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1581 lines
58 KiB
PHP
1581 lines
58 KiB
PHP
<?php
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// This file is part of Moodle - http://moodle.org/
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//
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// Moodle is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// Moodle is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
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/**
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* Moodle tag library
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*
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* Tag strings : you can use any character in tags, except the comma (which is the separator) and
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* the '\' (backslash). Note that many spaces (or other blank characters) will get "compressed"
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* into one. A tag string is always a rawurlencode'd string. This is the same behavior as
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* http://del.icio.us.
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*
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* A "record" is a php array (note that an object will work too) that contains the following
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* variables :
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* - type: The database table containing the record that we are tagging (eg: for a blog, this is
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* the table named 'post', and for a user it is the table name 'user')
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* - id: The id of the record
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*
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* BASIC INSTRUCTIONS :
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* - to "tag a blog post" (for example):
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* tag_set('post', $blog_post->id, $array_of_tags, 'core', $thecontext);
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*
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* - to "remove all the tags on a blog post":
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* tag_set('post', $blog_post->id, array(), 'core', $thecontext);
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*
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* Tag set will create tags that need to be created.
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*
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* @package core_tag
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* @category tag
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* @todo MDL-31090 turn this into a full-fledged categorization system. This could start by
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* modifying (removing, probably) the 'tag type' to use another table describing the
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* relationship between tags (parents, sibling, etc.), which could then be merged with
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* the 'course categorization' system.
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* @see http://www.php.net/manual/en/function.urlencode.php
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* @copyright 2007 Luiz Cruz <luiz.laydner@gmail.com>
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* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
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*/
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/**
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* Used to require that the return value from a function is an array.
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* @see tag_set()
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*/
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define('TAG_RETURN_ARRAY', 0);
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/**
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* Used to require that the return value from a function is an object.
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* @see tag_set()
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*/
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define('TAG_RETURN_OBJECT', 1);
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/**
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* Use to specify that HTML free text is expected to be returned from a function.
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* @see tag_display_name()
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*/
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define('TAG_RETURN_TEXT', 2);
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/**
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* Use to specify that encoded HTML is expected to be returned from a function.
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* @see tag_display_name()
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*/
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define('TAG_RETURN_HTML', 3);
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/**
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* Used to specify that we wish a lowercased string to be returned
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* @see tag_normal()
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*/
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define('TAG_CASE_LOWER', 0);
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/**
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* Used to specify that we do not wish the case of the returned string to change
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* @see tag_normal()
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*/
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define('TAG_CASE_ORIGINAL', 1);
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/**
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* Used to specify that we want all related tags returned, no matter how they are related.
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* @see tag_get_related_tags()
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*/
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define('TAG_RELATED_ALL', 0);
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/**
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* Used to specify that we only want back tags that were manually related.
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* @see tag_get_related_tags()
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*/
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define('TAG_RELATED_MANUAL', 1);
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/**
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* Used to specify that we only want back tags where the relationship was automatically correlated.
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* @see tag_get_related_tags()
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*/
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define('TAG_RELATED_CORRELATED', 2);
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///////////////////////////////////////////////////////
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/////////////////// PUBLIC TAG API ////////////////////
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/// Functions for settings tags //////////////////////
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/**
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* Set the tags assigned to a record. This overwrites the current tags.
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*
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* This function is meant to be fed the string coming up from the user interface, which contains all tags assigned to a record.
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param string $record_type the type of record to tag ('post' for blogs, 'user' for users, 'tag' for tags, etc.)
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* @param int $record_id the id of the record to tag
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* @param array $tags the array of tags to set on the record. If given an empty array, all tags will be removed.
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* @param string|null $component the component that was tagged
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* @param int|null $contextid the context id of where this tag was assigned
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* @return bool|null
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*/
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function tag_set($record_type, $record_id, $tags, $component = null, $contextid = null) {
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static $in_recursion_semaphore = false; // this is to prevent loops when tagging a tag
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if ( $record_type == 'tag' && !$in_recursion_semaphore) {
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$current_tagged_tag_name = tag_get_name($record_id);
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}
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$tags_ids = tag_get_id($tags, TAG_RETURN_ARRAY); // force an array, even if we only have one tag.
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$cleaned_tags = tag_normalize($tags);
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//echo 'tags-in-tag_set'; var_dump($tags); var_dump($tags_ids); var_dump($cleaned_tags);
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$current_ids = tag_get_tags_ids($record_type, $record_id);
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//var_dump($current_ids);
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// for data coherence reasons, it's better to remove deleted tags
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// before adding new data: ordering could be duplicated.
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foreach($current_ids as $current_id) {
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if (!in_array($current_id, $tags_ids)) {
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tag_delete_instance($record_type, $record_id, $current_id);
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if ( $record_type == 'tag' && !$in_recursion_semaphore) {
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// if we are removing a tag-on-a-tag (manually related tag),
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// we need to remove the opposite relationship as well.
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tag_delete_instance('tag', $current_id, $record_id);
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}
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}
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}
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if (empty($tags)) {
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return true;
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}
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foreach($tags as $ordering => $tag) {
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$tag = trim($tag);
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if (!$tag) {
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continue;
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}
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$clean_tag = $cleaned_tags[$tag];
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$tag_current_id = $tags_ids[$clean_tag];
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if ( is_null($tag_current_id) ) {
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// create new tags
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//echo "call to add tag $tag\n";
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$new_tag = tag_add($tag);
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$tag_current_id = $new_tag[$clean_tag];
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}
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tag_assign($record_type, $record_id, $tag_current_id, $ordering, 0, $component, $contextid);
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// if we are tagging a tag (adding a manually-assigned related tag), we
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// need to create the opposite relationship as well.
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if ( $record_type == 'tag' && !$in_recursion_semaphore) {
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$in_recursion_semaphore = true;
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tag_set_add('tag', $tag_current_id, $current_tagged_tag_name, $component, $contextid);
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$in_recursion_semaphore = false;
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}
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}
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}
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/**
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* Adds a tag to a record, without overwriting the current tags.
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param string $record_type the type of record to tag ('post' for blogs, 'user' for users, etc.)
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* @param int $record_id the id of the record to tag
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* @param string $tag the tag to add
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* @param string|null $component the component that was tagged
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* @param int|null $contextid the context id of where this tag was assigned
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* @return bool|null
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*/
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function tag_set_add($record_type, $record_id, $tag, $component = null, $contextid = null) {
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$new_tags = array();
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foreach( tag_get_tags($record_type, $record_id) as $current_tag ) {
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$new_tags[] = $current_tag->rawname;
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}
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$new_tags[] = $tag;
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return tag_set($record_type, $record_id, $new_tags, $component, $contextid);
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}
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/**
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* Removes a tag from a record, without overwriting other current tags.
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param string $record_type the type of record to tag ('post' for blogs, 'user' for users, etc.)
