+
+    /**
+     * Get the resource path.
+     *
+     * @return string
+     */
+    public function get_path() {
+
+        return $this->get_template();
+
+    }
+
+    /**
+     * Get the resource type.
+     *
+     * @return string
+     */
+    public function get_type() {
+
+        return $this->type;
+
+    }
+
+    /**
+     * Get the resource's service.
+     *
+     * @return service_base
+     */
+    public function get_service() {
+
+        return $this->service;
+
+    }
+
+    /**
+     * Get the resource methods.
+     *
+     * @return array
+     */
+    public function get_methods() {
+
+        return $this->methods;
+
+    }
+
+    /**
+     * Get the resource media types.
+     *
+     * @return array
+     */
+    public function get_formats() {
+
+        return $this->formats;
+
+    }
+
+    /**
+     * Get the resource template variables.
+     *
+     * @return array
+     */
+    public function get_variables() {
+
+        return $this->variables;
+
+    }
+
+    /**
+     * Get the resource fully qualified endpoint.
+     *
+     * @return string
+     */
+    public function get_endpoint() {
+
+        $this->parse_template();
+        $template = preg_replace('/[\(\)]/', '', $this->get_template());
+        $url = $this->get_service()->get_service_path() . $template;
+        foreach ($this->params as $key => $value) {
+            $url = str_replace('{' . $key . '}', $value, $url);
+        }
+        $toolproxy = $this->get_service()->get_tool_proxy();
+        if (!empty($toolproxy)) {
+            $url = str_replace('{config_type}', 'toolproxy', $url);
+            $url = str_replace('{tool_proxy_id}', $toolproxy->guid, $url);
+        } else {
+            $url = str_replace('{config_type}', 'tool', $url);
+            $url = str_replace('{tool_proxy_id}', $this->get_service()->get_type()->id, $url);
+        }
+
+        return $url;
+
+    }
+
+    /**
+     * Execute the request for this resource.
+     *
+     * @param response $response  Response object for this request.
+     */
+    abstract public function execute($response);
+
+    /**
+     * Check to make sure the request is valid.
+     *
+     * @param int $typeid                   The typeid we want to use
+     * @param string $body                  Body of HTTP request message
+     * @param string[] $scopes              Array of scope(s) required for incoming request
+     *
+     * @return boolean
+     */
+    public function check_tool($typeid, $body = null, $scopes = null) {
+
+        $ok = $this->get_service()->check_tool($typeid, $body, $scopes);
+        if ($ok) {
+            if ($this->get_service()->get_tool_proxy()) {
+                $toolproxyjson = $this->get_service()->get_tool_proxy()->toolproxy;
+            }
+            if (!empty($toolproxyjson)) {
+                // Check tool proxy to ensure service being requested is included.
+                $toolproxy = json_decode($toolproxyjson);
+                if (!empty($toolproxy) && isset($toolproxy->security_contract->tool_service)) {
+                    $contexts = lti_get_contexts($toolproxy);
+                    $tpservices = $toolproxy->security_contract->tool_service;
+                    foreach ($tpservices as $service) {
+                        $fqid = lti_get_fqid($contexts, $service->service);
+                        $id = explode('#', $fqid, 2);
+                        if ($this->get_id() === $id[1]) {
+                            $ok = true;
+                            break;
+                        }
+                    }
+                }
+                if (!$ok) {
+                    debugging('Requested service not permitted: ' . $this->get_id(), DEBUG_DEVELOPER);
+                }
+            } else {
+                // Check that the scope required for the service request is included in those granted for the
+                // access token being used.
+                $permittedscopes = $this->get_service()->get_permitted_scopes();
+                $ok = is_null($permittedscopes) || empty($scopes) || !empty(array_intersect($permittedscopes, $scopes));
+            }
+        }
+
+        return $ok;
+
+    }
+
+    /**
+     * Check to make sure the request is valid.
+     *
+     * @param string $toolproxyguid Consumer key
+     * @param string $body          Body of HTTP request message
+     *
+     * @return boolean
+     * @deprecated since Moodle 3.7 MDL-62599 - please do not use this function any more.
+     * @see resource_base::check_tool()
+     */
+    public function check_tool_proxy($toolproxyguid, $body = null) {
+
+        debugging('check_tool_proxy() is deprecated to allow LTI 1 connections to support services. ' .
