first commit

lib/classes/oauth2/service/clever.php

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+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\issuer;
+use core\oauth2\discovery\openidconnect;
+use core\oauth2\user_field_mapping;
+
+/**
+ * Class for Clever OAuth service, with the specific methods related to it.
+ *
+ * @package    core
+ * @copyright  2022 OpenStax
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class clever extends openidconnect implements issuer_interface {
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer The issuer initialised with proper default values.
+     */
+    public static function init(): issuer {
+        $record = (object) [
+            'name' => 'Clever',
+            'image' => 'https://apps.clever.com/favicon.ico',
+            'basicauth' => 1,
+            'baseurl' => 'https://clever.com',
+            'showonloginpage' => issuer::LOGINONLY,
+            'servicetype' => 'clever',
+        ];
+
+        return new issuer(0, $record);
+    }
+
+    /**
+     * Create field mappings for this issuer.
+     *
+     * @param issuer $issuer Issuer the field mappings should be created for.
+     */
+    public static function create_field_mappings(issuer $issuer): void {
+        // Perform OIDC default field mapping.
+        parent::create_field_mappings($issuer);
+
+        // Create the additional 'sub' field mapping.
+        $record = (object) [
+            'issuerid' => $issuer->get('id'),
+            'externalfield' => 'sub',
+            'internalfield' => 'idnumber',
+        ];
+        $userfieldmapping = new user_field_mapping(0, $record);
+        $userfieldmapping->create();
+    }
+}

lib/classes/oauth2/service/custom.php

@@ -0,0 +1,41 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\issuer;
+use core\oauth2\discovery\openidconnect;
+
+/**
+ * Class for Custom services, with the specific methods related to it.
+ *
+ * @package    core
+ * @copyright  2021 Sara Arjona (sara@moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class custom extends openidconnect implements issuer_interface {
+
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer|null The issuer initialised with proper default values.
+     */
+    public static function init(): ?issuer {
+        // Custom service doesn't require any particular initialization.
+        return null;
+    }
+
+}

lib/classes/oauth2/service/facebook.php

@@ -0,0 +1,109 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\issuer;
+use core\oauth2\endpoint;
+use core\oauth2\user_field_mapping;
+use core\oauth2\discovery\openidconnect;
+
+/**
+ * Class for Facebook oAuth service, with the specific methods related to it.
+ *
+ * @package    core
+ * @copyright  2021 Sara Arjona (sara@moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class facebook extends openidconnect implements issuer_interface {
+
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer The issuer initialised with proper default values.
+     */
+    public static function init(): issuer {
+        $record = (object) [
+            'name' => 'Facebook',
+            'image' => 'https://facebookbrand.com/wp-content/uploads/2016/05/flogo_rgb_hex-brc-site-250.png',
+            'baseurl' => '',
+            'loginscopes' => 'public_profile email',
+            'loginscopesoffline' => 'public_profile email',
+            'showonloginpage' => issuer::EVERYWHERE,
+            'servicetype' => 'facebook',
+        ];
+
+        $issuer = new issuer(0, $record);
+        return $issuer;
+    }
+
+    /**
+     * Create endpoints for this issuer.
+     *
+     * @param issuer $issuer Issuer the endpoints should be created for.
+     * @return issuer
+     */
+    public static function create_endpoints(issuer $issuer): issuer {
+        // The Facebook API version.
+        $apiversion = '2.12';
+        // The Graph API URL.
+        $graphurl = 'https://graph.facebook.com/v' . $apiversion;
+        // User information fields that we want to fetch.
+        $infofields = [
+            'id',
+            'first_name',
+            'last_name',
+            'picture.type(large)',
+            'name',
+            'email',
+        ];
+        $endpoints = [
+            'authorization_endpoint' => sprintf('https://www.facebook.com/v%s/dialog/oauth', $apiversion),
+            'token_endpoint' => $graphurl . '/oauth/access_token',
+            'userinfo_endpoint' => $graphurl . '/me?fields=' . implode(',', $infofields)
+        ];
+
+        foreach ($endpoints as $name => $url) {
+            $record = (object) [
+                'issuerid' => $issuer->get('id'),
+                'name' => $name,
+                'url' => $url
+            ];
+            $endpoint = new endpoint(0, $record);
+            $endpoint->create();
+        }
+
+        // Create the field mappings.
+        $mapping = [
+            'name' => 'alternatename',
+            'last_name' => 'lastname',
+            'email' => 'email',
+            'first_name' => 'firstname',
+            'picture-data-url' => 'picture',
+        ];
+        foreach ($mapping as $external => $internal) {
+            $record = (object) [
+                'issuerid' => $issuer->get('id'),
+                'externalfield' => $external,
+                'internalfield' => $internal
+            ];
+            $userfieldmapping = new user_field_mapping(0, $record);
+            $userfieldmapping->create();
+        }
+
+        return $issuer;
+    }
+}

