private static function create_endpoints_for_facebook($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',
            'link',
            '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.
        $mapping = [
            'name' => 'alternatename',
            'last_name' => 'lastname',
            'email' => 'email',
            'first_name' => 'firstname',
            'picture-data-url' => 'picture',
            'link' => 'url',
        ];
        foreach ($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;
    }