+                  'Please use resource_base::check_tool() instead.', DEBUG_DEVELOPER);
+        $ok = false;
+        if ($this->get_service()->check_tool_proxy($toolproxyguid, $body)) {
+            $toolproxyjson = $this->get_service()->get_tool_proxy()->toolproxy;
+            if (empty($toolproxyjson)) {
+                $ok = true;
+            } else {
+                $toolproxy = json_decode($toolproxyjson);
+                if (!empty($toolproxy) && isset($toolproxy->security_contract->tool_service)) {
+                    $contexts = lti_get_contexts($toolproxy);
+                    $tpservices = $toolproxy->security_contract->tool_service;
+                    foreach ($tpservices as $service) {
+                        $fqid = lti_get_fqid($contexts, $service->service);
+                        $id = explode('#', $fqid, 2);
+                        if ($this->get_id() === $id[1]) {
+                            $ok = true;
+                            break;
+                        }
+                    }
+                }
+                if (!$ok) {
+                    debugging('Requested service not included in tool proxy: ' . $this->get_id());
+                }
+            }
+        }
+
+        return $ok;
+
+    }
+
+    /**
+     * Check to make sure the request is valid.
+     *
+     * @param int $typeid                   The typeid we want to use
+     * @param int $contextid                The course we are at
+     * @param string $permissionrequested   The permission to be checked
+     * @param string $body                  Body of HTTP request message
+     *
+     * @return boolean
+     * @deprecated since Moodle 3.7 MDL-62599 - please do not use this function any more.
+     * @see resource_base::check_tool()
+     */
+    public function check_type($typeid, $contextid, $permissionrequested, $body = null) {
+        debugging('check_type() is deprecated to allow LTI 1 connections to support services. ' .
+                  'Please use resource_base::check_tool() instead.', DEBUG_DEVELOPER);
+        $ok = false;
+        if ($this->get_service()->check_type($typeid, $contextid, $body)) {
+            $neededpermissions = $this->get_permissions($typeid);
+            foreach ($neededpermissions as $permission) {
+                if ($permission == $permissionrequested) {
+                    $ok = true;
+                    break;
+                }
+            }
+            if (!$ok) {
+                debugging('Requested service ' . $permissionrequested . ' not included in tool type: ' . $typeid,
+                    DEBUG_DEVELOPER);
+            }
+        }
+        return $ok;
+    }
+
+    /**
+     * get permissions from the config of the tool for that resource
+     *
+     * @param int $ltitype Type of LTI
+     * @return array with the permissions related to this resource by the $ltitype or empty if none.
+     * @deprecated since Moodle 3.7 MDL-62599 - please do not use this function any more.
+     * @see resource_base::check_tool()
+     */
+    public function get_permissions($ltitype) {
+        debugging('get_permissions() is deprecated to allow LTI 1 connections to support services. ' .
+                  'Please use resource_base::check_tool() instead.', DEBUG_DEVELOPER);
+        return array();
+    }
+
+    /**
+     * Parse a value for custom parameter substitution variables.
+     *
+     * @param string $value String to be parsed
+     *
+     * @return string
+     */
+    public function parse_value($value) {
+
+        return $value;
+
+    }
+
+    /**
+     * Parse the template for variables.
+     *
+     * @return array
+     */
+    protected function parse_template() {
+
+        if (empty($this->params)) {
+            $this->params = array();
+            if (!empty($_SERVER['PATH_INFO'])) {
+                $path = explode('/', $_SERVER['PATH_INFO']);
+                $template = preg_replace('/\([0-9a-zA-Z_\-,\/]+\)/', '', $this->get_template());
+                $parts = explode('/', $template);
+                for ($i = 0; $i < count($parts); $i++) {
+                    if ((substr($parts[$i], 0, 1) == '{') && (substr($parts[$i], -1) == '}')) {
+                        $value = '';
+                        if ($i < count($path)) {
+                            $value = $path[$i];
+                        }
+                        $this->params[substr($parts[$i], 1, -1)] = $value;
+                    }
+                }
+            }
+        }
+
+        return $this->params;
+
+    }
+
+}

mod/lti/classes/local/ltiservice/response.php

@@ -0,0 +1,263 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains an abstract definition of an LTI service
+ *
+ * @package    mod_lti
+ * @copyright  2014 Vital Source Technologies http://vitalsource.com
+ * @author     Stephen Vickers
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+
+namespace mod_lti\local\ltiservice;
+
+defined('MOODLE_INTERNAL') || die;
+
+/**
+ * The mod_lti\local\ltiservice\response class.