lib/classes/oauth2/service/google.php

@@ -0,0 +1,50 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\issuer;
+use core\oauth2\discovery\openidconnect;
+
+/**
+ * Class for Google oAuth service, with the specific methods related to it.
+ *
+ * @package    core
+ * @copyright  2021 Sara Arjona (sara@moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class google extends openidconnect implements issuer_interface {
+
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer|null The issuer initialised with proper default values.
+     */
+    public static function init(): ?issuer {
+        $record = (object) [
+            'name' => 'Google',
+            'image' => 'https://accounts.google.com/favicon.ico',
+            'baseurl' => 'https://accounts.google.com/',
+            'loginparamsoffline' => 'access_type=offline&prompt=consent',
+            'showonloginpage' => issuer::EVERYWHERE,
+            'servicetype' => 'google',
+        ];
+        $issuer = new issuer(0, $record);
+
+        return $issuer;
+    }
+
+}

lib/classes/oauth2/service/imsobv2p1.php

@@ -0,0 +1,57 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\issuer;
+use core\oauth2\discovery\imsbadgeconnect;
+
+/**
+ * Class for IMS Open Badges v2.1 oAuth service, with the specific methods related to it.
+ *
+ * @package    core
+ * @copyright  2021 Sara Arjona (sara@moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class imsobv2p1 extends imsbadgeconnect implements issuer_interface {
+
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer|null The issuer initialised with proper default values.
+     */
+    public static function init(): ?issuer {
+        $record = (object) [
+            'name' => 'Open Badges',
+            'image' => '',
+            'servicetype' => 'imsobv2p1',
+        ];
+
+        $issuer = new issuer(0, $record);
+        return $issuer;
+    }
+
+    /**
+     * Process how to map user field information.
+     *
+     * @param issuer $issuer The OAuth issuer the endpoints should be discovered for.
+     * @return void
+     */
+    public static function create_field_mappings(issuer $issuer): void {
+        // There are no specific field mappings for this service.
+    }
+
+}

lib/classes/oauth2/service/issuer_interface.php

@@ -0,0 +1,53 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\issuer;
+
+/**
+ * Interface for services, with the methods to be implemented by all the issuer implementing it.
+ *
+ * @package    core
+ * @copyright  2021 Sara Arjona (sara@moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+interface issuer_interface {
+
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer|null The issuer initialised with proper default values, or null if no issuer is initialised.
+     */
+    public static function init(): ?issuer;
+
+    /**
+     * Create endpoints for this issuer.
+     *
+     * @param issuer $issuer Issuer the endpoints should be created for.
+     * @return issuer
+     */
+    public static function create_endpoints(issuer $issuer): issuer;
+
+    /**
+     * If the discovery endpoint exists for this issuer, try and determine the list of valid endpoints.
+     *
+     * @param issuer $issuer
+     * @return int The number of discovered services.
+     */
+    public static function discover_endpoints($issuer): int;
+
+}

