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See Release Notes

  • Bug fixes for general core bugs in 3.10.x will end 8 November 2021 (12 months).
  • Bug fixes for security issues in 3.10.x will end 9 May 2022 (18 months).
  • PHP version: minimum PHP 7.2.0 Note: minimum PHP version has increased since Moodle 3.8. PHP 7.3.x and 7.4.x are supported too.
<?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 the parent class for moodle blocks, block_base.
 *
 * @package    core_block
 * @license    http://www.gnu.org/copyleft/gpl.html GNU Public License
 */

/// Constants

/**
 * Block type of list. Contents of block should be set as an associative array in the content object as items ($this->content->items). Optionally include footer text in $this->content->footer.
 */
define('BLOCK_TYPE_LIST',    1);

/**
 * Block type of text. Contents of block should be set to standard html text in the content object as items ($this->content->text). Optionally include footer text in $this->content->footer.
 */
define('BLOCK_TYPE_TEXT',    2);
/**
 * Block type of tree. $this->content->items is a list of tree_item objects and $this->content->footer is a string.
 */
define('BLOCK_TYPE_TREE',    3);

/**
 * Class for describing a moodle block, all Moodle blocks derive from this class
 *
 * @author Jon Papaioannou
 * @package core_block
 */
class block_base {

    /**
     * Internal var for storing/caching translated strings
     * @var string $str
     */
    var $str;

    /**
     * The title of the block to be displayed in the block title area.
     * @var string $title
     */
    var $title         = NULL;

    /**
     * The name of the block to be displayed in the block title area if the title is empty.
     * @var string arialabel
     */
    var $arialabel         = NULL;

    /**
     * The type of content that this block creates. Currently support options - BLOCK_TYPE_LIST, BLOCK_TYPE_TEXT
     * @var int $content_type
     */
    var $content_type  = BLOCK_TYPE_TEXT;