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* @param int $record_id the id of the record to tag
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* @param string $tag the tag to delete
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* @param string|null $component the component that was tagged
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* @param int|null $contextid the context id of where this tag was assigned
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* @return bool|null
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*/
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function tag_set_delete($record_type, $record_id, $tag, $component = null, $contextid = null) {
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$new_tags = array();
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foreach( tag_get_tags($record_type, $record_id) as $current_tag ) {
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if ($current_tag->name != $tag) { // Keep all tags but the one specified
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$new_tags[] = $current_tag->name;
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}
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}
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return tag_set($record_type, $record_id, $new_tags, $component, $contextid);
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}
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/**
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* Set the type of a tag. At this time (version 2.2) the possible values are 'default' or 'official'. Official tags will be
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* displayed separately "at tagging time" (while selecting the tags to apply to a record).
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param string $tagid tagid to modify
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* @param string $type either 'default' or 'official'
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* @return bool true on success, false otherwise
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*/
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function tag_type_set($tagid, $type) {
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global $DB;
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if ($tag = $DB->get_record('tag', array('id' => $tagid), 'id, userid, name, rawname')) {
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$tag->tagtype = $type;
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$tag->timemodified = time();
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$DB->update_record('tag', $tag);
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$event = \core\event\tag_updated::create(array(
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'objectid' => $tag->id,
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'relateduserid' => $tag->userid,
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'context' => context_system::instance(),
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'other' => array(
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'name' => $tag->name,
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'rawname' => $tag->rawname
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)
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));
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$event->trigger();
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return true;
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}
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return false;
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}
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/**
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* Set the description of a tag
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param int $tagid the id of the tag
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* @param string $description the tag's description string to be set
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* @param int $descriptionformat the moodle text format of the description
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* {@link http://docs.moodle.org/dev/Text_formats_2.0#Database_structure}
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* @return bool true on success, false otherwise
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*/
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function tag_description_set($tagid, $description, $descriptionformat) {
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global $DB;
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if ($tag = $DB->get_record('tag', array('id' => $tagid), 'id, userid, name, rawname')) {
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$tag->description = $description;
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$tag->descriptionformat = $descriptionformat;
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$tag->timemodified = time();
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$DB->update_record('tag', $tag);
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$event = \core\event\tag_updated::create(array(
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'objectid' => $tag->id,
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'relateduserid' => $tag->userid,
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'context' => context_system::instance(),
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'other' => array(
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'name' => $tag->name,
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'rawname' => $tag->rawname
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)
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));
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$event->trigger();
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return true;
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}
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return false;
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}
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/// Functions for getting information about tags //////
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/**
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* Simple function to just return a single tag object when you know the name or something
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param string $field which field do we use to identify the tag: id, name or rawname
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* @param string $value the required value of the aforementioned field
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* @param string $returnfields which fields do we want returned. This is a comma seperated string containing any combination of
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* 'id', 'name', 'rawname' or '*' to include all fields.
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* @return mixed tag object
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*/
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function tag_get($field, $value, $returnfields='id, name, rawname') {
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global $DB;
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if ($field == 'name') {
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$value = core_text::strtolower($value); // To cope with input that might just be wrong case
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}
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return $DB->get_record('tag', array($field=>$value), $returnfields);
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}
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/**
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* Get the array of db record of tags associated to a record (instances). Use {@see tag_get_tags_csv()} if you wish to get the same
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* data in a comma-separated string, for instances such as needing to simply display a list of tags to the end user. This should
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* really be called tag_get_tag_instances().
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param string $record_type the record type for which we want to get the tags
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* @param int $record_id the record id for which we want to get the tags
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* @param string $type the tag type (either 'default' or 'official'). By default, all tags are returned.
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* @param int $userid (optional) only required for course tagging
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* @return array the array of tags
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*/
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function tag_get_tags($record_type, $record_id, $type=null, $userid=0) {
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global $CFG, $DB;
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$params = array();
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if ($type) {
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$sql_type = "AND tg.tagtype = :type";
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$params['type'] = $type;
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} else {
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$sql_type = '';
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}
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$u = null;
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if ($userid) {
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$u = "AND ti.tiuserid = :userid ";
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$params['userid'] = $userid;
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}
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$sql = "SELECT ti.id AS taginstanceid, tg.id, tg.tagtype, tg.name, tg.rawname, tg.flag, ti.ordering
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FROM {tag_instance} ti
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JOIN {tag} tg ON tg.id = ti.tagid
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WHERE ti.itemtype = :recordtype AND ti.itemid = :recordid $u $sql_type
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ORDER BY ti.ordering ASC";
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$params['recordtype'] = $record_type;
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$params['recordid'] = $record_id;
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// if the fields in this query are changed, you need to do the same changes in tag_get_correlated_tags
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return $DB->get_records_sql($sql, $params);
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// This version of the query, reversing the ON clause, "correctly" returns
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// a row with NULL values for instances that are still in the DB even though
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// the tag has been deleted. This shouldn't happen, but if it did, using
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// this query could help "clean it up". This causes bugs at this time.
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//$tags = $DB->get_records_sql("SELECT ti.tagid, tg.tagtype, tg.name, tg.rawname, tg.flag, ti.ordering ".
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// "FROM {tag_instance} ti LEFT JOIN {tag} tg ON ti.tagid = tg.id ".
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// "WHERE ti.itemtype = '{$record_type}' AND ti.itemid = '{$record_id}' {$type} ".
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// "ORDER BY ti.ordering ASC");
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}
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/**
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* Get the array of tags display names, indexed by id.
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param string $record_type the record type for which we want to get the tags
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* @param int $record_id the record id for which we want to get the tags
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* @param string $type the tag type (either 'default' or 'official'). By default, all tags are returned.
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* @return array the array of tags (with the value returned by tag_display_name), indexed by id
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*/
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function tag_get_tags_array($record_type, $record_id, $type=null) {
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$tags = array();
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foreach(tag_get_tags($record_type, $record_id, $type) as $tag) {
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$tags[$tag->id] = tag_display_name($tag);
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}
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return $tags;
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}
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/**
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* Get a comma-separated string of tags associated to a record. Use {@see tag_get_tags()} to get the same information in an array.
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*
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* @package core_tag
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* @category tag
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* @access public
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* @param string $record_type the record type for which we want to get the tags
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* @param int $record_id the record id for which we want to get the tags
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* @param int $html either TAG_RETURN_HTML or TAG_RETURN_TEXT, depending on the type of output desired
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* @param string $type either 'official' or 'default', if null, all tags are returned
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* @return string the comma-separated list of tags.
