Your IP : 192.168.165.1
<?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/>.
/**
* Search area base class for areas working at module level.
*
* @package core_search
* @copyright 2015 David Monllao {@link http://www.davidmonllao.com}
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
namespace core_search;
defined('MOODLE_INTERNAL') || die();
/**
* Base implementation for search areas working at module level.
*
* Even if the search area works at multiple levels, if module is one of these levels
* it should extend this class, as this class provides helper methods for module level search management.
*
* @package core_search
* @copyright 2015 David Monllao {@link http://www.davidmonllao.com}
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
abstract class base_mod extends base {
/**
* The context levels the search area is working on.
*
* This can be overwriten by the search area if it works at multiple
* levels.
*
* @var array
*/
protected static $levels = [CONTEXT_MODULE];
/**
* Returns the module name.
*
* @return string
*/
protected function get_module_name() {
return substr($this->componentname, 4);
}
/**
* Gets the course module for the required instanceid + modulename.
*
* The returned data depends on the logged user, when calling this through
* self::get_document the admin user is used so everything would be returned.
*
* No need more internal caching here, modinfo is already cached.
*
* @throws \dml_missing_record_exception
* @param string $modulename The module name
* @param int $instanceid Module instance id (depends on the module)
* @param int $courseid Helps speeding up things
* @return \cm_info
*/
protected function get_cm($modulename, $instanceid, $courseid) {
$modinfo = get_fast_modinfo($courseid);
// Hopefully not many, they are indexed by cmid.
$instances = $modinfo->get_instances_of($modulename);
foreach ($instances as $cminfo) {
if ($cminfo->instance == $instanceid) {
return $cminfo;
}
}
// Nothing found.
throw new \dml_missing_record_exception($modulename);
}
/**
* Helper function that gets SQL useful for restricting a search query given a passed-in
* context.
*
* The SQL returned will be zero or more JOIN statements, surrounded by whitespace, which act
* as restrictions on the query based on the rows in a module table.
*
* You can pass in a null or system context, which will both return an empty string and no
* params.
*
* Returns an array with two nulls if there can be no results for the activity within this
* context (e.g. it is a block context).
*
* If named parameters are used, these will be named gcrs0, gcrs1, etc. The table aliases used
* in SQL also all begin with gcrs, to avoid conflicts.
*
* @param \context|null $context Context to restrict the query
* @param string $modname Name of module e.g. 'forum'
* @param string $modtable Alias of table containing module id
* @param int $paramtype Type of SQL parameters to use (default question mark)
* @return array Array with SQL and parameters; both null if no need to query
* @throws \coding_exception If called with invalid params
*/
protected function get_context_restriction_sql(\context $context = null, $modname, $modtable,
$paramtype = SQL_PARAMS_QM) {
global $DB;
if (!$context) {
return ['', []];
}
switch ($paramtype) {
case SQL_PARAMS_QM:
$param1 = '?';
$param2 = '?';
$param3 = '?';
$key1 = 0;
$key2 = 1;
$key3 = 2;
break;
case SQL_PARAMS_NAMED:
$param1 = ':gcrs0';
$param2 = ':gcrs1';
$param3 = ':gcrs2';
$key1 = 'gcrs0';
$key2 = 'gcrs1';
$key3 = 'gcrs2';
break;
default:
throw new \coding_exception('Unexpected $paramtype: ' . $paramtype);
}
$params = [];
switch ($context->contextlevel) {
case CONTEXT_SYSTEM:
$sql = '';
break;
case CONTEXT_COURSECAT:
// Find all activities of this type within the specified category or any
// sub-category.
$pathmatch = $DB->sql_like('gcrscc2.path', $DB->sql_concat('gcrscc1.path', $param3));
$sql = " JOIN {course_modules} gcrscm ON gcrscm.instance = $modtable.id
AND gcrscm.module = (SELECT id FROM {modules} WHERE name = $param1)
JOIN {course} gcrsc ON gcrsc.id = gcrscm.course
JOIN {course_categories} gcrscc1 ON gcrscc1.id = $param2
JOIN {course_categories} gcrscc2 ON gcrscc2.id = gcrsc.category AND
(gcrscc2.id = gcrscc1.id OR $pathmatch) ";
$params[$key1] = $modname;
$params[$key2] = $context->instanceid;
// Note: This param is a bit annoying as it obviously never changes, but sql_like
// throws a debug warning if you pass it anything with quotes in, so it has to be
// a bound parameter.
$params[$key3] = '/%';
break;
case CONTEXT_COURSE:
// Find all activities of this type within the course.