+ *
+ * @package    mod_lti
+ * @since      Moodle 2.8
+ * @copyright  2014 Vital Source Technologies http://vitalsource.com
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class response {
+
+    /** @var int HTTP response code. */
+    private $code;
+    /** @var string HTTP response reason. */
+    private $reason;
+    /** @var string HTTP request method. */
+    private $requestmethod;
+    /** @var string HTTP request accept header. */
+    private $accept;
+    /** @var string HTTP response content type. */
+    private $contenttype;
+    /** @var string HTTP request body. */
+    private $data;
+    /** @var string HTTP response body. */
+    private $body;
+    /** @var array HTTP response codes. */
+    private $responsecodes;
+    /** @var array HTTP additional headers. */
+    private $additionalheaders;
+
+    /**
+     * Class constructor.
+     */
+    public function __construct() {
+
+        $this->code = 200;
+        $this->reason = '';
+        $this->requestmethod = $_SERVER['REQUEST_METHOD'];
+        $this->accept = '';
+        $this->contenttype = '';
+        $this->data = '';
+        $this->body = '';
+        $this->responsecodes = array(
+            200 => 'OK',
+            201 => 'Created',
+            202 => 'Accepted',
+            300 => 'Multiple Choices',
+            400 => 'Bad Request',
+            401 => 'Unauthorized',
+            402 => 'Payment Required',
+            403 => 'Forbidden',
+            404 => 'Not Found',
+            405 => 'Method Not Allowed',
+            406 => 'Not Acceptable',
+            415 => 'Unsupported Media Type',
+            500 => 'Internal Server Error',
+            501 => 'Not Implemented'
+        );
+        $this->additionalheaders = array();
+
+    }
+
+    /**
+     * Get the response code.
+     *
+     * @return int
+     */
+    public function get_code() {
+        return $this->code;
+    }
+
+    /**
+     * Set the response code.
+     *
+     * @param int $code Response code
+     */
+    public function set_code($code) {
+        $this->code = $code;
+        $this->reason = '';
+    }
+
+    /**
+     * Get the response reason.
+     *
+     * @return string
+     */
+    public function get_reason() {
+        $code = $this->code;
+        if (($code < 200) || ($code >= 600)) {
+            $code = 500;  // Status code must be between 200 and 599.
+        }
+        if (empty($this->reason) && array_key_exists($code, $this->responsecodes)) {
+            $this->reason = $this->responsecodes[$code];
+        }
+        // Use generic reason for this category (based on first digit) if a specific reason is not defined.
+        if (empty($this->reason)) {
+            $this->reason = $this->responsecodes[intval($code / 100) * 100];
+        }
+        return $this->reason;
+    }
+
+    /**
+     * Set the response reason.
+     *
+     * @param string $reason Reason
+     */
+    public function set_reason($reason) {
+        $this->reason = $reason;
+    }
+
+    /**
+     * Get the request method.
+     *
+     * @return string
+     */
+    public function get_request_method() {
+        return $this->requestmethod;
+    }
+
+    /**
+     * Get the request accept header.
+     *
+     * @return string
+     */
+    public function get_accept() {
+        return $this->accept;
+    }
+
+    /**
+     * Set the request accept header.
+     *
+     * @param string $accept Accept header value
+     */
+    public function set_accept($accept) {
+        $this->accept = $accept;
+    }
+
+    /**
+     * Get the response content type.
+     *
+     * @return string
+     */
+    public function get_content_type() {
+        return $this->contenttype;
+    }
+
+    /**
+     * Set the response content type.
+     *
+     * @param string $contenttype Content type
+     */
+    public function set_content_type($contenttype) {
+        $this->contenttype = $contenttype;
+    }
+
+    /**
+     * Get the request body.