    /**
     * An object to contain the information to be displayed in the block.
< * @var stdObject $content
> * @var stdClass $content
*/ var $content = NULL; /** * The initialized instance of this block object.
< * @var block $instance
> * @var stdClass $instance
*/ var $instance = NULL; /** * The page that this block is appearing on. * @var moodle_page */ public $page = NULL; /** * This blocks's context.
< * @var stdClass
> * @var context
*/ public $context = NULL; /** * An object containing the instance configuration information for the current instance of this block.
< * @var stdObject $config
> * @var stdClass $config
*/ var $config = NULL; /** * How often the cronjob should run, 0 if not at all. * @var int $cron */ var $cron = NULL; /// Class Functions /** * Fake constructor to keep PHP5 happy * */ function __construct() { $this->init(); } /** * Function that can be overridden to do extra cleanup before * the database tables are deleted. (Called once per block, not per instance!) */ function before_delete() { } /** * Returns the block name, as present in the class name, * the database, the block directory, etc etc. * * @return string */ function name() { // Returns the block name, as present in the class name, // the database, the block directory, etc etc.
< static $myname; < if ($myname === NULL) {
$myname = strtolower(get_class($this));
< $myname = substr($myname, strpos($myname, '_') + 1); < } < return $myname;
> return substr($myname, strpos($myname, '_') + 1);
} /** * Parent class version of this function simply returns NULL * This should be implemented by the derived class to return * the content object. * * @return stdObject */ function get_content() { // This should be implemented by the derived class. return NULL; } /** * Returns the class $title var value. * * Intentionally doesn't check if a title is set. * This is already done in {@link _self_test()} * * @return string $this->title */ function get_title() { // Intentionally doesn't check if a title is set. This is already done in _self_test() return $this->title; } /** * Returns the class $content_type var value. * * Intentionally doesn't check if content_type is set. * This is already done in {@link _self_test()} * * @return string $this->content_type */ function get_content_type() { // Intentionally doesn't check if a content_type is set. This is already done in _self_test() return $this->content_type; } /** * Returns true or false, depending on whether this block has any content to display * and whether the user has permission to view the block * * @return boolean */ function is_empty() { if ( !has_capability('moodle/block:view', $this->context) ) { return true; } $this->get_content(); return(empty($this->content->text) && empty($this->content->footer)); } /** * First sets the current value of $this->content to NULL * then calls the block's {@link get_content()} function * to set its value back. * * @return stdObject */ function refresh_content() { // Nothing special here, depends on content() $this->content = NULL; return $this->get_content(); } /** * Return a block_contents object representing the full contents of this block. * * This internally calls ->get_content(), and then adds the editing controls etc. * * You probably should not override this method, but instead override * {@link html_attributes()}, {@link formatted_contents()} or {@link get_content()}, * {@link hide_header()}, {@link (get_edit_controls)}, etc. * * @return block_contents a representation of the block, for rendering. * @since Moodle 2.0. */ public function get_content_for_output($output) { global $CFG; // We can exit early if the current user doesn't have the capability to view the block. if (!has_capability('moodle/block:view', $this->context)) { return null; } $bc = new block_contents($this->html_attributes()); $bc->attributes['data-block'] = $this->name(); $bc->blockinstanceid = $this->instance->id; $bc->blockpositionid = $this->instance->blockpositionid; if ($this->instance->visible) { $bc->content = $this->formatted_contents($output); if (!empty($this->content->footer)) { $bc->footer = $this->content->footer; } } else { $bc->add_class('invisibleblock'); } if (!$this->hide_header()) { $bc->title = $this->title; } if (empty($bc->title)) { $bc->arialabel = new lang_string('pluginname', get_class($this)); $this->arialabel = $bc->arialabel; }
< if ($this->page->user_is_editing()) {
> if ($this->page->user_is_editing() && $this->instance_can_be_edited()) {
$bc->controls = $this->page->blocks->edit_controls($this); } else { // we must not use is_empty on hidden blocks if ($this->is_empty() && !$bc->controls) { return null; } } if (empty($CFG->allowuserblockhiding) || (empty($bc->content) && empty($bc->footer)) || !$this->instance_can_be_collapsed()) { $bc->collapsible = block_contents::NOT_HIDEABLE; } else if (get_user_preferences('block' . $bc->blockinstanceid . 'hidden', false)) { $bc->collapsible = block_contents::HIDDEN; } else { $bc->collapsible = block_contents::VISIBLE; } if ($this->instance_can_be_docked() && !$this->hide_header()) { $bc->dockable = true; } $bc->annotation = ''; // TODO MDL-19398 need to work out what to say here. return $bc; } /** * Return an object containing all the block content to be returned by external functions. * * If your block is returning formatted content or provide files for download, you should override this method to use the
< * external_format_text, external_format_string functions for formatting or external_util::get_area_files for files.
> * \core_external\util::format_text, \core_external\util::format_string functions for formatting or external_util::get_area_files for files.