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*/
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function tag_get_tags_csv($record_type, $record_id, $html=TAG_RETURN_HTML, $type=null) {
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global $CFG;
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$tags_names = array();
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foreach(tag_get_tags($record_type, $record_id, $type) as $tag) {
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if ($html == TAG_RETURN_TEXT) {
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$tags_names[] = tag_display_name($tag, TAG_RETURN_TEXT);
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} else { // TAG_RETURN_HTML
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$tags_names[] = '<a href="'. $CFG->wwwroot .'/tag/index.php?tag='. rawurlencode($tag->name) .'">'. tag_display_name($tag) .'</a>';
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}
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}
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return implode(', ', $tags_names);
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}
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/**
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* Get an array of tag ids associated to a record.
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*
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* @package core_tag
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* @category tag
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* @access public
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* @todo MDL-31150 Update ordering property
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* @param string $record_type the record type for which we want to get the tags
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* @param int $record_id the record id for which we want to get the tags
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* @return array tag ids, indexed and sorted by 'ordering'
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*/
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function tag_get_tags_ids($record_type, $record_id) {
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$tag_ids = array();
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foreach (tag_get_tags($record_type, $record_id) as $tag) {
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if ( array_key_exists($tag->ordering, $tag_ids) ) {
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// until we can add a unique constraint, in table tag_instance,
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// on (itemtype, itemid, ordering), this is needed to prevent a bug
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// TODO MDL-31150 modify database in 2.0
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$tag->ordering++;
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}
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$tag_ids[$tag->ordering] = $tag->id;
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}
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ksort($tag_ids);
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return $tag_ids;
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}
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/**
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* Returns the database ID of a set of tags.
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*
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* @package core_tag
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* @category tag
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* @access public
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* @todo MDL-31152 Test the commented MDL-31152 todo in this function to see if it helps performance
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* without breaking anything.
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* @param mixed $tags one tag, or array of tags, to look for.
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* @param bool $return_value specify the type of the returned value. Either TAG_RETURN_OBJECT, or TAG_RETURN_ARRAY (default).
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* If TAG_RETURN_ARRAY is specified, an array will be returned even if only one tag was passed in $tags.
|
|
* @return mixed tag-indexed array of ids (or objects, if second parameter is TAG_RETURN_OBJECT), or only an int, if only one tag
|
|
* is given *and* the second parameter is null. No value for a key means the tag wasn't found.
|
|
*/
|
|
function tag_get_id($tags, $return_value=null) {
|
|
global $CFG, $DB;
|
|
|
|
static $tag_id_cache = array();
|
|
|
|
$return_an_int = false;
|
|
if (!is_array($tags)) {
|
|
if(is_null($return_value) || $return_value == TAG_RETURN_OBJECT) {
|
|
$return_an_int = true;
|
|
}
|
|
$tags = array($tags);
|
|
}
|
|
|
|
$result = array();
|
|
|
|
//TODO MDL-31152 test this and see if it helps performance without breaking anything
|
|
//foreach($tags as $key => $tag) {
|
|
// $clean_tag = core_text::strtolower($tag);
|
|
// if ( array_key_exists($clean_tag), $tag_id_cache) ) {
|
|
// $result[$clean_tag] = $tag_id_cache[$clean_tag];
|
|
// $tags[$key] = ''; // prevent further processing for this one.
|
|
// }
|
|
//}
|
|
|
|
$tags = array_values(tag_normalize($tags));
|
|
foreach($tags as $key => $tag) {
|
|
$tags[$key] = core_text::strtolower($tag);
|
|
$result[core_text::strtolower($tag)] = null; // key must exists : no value for a key means the tag wasn't found.
|
|
}
|
|
|
|
if (empty($tags)) {
|
|
return array();
|
|
}
|
|
|
|
list($tag_string, $params) = $DB->get_in_or_equal($tags);
|
|
|
|
$rs = $DB->get_recordset_sql("SELECT * FROM {tag} WHERE name $tag_string ORDER BY name", $params);
|
|
foreach ($rs as $record) {
|
|
if ($return_value == TAG_RETURN_OBJECT) {
|
|
$result[$record->name] = $record;
|
|
} else { // TAG_RETURN_ARRAY
|
|
$result[$record->name] = $record->id;
|
|
}
|
|
}
|
|
$rs->close();
|
|
|
|
if ($return_an_int) {
|
|
return array_pop($result);
|
|
}
|
|
|
|
return $result;
|
|
}
|
|
|
|
|
|
/**
|
|
* Returns tags related to a tag
|
|
*
|
|
* Related tags of a tag come from two sources:
|
|
* - manually added related tags, which are tag_instance entries for that tag
|
|
* - correlated tags, which are calculated
|
|
*
|
|
* @package core_tag
|
|
* @category tag
|
|
* @access public
|
|
* @param string $tagid is a single **normalized** tag name or the id of a tag
|
|
* @param int $type the function will return either manually (TAG_RELATED_MANUAL) related tags or correlated
|
|
* (TAG_RELATED_CORRELATED) tags. Default is TAG_RELATED_ALL, which returns everything.
|
|
* @param int $limitnum (optional) return a subset comprising this many records, the default is 10
|
|
* @return array an array of tag objects
|
|
*/
|
|
function tag_get_related_tags($tagid, $type=TAG_RELATED_ALL, $limitnum=10) {
|
|
|
|
$related_tags = array();
|
|
|
|
if ( $type == TAG_RELATED_ALL || $type == TAG_RELATED_MANUAL) {
|
|
//gets the manually added related tags
|
|
$related_tags = tag_get_tags('tag', $tagid);
|
|
}
|
|
|
|
if ( $type == TAG_RELATED_ALL || $type == TAG_RELATED_CORRELATED ) {
|
|
//gets the correlated tags
|
|
$automatic_related_tags = tag_get_correlated($tagid);
|
|
$related_tags = array_merge($related_tags, $automatic_related_tags);
|
|
}
|
|
|
|
// Remove duplicated tags (multiple instances of the same tag).
|
|
$seen = array();
|
|
foreach ($related_tags as $instance => $tag) {
|
|
if (isset($seen[$tag->id])) {
|
|
unset($related_tags[$instance]);
|
|
} else {
|
|
$seen[$tag->id] = 1;
|
|
}
|
|
}
|
|
|
|
return array_slice($related_tags, 0 , $limitnum);
|
|
}
|
|
|
|
/**
|
|
* Get a comma-separated list of tags related to another tag.
|
|
*
|
|
* @package core_tag
|
|
* @category tag
|
|
* @access public
|
|
* @param array $related_tags the array returned by tag_get_related_tags
|
|
* @param int $html either TAG_RETURN_HTML (default) or TAG_RETURN_TEXT : return html links, or just text.