+     *
+     * @return string
+     */
+    public function get_request_data() {
+        return $this->data;
+    }
+
+    /**
+     * Set the response body.
+     *
+     * @param string $data Body data
+     */
+    public function set_request_data($data) {
+        $this->data = $data;
+    }
+
+    /**
+     * Get the response body.
+     *
+     * @return string
+     */
+    public function get_body() {
+        return $this->body;
+    }
+
+    /**
+     * Set the response body.
+     *
+     * @param string $body Body data
+     */
+    public function set_body($body) {
+        $this->body = $body;
+    }
+
+    /**
+     * Add an additional header.
+     *
+     * @param string $header The new header
+     */
+    public function add_additional_header($header) {
+        array_push($this->additionalheaders, $header);
+    }
+
+    /**
+     * Send the response.
+     */
+    public function send() {
+        header("HTTP/1.0 {$this->code} {$this->get_reason()}");
+        foreach ($this->additionalheaders as $header) {
+            header($header);
+        }
+        if ((($this->code >= 200) && ($this->code < 300)) || !empty($this->body)) {
+            if (!empty($this->contenttype)) {
+                header("Content-Type: {$this->contenttype}; charset=utf-8");
+            }
+            if (!empty($this->body)) {
+                echo $this->body;
+            }
+        } else if ($this->code >= 400) {
+            header("Content-Type: application/json; charset=utf-8");
+            $body = new \stdClass();
+            $body->status = $this->code;
+            $body->reason = $this->get_reason();
+            $body->request = new \stdClass();
+            $body->request->method = $_SERVER['REQUEST_METHOD'];
+            $body->request->url = $_SERVER['REQUEST_URI'];
+            if (isset($_SERVER['HTTP_ACCEPT'])) {
+                $body->request->accept = $_SERVER['HTTP_ACCEPT'];
+            }
+            if (isset($_SERVER['CONTENT_TYPE'])) {
+                $body->request->contentType = explode(';', $_SERVER['CONTENT_TYPE'], 2)[0];
+            }
+            echo json_encode($body, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES);
+        }
+    }
+
+}

mod/lti/classes/local/ltiservice/service_base.php

@@ -0,0 +1,548 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains an abstract definition of an LTI service
+ *
+ * @package    mod_lti
+ * @copyright  2014 Vital Source Technologies http://vitalsource.com
+ * @author     Stephen Vickers
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+
+namespace mod_lti\local\ltiservice;
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->dirroot . '/mod/lti/locallib.php');
+require_once($CFG->dirroot . '/mod/lti/OAuthBody.php');
+
+// TODO: Switch to core oauthlib once implemented - MDL-30149.
+use moodle\mod\lti as lti;
+use stdClass;
+
+
+/**
+ * The mod_lti\local\ltiservice\service_base class.
+ *
+ * @package    mod_lti
+ * @since      Moodle 2.8
+ * @copyright  2014 Vital Source Technologies http://vitalsource.com
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+abstract class service_base {
+
+    /** Label representing an LTI 2 message type */
+    const LTI_VERSION2P0 = 'LTI-2p0';
+    /** Service enabled */
+    const SERVICE_ENABLED = 1;
+
+    /** @var string ID for the service. */
+    protected $id;
+    /** @var string Human readable name for the service. */
+    protected $name;
+    /** @var boolean <code>true</code> if requests for this service do not need to be signed. */
+    protected $unsigned;
+    /** @var stdClass Tool proxy object for the current service request. */
+    private $toolproxy;
+    /** @var stdClass LTI type object for the current service request. */
+    private $type;
+    /** @var array LTI type config array for the current service request. */
+    private $typeconfig;
+    /** @var array Instances of the resources associated with this service. */
+    protected $resources;
+
+
+    /**
+     * Class constructor.
+     */
+    public function __construct() {
+
+        $this->id = null;
+        $this->name = null;
+        $this->unsigned = false;
+        $this->toolproxy = null;
+        $this->type = null;
+        $this->typeconfig = null;
+        $this->resources = null;
+
+    }
+
+    /**
+     * Get the service ID.
+     *
+     * @return string
+     */
+    public function get_id() {
+
+        return $this->id;
+
+    }
+
+    /**
+     * Get the service compoent ID.