* * @param core_renderer $output the rendered used for output * @return stdClass object containing the block title, central content, footer and linked files (if any). * @since Moodle 3.6 */ public function get_content_for_external($output) { $bc = new stdClass; $bc->title = null; $bc->content = null; $bc->contentformat = FORMAT_HTML; $bc->footer = null; $bc->files = []; if ($this->instance->visible) { $bc->content = $this->formatted_contents($output); if (!empty($this->content->footer)) { $bc->footer = $this->content->footer; } } if (!$this->hide_header()) { $bc->title = $this->title; } return $bc; } /** * Return the plugin config settings for external functions. * * In some cases the configs will need formatting or be returned only if the current user has some capabilities enabled. * * @return stdClass the configs for both the block instance and plugin (as object with name -> value) * @since Moodle 3.8 */ public function get_config_for_external() { return (object) [ 'instance' => new stdClass(), 'plugin' => new stdClass(), ]; } /** * Convert the contents of the block to HTML. * * This is used by block base classes like block_list to convert the structured * $this->content->list and $this->content->icons arrays to HTML. So, in most * blocks, you probaby want to override the {@link get_contents()} method, * which generates that structured representation of the contents. * * @param $output The core_renderer to use when generating the output. * @return string the HTML that should appearn in the body of the block. * @since Moodle 2.0. */ protected function formatted_contents($output) { $this->get_content(); $this->get_required_javascript(); if (!empty($this->content->text)) { return $this->content->text; } else { return ''; } } /** * Tests if this block has been implemented correctly. * Also, $errors isn't used right now * * @return boolean */ function _self_test() { // Tests if this block has been implemented correctly. // Also, $errors isn't used right now $errors = array(); $correct = true; if ($this->get_title() === NULL) { $errors[] = 'title_not_set'; $correct = false; } if (!in_array($this->get_content_type(), array(BLOCK_TYPE_LIST, BLOCK_TYPE_TEXT, BLOCK_TYPE_TREE))) { $errors[] = 'invalid_content_type'; $correct = false; } //following selftest was not working when roles&capabilities were used from block /* if ($this->get_content() === NULL) { $errors[] = 'content_not_set'; $correct = false; }*/ $formats = $this->applicable_formats(); if (empty($formats) || array_sum($formats) === 0) { $errors[] = 'no_formats'; $correct = false; } return $correct; } /** * Subclasses should override this and return true if the * subclass block has a settings.php file. * * @return boolean */ function has_config() { return false; } /** * Default behavior: save all variables as $CFG properties * You don't need to override this if you 're satisfied with the above * * @deprecated since Moodle 2.9 MDL-49385 - Please use Admin Settings functionality to save block configuration. */ function config_save($data) { throw new coding_exception('config_save() can not be used any more, use Admin Settings functionality to save block configuration.'); } /** * Which page types this block may appear on. * * The information returned here is processed by the * {@link blocks_name_allowed_in_format()} function. Look there if you need * to know exactly how this works. * * Default case: everything except mod and tag. * * @return array page-type prefix => true/false. */ function applicable_formats() { // Default case: the block can be used in courses and site index, but not in activities return array('all' => true, 'mod' => false, 'tag' => false); } /** * Default return is false - header will be shown * @return boolean */ function hide_header() { return false; } /** * Return any HTML attributes that you want added to the outer <div> that * of the block when it is output. * * Because of the way certain JS events are wired it is a good idea to ensure * that the default values here still get set. * I found the easiest way to do this and still set anything you want is to * override it within your block in the following way * * <code php> * function html_attributes() { * $attributes = parent::html_attributes(); * $attributes['class'] .= ' mynewclass'; * return $attributes; * } * </code> * * @return array attribute name => value. */ function html_attributes() { $attributes = array( 'id' => 'inst' . $this->instance->id, 'class' => 'block_' . $this->name() . ' block', 'role' => $this->get_aria_role() ); if ($this->hide_header()) { $attributes['class'] .= ' no-header'; } if ($this->instance_can_be_docked() && get_user_preferences('docked_block_instance_' . $this->instance->id, 0)) { $attributes['class'] .= ' dock_on_load'; } return $attributes; } /** * Set up a particular instance of this class given data from the block_insances * table and the current page. (See {@link block_manager::load_blocks()}.) * * @param stdClass $instance data from block_insances, block_positions, etc.
< * @param moodle_page $the page this block is on.
> * @param moodle_page $page the page this block is on.