|
|
* @return string comma-separated list
|
|
*/
|
|
function tag_get_related_tags_csv($related_tags, $html=TAG_RETURN_HTML) {
|
|
global $CFG;
|
|
|
|
$tags_names = array();
|
|
foreach($related_tags as $tag) {
|
|
if ( $html == TAG_RETURN_TEXT) {
|
|
$tags_names[] = tag_display_name($tag, TAG_RETURN_TEXT);
|
|
} else {
|
|
// TAG_RETURN_HTML
|
|
$tags_names[] = '<a href="'. $CFG->wwwroot .'/tag/index.php?tag='. rawurlencode($tag->name) .'">'. tag_display_name($tag) .'</a>';
|
|
}
|
|
}
|
|
|
|
return implode(', ', $tags_names);
|
|
}
|
|
|
|
/**
|
|
* Change the "value" of a tag, and update the associated 'name'.
|
|
*
|
|
* @package core_tag
|
|
* @category tag
|
|
* @access public
|
|
* @param int $tagid the id of the tag to modify
|
|
* @param string $newrawname the new rawname
|
|
* @return bool true on success, false otherwise
|
|
*/
|
|
function tag_rename($tagid, $newrawname) {
|
|
global $COURSE, $DB;
|
|
|
|
$norm = tag_normalize($newrawname, TAG_CASE_ORIGINAL);
|
|
if (! $newrawname_clean = array_shift($norm) ) {
|
|
return false;
|
|
}
|
|
|
|
if (! $newname_clean = core_text::strtolower($newrawname_clean)) {
|
|
return false;
|
|
}
|
|
|
|
// Prevent the rename if a tag with that name already exists
|
|
if ($existing = tag_get('name', $newname_clean, 'id, name, rawname')) {
|
|
if ($existing->id != $tagid) { // Another tag already exists with this name
|
|
return false;
|
|
}
|
|
}
|
|
|
|
if ($tag = tag_get('id', $tagid, 'id, userid, name, rawname')) {
|
|
// Store the name before we change it.
|
|
$oldname = $tag->name;
|
|
|
|
$tag->rawname = $newrawname_clean;
|
|
$tag->name = $newname_clean;
|
|
$tag->timemodified = time();
|
|
$DB->update_record('tag', $tag);
|
|
|
|
$event = \core\event\tag_updated::create(array(
|
|
'objectid' => $tag->id,
|
|
'relateduserid' => $tag->userid,
|
|
'context' => context_system::instance(),
|
|
'other' => array(
|
|
'name' => $newname_clean,
|
|
'rawname' => $newrawname_clean
|
|
)
|
|
));
|
|
$event->set_legacy_logdata(array($COURSE->id, 'tag', 'update', 'index.php?id='. $tag->id, $oldname . '->'. $tag->name));
|
|
$event->trigger();
|
|
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
|
|
/**
|
|
* Delete one or more tag, and all their instances if there are any left.
|
|
*
|
|
* @package core_tag
|
|
* @category tag
|
|
* @access public
|
|
* @param mixed $tagids one tagid (int), or one array of tagids to delete
|
|
* @return bool true on success, false otherwise
|
|
*/
|
|
function tag_delete($tagids) {
|
|
global $DB;
|
|
|
|
if (!is_array($tagids)) {
|
|
$tagids = array($tagids);
|
|
}
|
|
|
|
// Use the tagids to create a select statement to be used later.
|
|
list($tagsql, $tagparams) = $DB->get_in_or_equal($tagids);
|
|
|
|
// Store the tags and tag instances we are going to delete.
|
|
$tags = $DB->get_records_select('tag', 'id ' . $tagsql, $tagparams);
|
|
$taginstances = $DB->get_records_select('tag_instance', 'tagid ' . $tagsql, $tagparams);
|
|
|
|
// Delete all the tag instances.
|
|
$select = 'WHERE tagid ' . $tagsql;
|
|
$sql = "DELETE FROM {tag_instance} $select";
|
|
$DB->execute($sql, $tagparams);
|
|
|
|
// Delete all the tag correlations.
|
|
$sql = "DELETE FROM {tag_correlation} $select";
|
|
$DB->execute($sql, $tagparams);
|
|
|
|
// Delete all the tags.
|
|
$select = 'WHERE id ' . $tagsql;
|
|
$sql = "DELETE FROM {tag} $select";
|
|
$DB->execute($sql, $tagparams);
|
|
|
|
// Fire an event that these items were untagged.
|
|
if ($taginstances) {
|
|
// Save the system context in case the 'contextid' column in the 'tag_instance' table is null.
|
|
$syscontextid = context_system::instance()->id;
|
|
// Loop through the tag instances and fire a 'tag_removed'' event.
|
|
foreach ($taginstances as $taginstance) {
|
|
// We can not fire an event with 'null' as the contextid.
|
|
if (is_null($taginstance->contextid)) {
|
|
$taginstance->contextid = $syscontextid;
|
|
}
|
|
|
|
// Trigger tag removed event.
|
|
$event = \core\event\tag_removed::create(array(
|
|
'objectid' => $taginstance->id,
|
|
'contextid' => $taginstance->contextid,
|
|
'other' => array(
|
|
'tagid' => $taginstance->tagid,
|
|
'tagname' => $tags[$taginstance->tagid]->name,
|
|
'tagrawname' => $tags[$taginstance->tagid]->rawname,
|
|
'itemid' => $taginstance->itemid,
|
|
'itemtype' => $taginstance->itemtype
|
|
)
|
|
));
|
|
$event->add_record_snapshot('tag_instance', $taginstance);
|
|
$event->trigger();
|
|
}
|
|
}
|
|
|
|
// Fire an event that these tags were deleted.
|
|
if ($tags) {
|
|
$context = context_system::instance();
|
|
foreach ($tags as $tag) {
|
|
// Delete all files associated with this tag
|
|
$fs = get_file_storage();
|
|
$files = $fs->get_area_files($context->id, 'tag', 'description', $tag->id);
|
|
foreach ($files as $file) {
|
|
$file->delete();
|
|
}
|
|
|
|
// Trigger an event for deleting this tag.
|
|
$event = \core\event\tag_deleted::create(array(
|
|
'objectid' => $tag->id,
|
|
'relateduserid' => $tag->userid,
|
|
'context' => $context,
|
|
'other' => array(
|
|
'name' => $tag->name,
|
|
'rawname' => $tag->rawname
|
|
)
|
|
));
|
|
$event->add_record_snapshot('tag', $tag);
|
|
$event->trigger();
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Deletes all the tag instances given a component and an optional contextid.
|
|
*
|
|
* @param string $component
|
|
* @param int $contextid if null, then we delete all tag instances for the $component
|
|
*/
|
|
function tag_delete_instances($component, $contextid = null) {
|
|
global $DB;
|
|
|
|
$sql = "SELECT ti.*, t.name, t.rawname
|
|
FROM {tag_instance} ti
|
|
JOIN {tag} t
|
|
ON ti.tagid = t.id ";
|
|
if (is_null($contextid)) {
|
|
$params = array('component' => $component);
|
|
$sql .= "WHERE ti.component = :component";
|
|
} else {
|
|
$params = array('component' => $component, 'contextid' => $contextid);
|
|
$sql .= "WHERE ti.component = :component
|
|
AND ti.contextid = :contextid";
|
|
}
|
|
if ($taginstances = $DB->get_records_sql($sql, $params)) {
|
|
// Now remove all the tag instances.