lib/classes/oauth2/service/linkedin.php

@@ -0,0 +1,60 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\discovery\openidconnect;
+use core\oauth2\issuer;
+
+/**
+ * Class linkedin.
+ *
+ * OAuth 2 issuer for linkedin which is mostly OIDC compliant, with a few notable exceptions which require working around:
+ *
+ * 1. LinkedIn don't provide their OIDC discovery doc at {ISSUER}/.well-known/openid-configuration as the spec requires.
+ * i.e. https://www.linkedin.com/.well-known/openid-configuration isn't present.
+ * Instead, they make the configuration available at https://www.linkedin.com/oauth/.well-known/openid-configuration.
+ * See: https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfig
+ *
+ * 2. LinkedIn don't return 'locale' as a string in the userinfo but instead return an object with 'language' and 'country' props.
+ * See: https://openid.net/specs/openid-connect-core-1_0.html#StandardClaims
+ * This is resolved in {@see \core\oauth2\client\linkedin::get_userinfo()}
+ *
+ * @copyright  2021 Peter Dias
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package    core
+ */
+class linkedin extends openidconnect {
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer The issuer initialised with proper default values.
+     */
+    public static function init(): issuer {
+        $record = (object) [
+            'name' => 'LinkedIn',
+            'image' => 'https://static.licdn.com/scds/common/u/images/logos/favicons/v1/favicon.ico',
+            'baseurl' => 'https://www.linkedin.com/oauth', // The /oauth is where .well-known/openid-configuration lives.
+            'loginscopes' => 'openid profile email',
+            'loginscopesoffline' => 'openid profile email',
+            'showonloginpage' => issuer::EVERYWHERE,
+            'servicetype' => 'linkedin',
+        ];
+
+        $issuer = new issuer(0, $record);
+        return $issuer;
+    }
+}

lib/classes/oauth2/service/microsoft.php

@@ -0,0 +1,98 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\issuer;
+use core\oauth2\endpoint;
+use core\oauth2\user_field_mapping;
+use core\oauth2\discovery\openidconnect;
+
+/**
+ * Class for Microsoft oAuth service, with the specific methods related to it.
+ *
+ * @package    core
+ * @copyright  2021 Sara Arjona (sara@moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class microsoft extends openidconnect implements issuer_interface {
+
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer The issuer initialised with proper default values.
+     */
+    public static function init(): issuer {
+        $record = (object) [
+            'name' => 'Microsoft',
+            'image' => 'https://www.microsoft.com/favicon.ico',
+            'baseurl' => '',
+            'loginscopes' => 'openid profile email user.read',
+            'loginscopesoffline' => 'openid profile email user.read offline_access',
+            'showonloginpage' => issuer::EVERYWHERE,
+            'servicetype' => 'microsoft',
+        ];
+
+        $issuer = new issuer(0, $record);
+        return $issuer;
+    }
+
+    /**
+     * Create endpoints for this issuer.
+     *
+     * @param issuer $issuer Issuer the endpoints should be created for.
+     * @return issuer
+     */
+    public static function create_endpoints(issuer $issuer): issuer {
+        $endpoints = [
+            'authorization_endpoint' => 'https://login.microsoftonline.com/common/oauth2/v2.0/authorize',
+            'token_endpoint' => 'https://login.microsoftonline.com/common/oauth2/v2.0/token',
+            'userinfo_endpoint' => 'https://graph.microsoft.com/v1.0/me/',
+            'userpicture_endpoint' => 'https://graph.microsoft.com/v1.0/me/photo/$value',
+        ];
+        foreach ($endpoints as $name => $url) {
+            $record = (object) [
+                'issuerid' => $issuer->get('id'),
+                'name' => $name,
+                'url' => $url
+            ];
+            $endpoint = new endpoint(0, $record);
+            $endpoint->create();
+        }
+
+        // Create the field mappings.
+        $mapping = [
+            'givenName' => 'firstname',
+            'surname' => 'lastname',
+            'userPrincipalName' => 'email',
+            'displayName' => 'alternatename',
+            'officeLocation' => 'address',
+            'mobilePhone' => 'phone1',
+            'preferredLanguage' => 'lang'
+        ];
+        foreach ($mapping as $external => $internal) {
+            $record = (object) [
+                'issuerid' => $issuer->get('id'),
+                'externalfield' => $external,
+                'internalfield' => $internal
+            ];
+            $userfieldmapping = new user_field_mapping(0, $record);
+            $userfieldmapping->create();
+        }
+
+        return $issuer;
+    }
+}