*/ function _load_instance($instance, $page) { if (!empty($instance->configdata)) { $this->config = unserialize_object(base64_decode($instance->configdata)); } $this->instance = $instance; $this->context = context_block::instance($instance->id); $this->page = $page; $this->specialization(); } /** * Allows the block to load any JS it requires into the page. * * By default this function simply permits the user to dock the block if it is dockable. * * Left null as of MDL-64506. */ function get_required_javascript() { } /** * This function is called on your subclass right after an instance is loaded * Use this function to act on instance data just after it's loaded and before anything else is done * For instance: if your block will have different title's depending on location (site, course, blog, etc) */ function specialization() { // Just to make sure that this method exists. } /** * Is each block of this type going to have instance-specific configuration? * Normally, this setting is controlled by {@link instance_allow_multiple()}: if multiple * instances are allowed, then each will surely need its own configuration. However, in some * cases it may be necessary to provide instance configuration to blocks that do not want to * allow multiple instances. In that case, make this function return true. * I stress again that this makes a difference ONLY if {@link instance_allow_multiple()} returns false. * @return boolean */ function instance_allow_config() { return false; } /** * Are you going to allow multiple instances of each block? * If yes, then it is assumed that the block WILL USE per-instance configuration * @return boolean */ function instance_allow_multiple() { // Are you going to allow multiple instances of each block? // If yes, then it is assumed that the block WILL USE per-instance configuration return false; } /** * Serialize and store config data */ function instance_config_save($data, $nolongerused = false) { global $DB; $DB->update_record('block_instances', ['id' => $this->instance->id, 'configdata' => base64_encode(serialize($data)), 'timemodified' => time()]); } /** * Replace the instance's configuration data with those currently in $this->config; */ function instance_config_commit($nolongerused = false) { global $DB; $this->instance_config_save($this->config); } /** * Do any additional initialization you may need at the time a new block instance is created * @return boolean */ function instance_create() { return true; } /** * Copy any block-specific data when copying to a new block instance. * @param int $fromid the id number of the block instance to copy from * @return boolean */ public function instance_copy($fromid) { return true; } /** * Delete everything related to this instance if you have been using persistent storage other than the configdata field. * @return boolean */ function instance_delete() { return true; } /** * Allows the block class to have a say in the user's ability to edit (i.e., configure) blocks of this type. * The framework has first say in whether this will be allowed (e.g., no editing allowed unless in edit mode) * but if the framework does allow it, the block can still decide to refuse. * @return boolean */ function user_can_edit() { global $USER; if (has_capability('moodle/block:edit', $this->context)) { return true; } // The blocks in My Moodle are a special case. We want them to inherit from the user context. if (!empty($USER->id) && $this->instance->parentcontextid == $this->page->context->id // Block belongs to this page && $this->page->context->contextlevel == CONTEXT_USER // Page belongs to a user && $this->page->context->instanceid == $USER->id) { // Page belongs to this user return has_capability('moodle/my:manageblocks', $this->page->context); } return false; } /** * Allows the block class to have a say in the user's ability to create new instances of this block. * The framework has first say in whether this will be allowed (e.g., no adding allowed unless in edit mode) * but if the framework does allow it, the block can still decide to refuse. * This function has access to the complete page object, the creation related to which is being determined. * * @param moodle_page $page * @return boolean */ function user_can_addto($page) {
> global $CFG; // List of formats this block supports. > require_once($CFG->dirroot . '/user/lib.php'); $formats = $this->applicable_formats(); >
> // Check if user is trying to add blocks to their profile page. // The blocks in My Moodle are a special case and use a different capability. > $userpagetypes = user_page_type_list($page->pagetype, null, null); $mypagetypes = my_page_type_list($page->pagetype); // Get list of possible my page types. > if (array_key_exists($page->pagetype, $userpagetypes)) { > $capability = 'block/' . $this->name() . ':addinstance'; if (array_key_exists($page->pagetype, $mypagetypes)) { // Ensure we are on a page with a my page type. > return $this->has_add_block_capability($page, $capability) // If the block cannot be displayed on /my it is ok if the myaddinstance capability is not defined. > && has_capability('moodle/user:manageownblocks', $page->context); // Is 'my' explicitly forbidden? > } // If 'all' has not been allowed, has 'my' been explicitly allowed? >
if ((isset($formats['my']) && $formats['my'] == false) || (empty($formats['all']) && empty($formats['my']))) { // Block cannot be added to /my regardless of capabilities. return false; } else { $capability = 'block/' . $this->name() . ':myaddinstance'; return $this->has_add_block_capability($page, $capability) && has_capability('moodle/my:manageblocks', $page->context); } } // Check if this is a block only used on /my. unset($formats['my']); if (empty($formats)) { // Block can only be added to /my - return false. return false; } $capability = 'block/' . $this->name() . ':addinstance'; if ($this->has_add_block_capability($page, $capability) && has_capability('moodle/block:edit', $page->context)) { return true; } return false; } /** * Returns true if the user can add a block to a page. * * @param moodle_page $page * @param string $capability the capability to check * @return boolean true if user can add a block, false otherwise. */ private function has_add_block_capability($page, $capability) { // Check if the capability exists. if (!get_capability_info($capability)) { // Debug warning that the capability does not exist, but no more than once per page. static $warned = array(); if (!isset($warned[$this->name()])) { debugging('The block ' .