+     *
+     * @return string
+     */
+    public function get_component_id() {
+
+        return 'ltiservice_' . $this->id;
+
+    }
+
+    /**
+     * Get the service name.
+     *
+     * @return string
+     */
+    public function get_name() {
+
+        return $this->name;
+
+    }
+
+    /**
+     * Get whether the service requests need to be signed.
+     *
+     * @return boolean
+     */
+    public function is_unsigned() {
+
+        return $this->unsigned;
+
+    }
+
+    /**
+     * Get the tool proxy object.
+     *
+     * @return stdClass
+     */
+    public function get_tool_proxy() {
+
+        return $this->toolproxy;
+
+    }
+
+    /**
+     * Set the tool proxy object.
+     *
+     * @param object $toolproxy The tool proxy for this service request
+     *
+     * @var stdClass
+     */
+    public function set_tool_proxy($toolproxy) {
+
+        $this->toolproxy = $toolproxy;
+
+    }
+
+    /**
+     * Get the type object.
+     *
+     * @return stdClass
+     */
+    public function get_type() {
+
+        return $this->type;
+
+    }
+
+    /**
+     * Set the LTI type object.
+     *
+     * @param object $type The LTI type for this service request
+     *
+     * @var stdClass
+     */
+    public function set_type($type) {
+
+        $this->type = $type;
+
+    }
+
+    /**
+     * Get the type config array.
+     *
+     * @return array|null
+     */
+    public function get_typeconfig() {
+
+        return $this->typeconfig;
+
+    }
+
+    /**
+     * Set the LTI type config object.
+     *
+     * @param array $typeconfig The LTI type config for this service request
+     *
+     * @var array
+     */
+    public function set_typeconfig($typeconfig) {
+
+        $this->typeconfig = $typeconfig;
+
+    }
+
+    /**
+     * Get the resources for this service.
+     *
+     * @return resource_base[]
+     */
+    abstract public function get_resources();
+
+    /**
+     * Get the scope(s) permitted for this service in the context of a particular tool type.
+     *
+     * A null value indicates that no scopes are required to access the service.
+     *
+     * @return array|null
+     */
+    public function get_permitted_scopes() {
+        return null;
+    }
+
+    /**
+     * Get the scope(s) permitted for this service.
+     *
+     * A null value indicates that no scopes are required to access the service.
+     *
+     * @return array|null
+     */
+    public function get_scopes() {
+        return null;
+    }
+
+    /**
+     * Returns the configuration options for this service.
+     *
+     * @param \MoodleQuickForm $mform Moodle quickform object definition
+     */
+    public function get_configuration_options(&$mform) {
+
+    }
+
+    /**
+     * Called when a new LTI Instance is added.
+     *
+     * @param object $lti LTI Instance.
+     */
+    public function instance_added(object $lti): void {
+
+    }
+
+    /**
+     * Called when a new LTI Instance is updated.
+     *
+     * @param object $lti LTI Instance.
+     */
+    public function instance_updated(object $lti): void {
+
+    }
+
+    /**
+     * Called when the launch data is created, offering a possibility to alter the
+     * target link URI.
+     *
+     * @param string $messagetype message type for this launch
+     * @param string $targetlinkuri current target link uri
+     * @param null|string $customstr concatenated list of custom parameters
+     * @param int $courseid
+     * @param null|object $lti LTI Instance.
+     *
+     * @return array containing the target link URL and the custom params string to use.
+     */
+    public function override_endpoint(string $messagetype, string $targetlinkuri,
+            ?string $customstr, int $courseid, ?object $lti = null): array {
+        return [$targetlinkuri, $customstr];
+    }
+
+    /**
+     * Called when a new LTI Instance is deleted.
+     *
+     * @param int $id LTI Instance.
+     */
+    public function instance_deleted(int $id): void {
+
+    }
+
+    /**
+     * Set the form data when displaying the LTI Instance form.
+     *
+     * @param object $defaultvalues Default form values.
+     */
+    public function set_instance_form_values(object $defaultvalues): void {
+
+    }
+
+    /**
+     * Return an array with the names of the parameters that the service will be saving in the configuration
+     *
+     * @return array  Names list of the parameters that the service will be saving in the configuration
+     * @deprecated since Moodle 3.7 - please do not use this function any more.