|
|
$DB->delete_records('tag_instance',$params);
|
|
// Save the system context in case the 'contextid' column in the 'tag_instance' table is null.
|
|
$syscontextid = context_system::instance()->id;
|
|
// Loop through the tag instances and fire an 'tag_removed' event.
|
|
foreach ($taginstances as $taginstance) {
|
|
// We can not fire an event with 'null' as the contextid.
|
|
if (is_null($taginstance->contextid)) {
|
|
$taginstance->contextid = $syscontextid;
|
|
}
|
|
|
|
// Trigger tag removed event.
|
|
$event = \core\event\tag_removed::create(array(
|
|
'objectid' => $taginstance->id,
|
|
'contextid' => $taginstance->contextid,
|
|
'other' => array(
|
|
'tagid' => $taginstance->tagid,
|
|
'tagname' => $taginstance->name,
|
|
'tagrawname' => $taginstance->rawname,
|
|
'itemid' => $taginstance->itemid,
|
|
'itemtype' => $taginstance->itemtype
|
|
)
|
|
));
|
|
$event->add_record_snapshot('tag_instance', $taginstance);
|
|
$event->trigger();
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Delete one instance of a tag. If the last instance was deleted, it will also delete the tag, unless its type is 'official'.
|
|
*
|
|
* @package core_tag
|
|
* @category tag
|
|
* @access public
|
|
* @param string $record_type the type of the record for which to remove the instance
|
|
* @param int $record_id the id of the record for which to remove the instance
|
|
* @param int $tagid the tagid that needs to be removed
|
|
* @param int $userid (optional) the userid
|
|
* @return bool true on success, false otherwise
|
|
*/
|
|
function tag_delete_instance($record_type, $record_id, $tagid, $userid = null) {
|
|
global $DB;
|
|
|
|
if (is_null($userid)) {
|
|
$taginstance = $DB->get_record('tag_instance', array('tagid' => $tagid, 'itemtype' => $record_type, 'itemid' => $record_id));
|
|
} else {
|
|
$taginstance = $DB->get_record('tag_instance', array('tagid' => $tagid, 'itemtype' => $record_type, 'itemid' => $record_id,
|
|
'tiuserid' => $userid));
|
|
}
|
|
if ($taginstance) {
|
|
// Get the tag.
|
|
$tag = $DB->get_record('tag', array('id' => $tagid));
|
|
|
|
$DB->delete_records('tag_instance', array('id' => $taginstance->id));
|
|
|
|
// We can not fire an event with 'null' as the contextid.
|
|
if (is_null($taginstance->contextid)) {
|
|
$taginstance->contextid = context_system::instance()->id;
|
|
}
|
|
|
|
// Trigger tag removed event.
|
|
$event = \core\event\tag_removed::create(array(
|
|
'objectid' => $taginstance->id,
|
|
'contextid' => $taginstance->contextid,
|
|
'other' => array(
|
|
'tagid' => $tag->id,
|
|
'tagname' => $tag->name,
|
|
'tagrawname' => $tag->rawname,
|
|
'itemid' => $taginstance->itemid,
|
|
'itemtype' => $taginstance->itemtype
|
|
)
|
|
));
|
|
$event->add_record_snapshot('tag_instance', $taginstance);
|
|
$event->trigger();
|
|
|
|
// If there are no other instances of the tag then consider deleting the tag as well.
|
|
if (!$DB->record_exists('tag_instance', array('tagid' => $tagid))) {
|
|
// If the tag is a personal tag then delete it - don't delete official tags.
|
|
if ($tag->tagtype == 'default') {
|
|
tag_delete($tagid);
|
|
}
|
|
}
|
|
} else {
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
/**
|
|
* Function that returns the name that should be displayed for a specific tag
|
|
*
|
|
* @package core_tag
|
|
* @category tag
|
|
* @access public
|
|
* @param object $tagobject a line out of tag table, as returned by the adobd functions
|
|
* @param int $html TAG_RETURN_HTML (default) will return htmlspecialchars encoded string, TAG_RETURN_TEXT will not encode.
|
|
* @return string
|
|
*/
|
|
function tag_display_name($tagobject, $html=TAG_RETURN_HTML) {
|
|
global $CFG;
|
|
|
|
if (!isset($tagobject->name)) {
|
|
return '';
|
|
}
|
|
|
|
if (empty($CFG->keeptagnamecase)) {
|
|
//this is the normalized tag name
|
|
$tagname = core_text::strtotitle($tagobject->name);
|
|
} else {
|
|
//original casing of the tag name
|
|
$tagname = $tagobject->rawname;
|
|
}
|
|
|
|
// clean up a bit just in case the rules change again
|
|
$tagname = clean_param($tagname, PARAM_TAG);
|
|
|
|
if ($html == TAG_RETURN_TEXT) {
|
|
return $tagname;
|
|
} else { // TAG_RETURN_HTML
|
|
return htmlspecialchars($tagname);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Find all records tagged with a tag of a given type ('post', 'user', etc.)
|
|
*
|
|
* @package core_tag
|
|
* @category tag
|
|
* @access public
|
|
* @param string $tag tag to look for
|
|
* @param string $type type to restrict search to. If null, every matching record will be returned
|
|
* @param int $limitfrom (optional, required if $limitnum is set) return a subset of records, starting at this point.
|
|
* @param int $limitnum (optional, required if $limitfrom is set) return a subset comprising this many records.
|
|
* @return array of matching objects, indexed by record id, from the table containing the type requested
|
|
*/
|
|
function tag_find_records($tag, $type, $limitfrom='', $limitnum='') {
|
|
global $CFG, $DB;
|
|
|
|
if (!$tag || !$type) {
|
|
return array();
|
|
}
|
|
|
|
$tagid = tag_get_id($tag);
|
|
|
|
$query = "SELECT it.*
|
|
FROM {".$type."} it INNER JOIN {tag_instance} tt ON it.id = tt.itemid
|
|
WHERE tt.itemtype = ? AND tt.tagid = ?";
|
|
$params = array($type, $tagid);
|
|
|
|
return $DB->get_records_sql($query, $params, $limitfrom, $limitnum);
|
|
}
|
|
|
|
|
|
|
|
|
|
///////////////////////////////////////////////////////
|
|
/////////////////// PRIVATE TAG API ///////////////////
|
|
|
|
/**
|
|
* Adds one or more tag in the database. This function should not be called directly : you should
|
|
* use tag_set.