lib/classes/oauth2/service/moodlenet.php

@@ -0,0 +1,189 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\http_client;
+use core\oauth2\discovery\auth_server_config_reader;
+use core\oauth2\endpoint;
+use core\oauth2\issuer;
+use GuzzleHttp\Psr7\Request;
+
+/**
+ * MoodleNet OAuth 2 configuration.
+ *
+ * @package    core
+ * @copyright  2023 Jake Dallimore <jrhdallimore@gmail.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class moodlenet implements issuer_interface {
+
+    /**
+     * Get the issuer template to display in the form.
+     *
+     * @return issuer the issuer.
+     */
+    public static function init(): ?issuer {
+        $record = (object) [
+            'name' => 'MoodleNet',
+            'image' => 'https://moodle.net/favicon.ico',
+            'baseurl' => 'https://moodle.net',
+            'loginscopes' => '',
+            'loginscopesoffline' => '',
+            'loginparamsoffline' => '',
+            'showonloginpage' => issuer::SERVICEONLY,
+            'servicetype' => 'moodlenet',
+        ];
+        $issuer = new issuer(0, $record);
+
+        return $issuer;
+    }
+
+    /**
+     * Create the endpoints for the issuer.
+     *
+     * @param issuer $issuer the issuer instance.
+     * @return issuer the issuer instance.
+     */
+    public static function create_endpoints(issuer $issuer): issuer {
+        self::discover_endpoints($issuer);
+        return $issuer;
+    }
+
+    /**
+     * Read the OAuth 2 Auth Server Metadata.
+     *
+     * @param issuer $issuer the issuer instance.
+     * @return int the number of endpoints created.
+     */
+    public static function discover_endpoints($issuer): int {
+        $baseurl = $issuer->get('baseurl');
+        if (empty($baseurl)) {
+            return 0;
+        }
+
+        $endpointscreated = 0;
+        $config = [];
+        if (defined('BEHAT_SITE_RUNNING')) {
+            $config['verify'] = false;
+        }
+        $configreader = new auth_server_config_reader(new http_client($config));
+        try {
+            $config = $configreader->read_configuration(new \moodle_url($baseurl));
+
+            foreach ($config as $key => $value) {
+                if (substr_compare($key, '_endpoint', -strlen('_endpoint')) === 0) {
+                    $record = new \stdClass();
+                    $record->issuerid = $issuer->get('id');
+                    $record->name = $key;
+                    $record->url = $value;
+
+                    $endpoint = new endpoint(0, $record);
+                    $endpoint->create();
+                    $endpointscreated++;
+                }
+
+                if ($key == 'scopes_supported') {
+                    $issuer->set('scopessupported', implode(' ', $value));
+                    $issuer->update();
+                }
+            }
+        } catch (\Exception $e) {
+            throw new \moodle_exception('Could not read service configuration for issuer: ' . $issuer->get('name'));
+        }
+
+        try {
+            self::client_registration($issuer);
+        } catch (\Exception $e) {
+            throw new \moodle_exception('Could not register client for issuer: ' . $issuer->get('name'));
+        }
+
+        return $endpointscreated;
+    }
+
+    /**
+     * Perform (open) OAuth 2 Dynamic Client Registration with the MoodleNet application.
+     *
+     * @param issuer $issuer the issuer instance containing the service baseurl.
+     * @return void
+     */
+    protected static function client_registration(issuer $issuer): void {
+        global $CFG, $SITE;
+
+        $clientid = $issuer->get('clientid');
+        $clientsecret = $issuer->get('clientsecret');
+
+        if (empty($clientid) && empty($clientsecret)) {
+            $url = $issuer->get_endpoint_url('registration');
+            if ($url) {
+                $scopes = str_replace("\r", " ", $issuer->get('scopessupported'));
+                $hosturl = $CFG->wwwroot;
+
+                $request = [
+                    'client_name' => $SITE->fullname,
+                    'client_uri' => $hosturl,
+                    'logo_uri' => $hosturl . '/pix/moodlelogo.png',
+                    'tos_uri' => $hosturl,
+                    'policy_uri' => $hosturl,
+                    'software_id' => 'moodle',
+                    'software_version' => $CFG->version,
+                    'redirect_uris' => [
+                        $hosturl . '/admin/oauth2callback.php'
+                    ],
+                    'token_endpoint_auth_method' => 'client_secret_basic',
+                    'grant_types' => [
+                        'authorization_code',
+                        'refresh_token'
+                    ],
+                    'response_types' => [
+                        'code'
+                    ],
+                    'scope' => $scopes
+                ];
+
+                $config = [];
+                if (defined('BEHAT_SITE_RUNNING')) {
+                    $config['verify'] = false;
+                }
+                $client = new http_client($config);
+                $request = new Request(
+                    'POST',
+                    $url,
+                    [
+                        'Content-type' => 'application/json',
+                        'Accept' => 'application/json',
+                    ],
+                    json_encode($request)
+                );
+
+                try {
+                    $response = $client->send($request);
+                    $responsebody = $response->getBody()->getContents();
+                    $decodedbody = json_decode($responsebody, true);
+                    if (is_null($decodedbody)) {
+                        throw new \moodle_exception('Error: ' . __METHOD__ . ': Failed to decode response body. Invalid JSON.');
+                    }
+                    $issuer->set('clientid', $decodedbody['client_id']);
+                    $issuer->set('clientsecret', $decodedbody['client_secret']);
+                    $issuer->update();
+                } catch (\Exception $e) {
+                    $msg = "Could not self-register {$issuer->get('name')}. Wrong URL or JSON data [URL: $url]";
+                    throw new \moodle_exception($msg);
+                }
+            }
+        }
+    }
+}