+     */
+    public function get_configuration_parameter_names() {
+        debugging('get_configuration_parameter_names() has been deprecated.', DEBUG_DEVELOPER);
+        return array();
+    }
+
+    /**
+     * Default implementation will check for the existence of at least one mod_lti entry for that tool and context.
+     *
+     * It may be overridden if other inferences can be done.
+     *
+     * Ideally a Site Tool should be explicitly engaged with a course, the check on the presence of a link is a proxy
+     * to infer a Site Tool engagement until an explicit Site Tool - Course relationship exists.
+     *
+     * @param int $typeid The tool lti type id.
+     * @param int $courseid The course id.
+     * @return bool returns True if tool is used in context, false otherwise.
+     */
+    public function is_used_in_context($typeid, $courseid) {
+        global $DB;
+
+        $ok = $DB->record_exists('lti', array('course' => $courseid, 'typeid' => $typeid));
+        return $ok || $DB->record_exists('lti_types', array('course' => $courseid, 'id' => $typeid));
+    }
+
+    /**
+     * Checks if there is a site tool or a course tool for this site.
+     *
+     * @param int $typeid The tool lti type id.
+     * @param int $courseid The course id.
+     * @return bool returns True if tool is allowed in context, false otherwise.
+     */
+    public function is_allowed_in_context($typeid, $courseid) {
+        global $DB;
+
+        // Check if it is a Course tool for this course or a Site tool.
+        $type = $DB->get_record('lti_types', array('id' => $typeid));
+
+        return $type && ($type->course == $courseid || $type->course == SITEID);
+    }
+
+    /**
+     * Return an array of key/values to add to the launch parameters.
+     *
+     * @param string $messagetype  'basic-lti-launch-request' or 'ContentItemSelectionRequest'.
+     * @param string $courseid     The course id.
+     * @param string $userid       The user id.
+     * @param string $typeid       The tool lti type id.
+     * @param string $modlti       The id of the lti activity.
+     *
+     * The type is passed to check the configuration and not return parameters for services not used.
+     *
+     * @return array Key/value pairs to add as launch parameters.
+     */
+    public function get_launch_parameters($messagetype, $courseid, $userid, $typeid, $modlti = null) {
+        return array();
+    }
+
+    /**
+     * Return an array of key/claim mapping allowing LTI 1.1 custom parameters
+     * to be transformed to LTI 1.3 claims.
+     *
+     * @return array Key/value pairs of params to claim mapping.
+     */
+    public function get_jwt_claim_mappings(): array {
+        return [];
+    }
+
+    /**
+     * Get the path for service requests.
+     *
+     * @return string
+     */
+    public static function get_service_path() {
+
+        $url = new \moodle_url('/mod/lti/services.php');
+
+        return $url->out(false);
+
+    }
+
+    /**
+     * Parse a string for custom substitution parameter variables supported by this service's resources.
+     *
+     * @param string $value  Value to be parsed
+     *
+     * @return string
+     */
+    public function parse_value($value) {
+
+        if (empty($this->resources)) {
+            $this->resources = $this->get_resources();
+        }
+        if (!empty($this->resources)) {
+            foreach ($this->resources as $resource) {
+                $value = $resource->parse_value($value);
+            }
+        }
+
+        return $value;
+
+    }
+
+    /**
+     * Check that the request has been properly signed and is permitted.