$sql = " JOIN {course_modules} gcrscm ON gcrscm.instance = $modtable.id
AND gcrscm.course = $param1
AND gcrscm.module = (SELECT id FROM {modules} WHERE name = $param2) ";
$params[$key1] = $context->instanceid;
$params[$key2] = $modname;
break;
case CONTEXT_MODULE:
// Find only the specified activity of this type.
$sql = " JOIN {course_modules} gcrscm ON gcrscm.instance = $modtable.id
AND gcrscm.id = $param1
AND gcrscm.module = (SELECT id FROM {modules} WHERE name = $param2) ";
$params[$key1] = $context->instanceid;
$params[$key2] = $modname;
break;
case CONTEXT_BLOCK:
case CONTEXT_USER:
// These contexts cannot contain any activities, so return null.
return [null, null];
default:
throw new \coding_exception('Unexpected contextlevel: ' . $context->contextlevel);
}
return [$sql, $params];
}
/**
* This can be used in subclasses to change ordering within the get_contexts_to_reindex
* function.
*
* It returns 2 values:
* - Extra SQL joins (tables course_modules 'cm' and context 'x' already exist).
* - An ORDER BY value which must use aggregate functions, by default 'MAX(cm.added) DESC'.
*
* Note the query already includes a GROUP BY on the context fields, so if your joins result
* in multiple rows, you can use aggregate functions in the ORDER BY. See forum for an example.
*
* @return string[] Array with 2 elements; extra joins for the query, and ORDER BY value
*/
protected function get_contexts_to_reindex_extra_sql() {
return ['', 'MAX(cm.added) DESC'];
}
/**
* Gets a list of all contexts to reindex when reindexing this search area.
*
* For modules, the default is to return all contexts for modules of that type, in order of
* time added (most recent first).
*
* @return \Iterator Iterator of contexts to reindex
* @throws \moodle_exception If any DB error
*/
public function get_contexts_to_reindex() {
global $DB;
list ($extrajoins, $dborder) = $this->get_contexts_to_reindex_extra_sql();
$contexts = [];
$selectcolumns = \context_helper::get_preload_record_columns_sql('x');
$groupbycolumns = '';
foreach (\context_helper::get_preload_record_columns('x') as $column => $thing) {
if ($groupbycolumns !== '') {
$groupbycolumns .= ',';
}
$groupbycolumns .= $column;
}
$rs = $DB->get_recordset_sql("
SELECT $selectcolumns
FROM {course_modules} cm
JOIN {context} x ON x.instanceid = cm.id AND x.contextlevel = ?
$extrajoins
WHERE cm.module = (SELECT id FROM {modules} WHERE name = ?)
GROUP BY $groupbycolumns
ORDER BY $dborder", [CONTEXT_MODULE, $this->get_module_name()]);
return new \core\dml\recordset_walk($rs, function($rec) {
$id = $rec->ctxid;
\context_helper::preload_from_record($rec);
return \context::instance_by_id($id);
});
}
/**
* Indicates whether this search area may restrict access by group.
*
* This should return true if the search area (sometimes) sets the 'groupid' schema field, and
* false if it never sets that field.
*
* (If this function returns false, but the field is set, then results may be restricted
* unintentionally.)
*
* If this returns true, the search engine will automatically apply group restrictions in some
* cases (by default, where a module is configured to use separate groups). See function
* restrict_cm_access_by_group().
*
* @return bool
*/
public function supports_group_restriction() {
return false;
}
/**
* Checks whether the content of this search area should be restricted by group for a
* specific module. Called at query time.
*
* The default behaviour simply checks if the effective group mode is SEPARATEGROUPS, which
* is probably correct for most cases.
*
* If restricted by group, the search query will (where supported by the engine) filter out
* results for groups the user does not belong to, unless the user has 'access all groups'
* for the activity. This affects only documents which set the 'groupid' field; results with no
* groupid will not be restricted.
*
* Even if you return true to this function, you may still need to do group access checks in
* check_access, because the search engine may not support group restrictions.
*
* @param \cm_info $cm
* @return bool True to restrict by group
*/
public function restrict_cm_access_by_group(\cm_info $cm) {
return $cm->effectivegroupmode == SEPARATEGROUPS;
}
/**
* Returns an icon instance for the document.
*
* @param \core_search\document $doc
* @return \core_search\document_icon
*/
public function get_doc_icon(document $doc) : document_icon {
return new document_icon('icon', $this->get_module_name());
}
/**
* Returns a list of category names associated with the area.
*
* @return array
*/
public function get_category_names() {
return [manager::SEARCH_AREA_CATEGORY_COURSE_CONTENT];
}
}