lib/classes/oauth2/service/nextcloud.php

@@ -0,0 +1,100 @@
+<?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/>.
+
+namespace core\oauth2\service;
+
+use core\oauth2\issuer;
+use core\oauth2\endpoint;
+use core\oauth2\user_field_mapping;
+use core\oauth2\discovery\openidconnect;
+
+/**
+ * Class for Nextcloud oAuth service, with the specific methods related to it.
+ *
+ * @package    core
+ * @copyright  2021 Sara Arjona (sara@moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class nextcloud extends openidconnect implements issuer_interface {
+
+    /**
+     * Build an OAuth2 issuer, with all the default values for this service.
+     *
+     * @return issuer The issuer initialised with proper default values.
+     */
+    public static function init(): issuer {
+        $record = (object) [
+            'name' => 'Nextcloud',
+            'image' => 'https://nextcloud.com/wp-content/uploads/2022/03/favicon.png',
+            'basicauth' => 1,
+            'servicetype' => 'nextcloud',
+        ];
+
+        $issuer = new issuer(0, $record);
+
+        return $issuer;
+    }
+
+    /**
+     * Create endpoints for this issuer.
+     *
+     * @param issuer $issuer Issuer the endpoints should be created for.
+     * @return issuer
+     */
+    public static function create_endpoints(issuer $issuer): issuer {
+        // Nextcloud has a custom baseurl. Thus, the creation of endpoints has to be done later.
+        $baseurl = $issuer->get('baseurl');
+        // Add trailing slash to baseurl, if needed.
+        if (substr($baseurl, -1) !== '/') {
+            $baseurl .= '/';
+        }
+
+        $endpoints = [
+            // Baseurl will be prepended later.
+            'authorization_endpoint' => 'index.php/apps/oauth2/authorize',
+            'token_endpoint' => 'index.php/apps/oauth2/api/v1/token',
+            'userinfo_endpoint' => 'ocs/v2.php/cloud/user?format=json',
+            'webdav_endpoint' => 'remote.php/webdav/',
+            'ocs_endpoint' => 'ocs/v1.php/apps/files_sharing/api/v1/shares',
+        ];
+
+        foreach ($endpoints as $name => $url) {
+            $record = (object) [
+                'issuerid' => $issuer->get('id'),
+                'name' => $name,
+                'url' => $baseurl . $url,
+            ];
+            $endpoint = new \core\oauth2\endpoint(0, $record);
+            $endpoint->create();
+        }
+
+        // Create the field mappings.
+        $mapping = [
+            'ocs-data-email' => 'email',
+            'ocs-data-id' => 'username',
+        ];
+        foreach ($mapping as $external => $internal) {
+            $record = (object) [
+                'issuerid' => $issuer->get('id'),
+                'externalfield' => $external,
+                'internalfield' => $internal
+            ];
+            $userfieldmapping = new \core\oauth2\user_field_mapping(0, $record);
+            $userfieldmapping->create();
+        }
+        return $issuer;
+    }
+}