$this->name() . ' does not define the standard capability ' . $capability , DEBUG_DEVELOPER); $warned[$this->name()] = 1; } // If the capability does not exist, the block can always be added. return true; } else { return has_capability($capability, $page->context); } } static function get_extra_capabilities() { return array('moodle/block:view', 'moodle/block:edit'); } /** * Can be overridden by the block to prevent the block from being dockable. * * @return bool * * Return false as per MDL-64506 */ public function instance_can_be_docked() { return false; } /** * If overridden and set to false by the block it will not be hidable when * editing is turned on. * * @return bool */ public function instance_can_be_hidden() { return true; } /** * If overridden and set to false by the block it will not be collapsible. * * @return bool */ public function instance_can_be_collapsed() { return true; }
> /** /** @callback callback functions for comments api */ > * If overridden and set to false by the block it will not be editable. public static function comment_template($options) { > * $ret = <<<EOD > * @return bool <div class="comment-userpicture">___picture___</div> > */ <div class="comment-content"> > public function instance_can_be_edited() { ___name___ - <span>___time___</span> > return true; <div>___content___</div> > } </div> >
EOD; return $ret; } public static function comment_permissions($options) { return array('view'=>true, 'post'=>true); } public static function comment_url($options) { return null; } public static function comment_display($comments, $options) { return $comments; } public static function comment_add(&$comments, $options) { return true; } /** * Returns the aria role attribute that best describes this block. * * Region is the default, but this should be overridden by a block is there is a region child, or even better * a landmark child. * * Options are as follows: * - landmark * - application * - banner * - complementary * - contentinfo * - form * - main * - navigation * - search * * @return string */ public function get_aria_role() { return 'complementary'; }
> } > /** > * This method can be overriden to add some extra checks to decide whether the block can be added or not to a page. /** > * It doesn't need to do the standard capability checks as they will be performed by has_add_block_capability(). * Specialized class for displaying a block with a list of icons/text labels > * This method is user agnostic. If you want to check if a user can add a block or not, you should use user_can_addto(). * > * * The get_content method should set $this->content->items and (optionally) > * @param moodle_page $page The page where this block will be added. * $this->content->icons, instead of $this->content->text. > * @return bool Whether the block can be added or not to the given page. * > */ * @author Jon Papaioannou > public function can_block_be_added(moodle_page $page): bool { * @package core_block > return true; */ > }
class block_list extends block_base { var $content_type = BLOCK_TYPE_LIST; function is_empty() { if ( !has_capability('moodle/block:view', $this->context) ) { return true; } $this->get_content(); return (empty($this->content->items) && empty($this->content->footer)); } protected function formatted_contents($output) { $this->get_content(); $this->get_required_javascript(); if (!empty($this->content->items)) { return $output->list_block_contents($this->content->icons, $this->content->items); } else { return ''; } } function html_attributes() { $attributes = parent::html_attributes(); $attributes['class'] .= ' list_block'; return $attributes; } } /** * Specialized class for displaying a tree menu. * * The {@link get_content()} method involves setting the content of * <code>$this->content->items</code> with an array of {@link tree_item} * objects (these are the top-level nodes). The {@link tree_item::children} * property may contain more tree_item objects, and so on. The tree_item class * itself is abstract and not intended for use, use one of it's subclasses. * * Unlike {@link block_list}, the icons are specified as part of the items, * not in a separate array. * * @author Alan Trick * @package core_block * @internal this extends block_list so we get is_empty() for free */ class block_tree extends block_list { /** * @var int specifies the manner in which contents should be added to this * block type. In this case <code>$this->content->items</code> is used with * {@link tree_item}s. */ public $content_type = BLOCK_TYPE_TREE; /** * Make the formatted HTML ouput. * * Also adds the required javascript call to the page output. * * @param core_renderer $output * @return string HTML */ protected function formatted_contents($output) { // based of code in admin_tree global $PAGE; // TODO change this when there is a proper way for blocks to get stuff into head. static $eventattached; if ($eventattached===null) { $eventattached = true; } if (!$this->content) { $this->content = new stdClass; $this->content->items = array(); } $this->get_required_javascript(); $this->get_content(); $content = $output->tree_block_contents($this->content->items,array('class'=>'block_tree list'));
< if (isset($this->id) && !is_numeric($this->id)) { < $content = $output->box($content, 'block_tree_box', $this->id); < }
return $content; } }