+     *
+     * @param string $typeid    LTI type ID
+     * @param string $body      Request body (null if none)
+     * @param string[] $scopes  Array of required scope(s) for incoming request
+     *
+     * @return boolean
+     */
+    public function check_tool($typeid, $body = null, $scopes = null) {
+
+        $ok = true;
+        $toolproxy = null;
+        $consumerkey = lti\get_oauth_key_from_headers($typeid, $scopes);
+        if ($consumerkey === false) {
+            $ok = $this->is_unsigned();
+        } else {
+            if (empty($typeid) && is_int($consumerkey)) {
+                $typeid = $consumerkey;
+            }
+            if (!empty($typeid)) {
+                $this->type = lti_get_type($typeid);
+                $this->typeconfig = lti_get_type_config($typeid);
+                $ok = !empty($this->type->id);
+                if ($ok && !empty($this->type->toolproxyid)) {
+                    $this->toolproxy = lti_get_tool_proxy($this->type->toolproxyid);
+                }
+            } else {
+                $toolproxy = lti_get_tool_proxy_from_guid($consumerkey);
+                if ($toolproxy !== false) {
+                    $this->toolproxy = $toolproxy;
+                }
+            }
+        }
+        if ($ok && is_string($consumerkey)) {
+            if (!empty($this->toolproxy)) {
+                $key = $this->toolproxy->guid;
+                $secret = $this->toolproxy->secret;
+            } else {
+                $key = $this->typeconfig['resourcekey'];
+                $secret = $this->typeconfig['password'];
+            }
+            if (!$this->is_unsigned() && ($key == $consumerkey)) {
+                $ok = $this->check_signature($key, $secret, $body);
+            } else {
+                $ok = $this->is_unsigned();
+            }
+        }
+
+        return $ok;
+
+    }
+
+    /**
+     * Check that the request has been properly signed.
+     *
+     * @param string $toolproxyguid  Tool Proxy GUID
+     * @param string $body           Request body (null if none)
+     *
+     * @return boolean
+     * @deprecated since Moodle 3.7 MDL-62599 - please do not use this function any more.
+     * @see service_base::check_tool()
+     */
+    public function check_tool_proxy($toolproxyguid, $body = null) {
+
+        debugging('check_tool_proxy() is deprecated to allow LTI 1 connections to support services. ' .
+                  'Please use service_base::check_tool() instead.', DEBUG_DEVELOPER);
+        $ok = false;
+        $toolproxy = null;
+        $consumerkey = lti\get_oauth_key_from_headers();
+        if (empty($toolproxyguid)) {
+            $toolproxyguid = $consumerkey;
+        }
+
+        if (!empty($toolproxyguid)) {
+            $toolproxy = lti_get_tool_proxy_from_guid($toolproxyguid);
+            if ($toolproxy !== false) {
+                if (!$this->is_unsigned() && ($toolproxy->guid == $consumerkey)) {
+                    $ok = $this->check_signature($toolproxy->guid, $toolproxy->secret, $body);
+                } else {
+                    $ok = $this->is_unsigned();
+                }
+            }
+        }
+        if ($ok) {
+            $this->toolproxy = $toolproxy;
+        }
+
+        return $ok;
+
+    }
+
+    /**
+     * Check that the request has been properly signed.
+     *
+     * @param int $typeid The tool id
+     * @param int $courseid The course we are at
+     * @param string $body Request body (null if none)
+     *
+     * @return bool
+     * @deprecated since Moodle 3.7 MDL-62599 - please do not use this function any more.
+     * @see service_base::check_tool()
+     */
+    public function check_type($typeid, $courseid, $body = null) {
+        debugging('check_type() is deprecated to allow LTI 1 connections to support services. ' .
+                  'Please use service_base::check_tool() instead.', DEBUG_DEVELOPER);
+        $ok = false;
+        $tool = null;
+        $consumerkey = lti\get_oauth_key_from_headers();
+        if (empty($typeid)) {
+            return $ok;
+        } else if ($this->is_allowed_in_context($typeid, $courseid)) {
+            $tool = lti_get_type_type_config($typeid);
+            if ($tool !== false) {
+                if (!$this->is_unsigned() && ($tool->lti_resourcekey == $consumerkey)) {
+                    $ok = $this->check_signature($tool->lti_resourcekey, $tool->lti_password, $body);
+                } else {
+                    $ok = $this->is_unsigned();
+                }
+            }
+        }
+        return $ok;
+    }
+
+    /**
+     * Check the request signature.
+     *
+     * @param string $consumerkey    Consumer key
+     * @param string $secret         Shared secret
+     * @param string $body           Request body
+     *
+     * @return boolean
+     */
+    private function check_signature($consumerkey, $secret, $body) {
+
+        $ok = true;
+        try {
+            // TODO: Switch to core oauthlib once implemented - MDL-30149.
+            lti\handle_oauth_body_post($consumerkey, $secret, $body);
+        } catch (\Exception $e) {
+            debugging($e->getMessage() . "\n");
+            $ok = false;
+        }
+
+        return $ok;
+
+    }
+}