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param mixed $tags one tag, or an array of tags, to be created
|
|
* @param string $type type of tag to be created ("default" is the default value and "official" is the only other supported
|
|
* value at this time). An official tag is kept even if there are no records tagged with it.
|
|
* @return array $tags ids indexed by their lowercase normalized names. Any boolean false in the array indicates an error while
|
|
* adding the tag.
|
|
*/
|
|
function tag_add($tags, $type="default") {
|
|
global $USER, $DB;
|
|
|
|
if (!is_array($tags)) {
|
|
$tags = array($tags);
|
|
}
|
|
|
|
$tag_object = new StdClass;
|
|
$tag_object->tagtype = $type;
|
|
$tag_object->userid = $USER->id;
|
|
$tag_object->timemodified = time();
|
|
|
|
$clean_tags = tag_normalize($tags, TAG_CASE_ORIGINAL);
|
|
|
|
$tags_ids = array();
|
|
foreach($clean_tags as $tag) {
|
|
$tag = trim($tag);
|
|
if (!$tag) {
|
|
$tags_ids[$tag] = false;
|
|
} else {
|
|
// note that the difference between rawname and name is only
|
|
// capitalization : the rawname is NOT the same at the rawtag.
|
|
$tag_object->rawname = $tag;
|
|
$tag_name_lc = core_text::strtolower($tag);
|
|
$tag_object->name = $tag_name_lc;
|
|
//var_dump($tag_object);
|
|
$tags_ids[$tag_name_lc] = $DB->insert_record('tag', $tag_object);
|
|
|
|
$event = \core\event\tag_created::create(array(
|
|
'objectid' => $tags_ids[$tag_name_lc],
|
|
'relateduserid' => $tag_object->userid,
|
|
'context' => context_system::instance(),
|
|
'other' => array(
|
|
'name' => $tag_object->name,
|
|
'rawname' => $tag_object->rawname
|
|
)
|
|
));
|
|
$event->trigger();
|
|
}
|
|
}
|
|
|
|
return $tags_ids;
|
|
}
|
|
|
|
/**
|
|
* Assigns a tag to a record; if the record already exists, the time and ordering will be updated.
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param string $record_type the type of the record that will be tagged
|
|
* @param int $record_id the id of the record that will be tagged
|
|
* @param string $tagid the tag id to set on the record.
|
|
* @param int $ordering the order of the instance for this record
|
|
* @param int $userid (optional) only required for course tagging
|
|
* @param string|null $component the component that was tagged
|
|
* @param int|null $contextid the context id of where this tag was assigned
|
|
* @return bool true on success, false otherwise
|
|
*/
|
|
function tag_assign($record_type, $record_id, $tagid, $ordering, $userid = 0, $component = null, $contextid = null) {
|
|
global $DB;
|
|
|
|
if ($component === null || $contextid === null) {
|
|
debugging('You should specify the component and contextid of the item being tagged in your call to tag_assign.',
|
|
DEBUG_DEVELOPER);
|
|
}
|
|
|
|
// Get the tag.
|
|
$tag = $DB->get_record('tag', array('id' => $tagid), 'name, rawname', MUST_EXIST);
|
|
|
|
if ( $tag_instance_object = $DB->get_record('tag_instance', array('tagid'=>$tagid, 'itemtype'=>$record_type, 'itemid'=>$record_id, 'tiuserid'=>$userid), 'id')) {
|
|
$tag_instance_object->ordering = $ordering;
|
|
$tag_instance_object->timemodified = time();
|
|
|
|
$DB->update_record('tag_instance', $tag_instance_object);
|
|
} else {
|
|
$tag_instance_object = new StdClass;
|
|
$tag_instance_object->tagid = $tagid;
|
|
$tag_instance_object->component = $component;
|
|
$tag_instance_object->itemid = $record_id;
|
|
$tag_instance_object->itemtype = $record_type;
|
|
$tag_instance_object->contextid = $contextid;
|
|
$tag_instance_object->ordering = $ordering;
|
|
$tag_instance_object->timecreated = time();
|
|
$tag_instance_object->timemodified = $tag_instance_object->timecreated;
|
|
$tag_instance_object->tiuserid = $userid;
|
|
|
|
$tag_instance_object->id = $DB->insert_record('tag_instance', $tag_instance_object);
|
|
}
|
|
|
|
// We can not fire an event with 'null' as the contextid.
|
|
if (is_null($contextid)) {
|
|
$contextid = context_system::instance()->id;
|
|
}
|
|
|
|
// Trigger tag added event.
|
|
$event = \core\event\tag_added::create(array(
|
|
'objectid' => $tag_instance_object->id,
|
|
'contextid' => $contextid,
|
|
'other' => array(
|
|
'tagid' => $tagid,
|
|
'tagname' => $tag->name,
|
|
'tagrawname' => $tag->rawname,
|
|
'itemid' => $record_id,
|
|
'itemtype' => $record_type
|
|
)
|
|
));
|
|
$event->trigger();
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Function that returns tags that start with some text, for use by the autocomplete feature
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param string $text string that the tag names will be matched against
|
|
* @return mixed an array of objects, or false if no records were found or an error occured.
|
|
*/
|
|
function tag_autocomplete($text) {
|
|
global $DB;
|
|
return $DB->get_records_sql("SELECT tg.id, tg.name, tg.rawname
|
|
FROM {tag} tg
|
|
WHERE tg.name LIKE ?", array(core_text::strtolower($text)."%"));
|
|
}
|
|
|
|
/**
|
|
* Clean up the tag tables, making sure all tagged object still exists.
|
|
*
|
|
* This should normally not be necessary, but in case related tags are not deleted when the tagged record is removed, this should be
|
|
* done once in a while, perhaps on an occasional cron run. On a site with lots of tags, this could become an expensive function to
|
|
* call: don't run at peak time.
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @todo MDL-31212 Update tag cleanup sql so that it supports multiple types of tags
|
|
*/
|
|
function tag_cleanup() {
|
|
global $DB;
|
|
|
|
// Get ids to delete from instances where the tag has been deleted. This should never happen apparently.
|
|
$sql = "SELECT ti.id
|
|
FROM {tag_instance} ti
|
|
LEFT JOIN {tag} t ON t.id = ti.tagid
|
|
WHERE t.id IS null";
|
|
$tagids = $DB->get_records_sql($sql);
|
|
$tagarray = array();
|
|
foreach ($tagids as $tagid) {
|
|
$tagarray[] = $tagid->id;
|
|
}
|
|
|
|
// Next get ids from instances that have an owner that has been deleted.
|
|
$sql = "SELECT ti.id
|
|
FROM {tag_instance} ti, {user} u
|
|
WHERE ti.itemid = u.id
|
|
AND ti.itemtype = 'user'
|
|
AND u.deleted = 1";
|
|
$tagids = $DB->get_records_sql($sql);
|
|
foreach ($tagids as $tagid) {
|
|
$tagarray[] = $tagid->id;
|
|
}
|
|
|
|
// Get the other itemtypes.
|
|
$sql = "SELECT itemtype
|
|
FROM {tag_instance}
|
|
WHERE itemtype <> 'user'
|
|
GROUP BY itemtype";
|
|
$tagitemtypes = $DB->get_records_sql($sql);
|
|
foreach ($tagitemtypes as $key => $notused) {
|
|
$sql = 'SELECT ti.id
|
|
FROM {tag_instance} ti
|
|
LEFT JOIN {' . $key . '} it ON it.id = ti.itemid
|
|
WHERE it.id IS null
|
|
AND ti.itemtype = \'' . $key . '\'';
|
|
$tagids = $DB->get_records_sql($sql);
|
|
foreach ($tagids as $tagid) {
|
|
$tagarray[] = $tagid->id;
|
|
}
|
|
}
|
|
|
|
// Get instances for each of the ids to be deleted.
|
|
if (count($tagarray) > 0) {
|
|
list($sqlin, $params) = $DB->get_in_or_equal($tagarray);
|
|
$sql = "SELECT ti.*, COALESCE(t.name, 'deleted') AS name, COALESCE(t.rawname, 'deleted') AS rawname
|
|
FROM {tag_instance} ti
|
|
LEFT JOIN {tag} t ON t.id = ti.tagid
|
|
WHERE ti.id $sqlin";
|
|
$instances = $DB->get_records_sql($sql, $params);
|
|
tag_bulk_delete_instances($instances);
|
|
}
|
|
|
|
// TODO MDL-31212 this will only clean tags of type 'default'. This is good as
|
|
// it won't delete 'official' tags, but the day we get more than two
|
|
// types, we need to fix this.
|
|
$unused_tags = $DB->get_recordset_sql("SELECT tg.id
|
|
FROM {tag} tg
|
|
WHERE tg.tagtype = 'default'
|
|
AND NOT EXISTS (
|
|
SELECT 'x'
|
|
FROM {tag_instance} ti
|
|
WHERE ti.tagid = tg.id
|
|
)");
|
|
|
|
// cleanup tags
|
|
foreach ($unused_tags as $unused_tag) {
|
|
tag_delete($unused_tag->id);
|
|
//debugging('deleting unused tag #'. $unused_tag->id, DEBUG_DEVELOPER);
|
|
}
|
|
$unused_tags->close();
|
|
}
|
|
|
|
/**
|
|
* This function will delete numerous tag instances efficiently.
|
|
* This removes tag instances only. It doesn't check to see if it is the last use of a tag.
|
|
*
|
|
* @param array $instances An array of tag instance objects with the addition of the tagname and tagrawname
|
|
* (used for recording a delete event).
|
|
*/
|
|
function tag_bulk_delete_instances($instances) {
|
|
global $DB;
|
|
|
|
$instanceids = array();
|
|
foreach ($instances as $instance) {
|
|
$instanceids[] = $instance->id;
|
|
}
|
|
|
|
// This is a multi db compatible method of creating the correct sql when using the 'IN' value.
|
|
// $insql is the sql statement, $params are the id numbers.
|
|
list($insql, $params) = $DB->get_in_or_equal($instanceids);
|
|
$sql = 'id ' . $insql;
|
|
$DB->delete_records_select('tag_instance', $sql, $params);
|
|
|
|
// Now go through and record each tag individually with the event system.
|
|
foreach ($instances as $instance) {
|
|
// Trigger tag removed event (i.e. The tag instance has been removed).
|
|
$event = \core\event\tag_removed::create(array(
|
|
'objectid' => $instance->id,
|
|
'contextid' => $instance->contextid,
|
|
'other' => array(
|
|
'tagid' => $instance->tagid,
|
|
'tagname' => $instance->name,
|
|
'tagrawname' => $instance->rawname,
|
|
'itemid' => $instance->itemid,
|
|
'itemtype' => $instance->itemtype
|
|
)
|
|
));
|
|
unset($instance->name);
|
|
unset($instance->rawname);
|
|
$event->add_record_snapshot('tag_instance', $instance);
|
|
$event->trigger();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Calculates and stores the correlated tags of all tags. The correlations are stored in the 'tag_correlation' table.
|
|
*
|
|
* Two tags are correlated if they appear together a lot. Ex.: Users tagged with "computers" will probably also be tagged with "algorithms".
|
|
*
|
|
* The rationale for the 'tag_correlation' table is performance. It works as a cache for a potentially heavy load query done at the
|
|
* 'tag_instance' table. So, the 'tag_correlation' table stores redundant information derived from the 'tag_instance' table.
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param int $mincorrelation Only tags with more than $mincorrelation correlations will be identified.
|
|
*/
|
|
function tag_compute_correlations($mincorrelation = 2) {
|
|
global $DB;
|
|
|
|
// This mighty one line query fetches a row from the database for every
|
|
// individual tag correlation. We then need to process the rows collecting
|
|
// the correlations for each tag id.
|
|
// The fields used by this query are as follows:
|
|
// tagid : This is the tag id, there should be at least $mincorrelation
|
|
// rows for each tag id.
|
|
// correlation : This is the tag id that correlates to the above tagid field.
|
|
// correlationid : This is the id of the row in the tag_correlation table that
|
|
// relates to the tagid field and will be NULL if there are no
|
|
// existing correlations
|
|
$sql = 'SELECT pairs.tagid, pairs.correlation, pairs.ocurrences, co.id AS correlationid
|
|
FROM (
|
|
SELECT ta.tagid, tb.tagid AS correlation, COUNT(*) AS ocurrences
|
|
FROM {tag_instance} ta
|
|
JOIN {tag_instance} tb ON (ta.itemtype = tb.itemtype AND ta.itemid = tb.itemid AND ta.tagid <> tb.tagid)
|
|
GROUP BY ta.tagid, tb.tagid
|
|
HAVING COUNT(*) > :mincorrelation
|
|
) pairs
|
|
LEFT JOIN {tag_correlation} co ON co.tagid = pairs.tagid
|
|
ORDER BY pairs.tagid ASC, pairs.ocurrences DESC, pairs.correlation ASC';
|
|
$rs = $DB->get_recordset_sql($sql, array('mincorrelation' => $mincorrelation));
|
|
|
|
// Set up an empty tag correlation object
|
|
$tagcorrelation = new stdClass;
|
|
$tagcorrelation->id = null;
|
|
$tagcorrelation->tagid = null;
|
|
$tagcorrelation->correlatedtags = array();
|
|
|
|
// We store each correlation id in this array so we can remove any correlations
|
|
// that no longer exist.
|
|
$correlations = array();
|
|
|
|
// Iterate each row of the result set and build them into tag correlations.
|
|
// We add all of a tag's correlations to $tagcorrelation->correlatedtags[]
|
|
// then save the $tagcorrelation object
|
|
foreach ($rs as $row) {
|
|
if ($row->tagid != $tagcorrelation->tagid) {
|
|
// The tag id has changed so we have all of the correlations for this tag
|
|
$tagcorrelationid = tag_process_computed_correlation($tagcorrelation);
|
|
if ($tagcorrelationid) {
|
|
$correlations[] = $tagcorrelationid;
|
|
}
|
|
// Now we reset the tag correlation object so we can reuse it and set it
|
|
// up for the current record.
|
|
$tagcorrelation = new stdClass;
|
|
$tagcorrelation->id = $row->correlationid;
|
|
$tagcorrelation->tagid = $row->tagid;
|
|
$tagcorrelation->correlatedtags = array();
|
|
}
|
|
//Save the correlation on the tag correlation object
|
|
$tagcorrelation->correlatedtags[] = $row->correlation;
|
|
}
|
|
// Update the current correlation after the last record.
|
|
$tagcorrelationid = tag_process_computed_correlation($tagcorrelation);
|
|
if ($tagcorrelationid) {
|
|
$correlations[] = $tagcorrelationid;
|
|
}
|
|
|
|
|
|
// Close the recordset
|
|
$rs->close();
|
|
|
|
// Remove any correlations that weren't just identified
|
|
if (empty($correlations)) {
|
|
//there are no tag correlations
|
|
$DB->delete_records('tag_correlation');
|
|
} else {
|
|
list($sql, $params) = $DB->get_in_or_equal($correlations, SQL_PARAMS_NAMED, 'param0000', false);
|
|
$DB->delete_records_select('tag_correlation', 'id '.$sql, $params);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* This function processes a tag correlation and makes changes in the database as required.
|
|
*
|
|
* The tag correlation object needs have both a tagid property and a correlatedtags property that is an array.
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param stdClass $tagcorrelation
|
|
* @return int/bool The id of the tag correlation that was just processed or false.
|
|
*/
|
|
function tag_process_computed_correlation(stdClass $tagcorrelation) {
|
|
global $DB;
|
|
|
|
// You must provide a tagid and correlatedtags must be set and be an array
|
|
if (empty($tagcorrelation->tagid) || !isset($tagcorrelation->correlatedtags) || !is_array($tagcorrelation->correlatedtags)) {
|
|
return false;
|
|
}
|
|
|
|
$tagcorrelation->correlatedtags = join(',', $tagcorrelation->correlatedtags);
|
|
if (!empty($tagcorrelation->id)) {
|
|
// The tag correlation already exists so update it
|
|
$DB->update_record('tag_correlation', $tagcorrelation);
|
|
} else {
|
|
// This is a new correlation to insert
|
|
$tagcorrelation->id = $DB->insert_record('tag_correlation', $tagcorrelation);
|
|
}
|
|
return $tagcorrelation->id;
|
|
}
|
|
|
|
/**
|
|
* Tasks that should be performed at cron time
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
*/
|
|
function tag_cron() {
|
|
tag_compute_correlations();
|
|
tag_cleanup();
|
|
}
|
|
|
|
/**
|
|
* Search for tags with names that match some text
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param string $text escaped string that the tag names will be matched against
|
|
* @param bool $ordered If true, tags are ordered by their popularity. If false, no ordering.
|
|
* @param int/string $limitfrom (optional, required if $limitnum is set) return a subset of records, starting at this point.
|
|
* @param int/string $limitnum (optional, required if $limitfrom is set) return a subset comprising this many records.
|
|
* @return array/boolean an array of objects, or false if no records were found or an error occured.
|
|
*/
|
|
function tag_find_tags($text, $ordered=true, $limitfrom='', $limitnum='') {
|
|
global $DB;
|
|
|
|
$norm = tag_normalize($text, TAG_CASE_LOWER);
|
|
$text = array_shift($norm);
|
|
|
|
if ($ordered) {
|
|
$query = "SELECT tg.id, tg.name, tg.rawname, COUNT(ti.id) AS count
|
|
FROM {tag} tg LEFT JOIN {tag_instance} ti ON tg.id = ti.tagid
|
|
WHERE tg.name LIKE ?
|
|
GROUP BY tg.id, tg.name, tg.rawname
|
|
ORDER BY count DESC";
|
|
} else {
|
|
$query = "SELECT tg.id, tg.name, tg.rawname
|
|
FROM {tag} tg
|
|
WHERE tg.name LIKE ?";
|
|
}
|
|
$params = array("%{$text}%");
|
|
return $DB->get_records_sql($query, $params, $limitfrom , $limitnum);
|
|
}
|
|
|
|
/**
|
|
* Get the name of a tag
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param mixed $tagids the id of the tag, or an array of ids
|
|
* @return mixed string name of one tag, or id-indexed array of strings
|
|
*/
|
|
function tag_get_name($tagids) {
|
|
global $DB;
|
|
|
|
if (!is_array($tagids)) {
|
|
if ($tag = $DB->get_record('tag', array('id'=>$tagids))) {
|
|
return $tag->name;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
$tag_names = array();
|
|
foreach($DB->get_records_list('tag', 'id', $tagids) as $tag) {
|
|
$tag_names[$tag->id] = $tag->name;
|
|
}
|
|
|
|
return $tag_names;
|
|
}
|
|
|
|
/**
|
|
* Returns the correlated tags of a tag, retrieved from the tag_correlation table. Make sure cron runs, otherwise the table will be
|
|
* empty and this function won't return anything.
|
|
*
|
|
* Correlated tags are calculated in cron based on existing tag instances.
|
|
*
|
|
* This function will return as many entries as there are existing tag instances,
|
|
* which means that there will be duplicates for each tag.
|
|
*
|
|
* If you need only one record for each correlated tag please call:
|
|
* tag_get_related_tags($tag_id, TAG_RELATED_CORRELATED);
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param int $tag_id is a single tag id
|
|
* @param int $notused this argument is no longer used
|
|
* @return array an array of tag objects or an empty if no correlated tags are found
|
|
*/
|
|
function tag_get_correlated($tag_id, $notused = null) {
|
|
global $DB;
|
|
|
|
$tag_correlation = $DB->get_record('tag_correlation', array('tagid'=>$tag_id));
|
|
|
|
if (!$tag_correlation || empty($tag_correlation->correlatedtags)) {
|
|
return array();
|
|
}
|
|
|
|
// this is (and has to) return the same fields as the query in tag_get_tags
|
|
$sql = "SELECT ti.id AS taginstanceid, tg.id, tg.tagtype, tg.name, tg.rawname, tg.flag, ti.ordering
|
|
FROM {tag} tg
|
|
INNER JOIN {tag_instance} ti ON tg.id = ti.tagid
|
|
WHERE tg.id IN ({$tag_correlation->correlatedtags})
|
|
ORDER BY ti.ordering ASC";
|
|
return $DB->get_records_sql($sql);
|
|
}
|
|
|
|
/**
|
|
* Function that normalizes a list of tag names.
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param array/string $rawtags array of tags, or a single tag.
|
|
* @param int $case case to use for returned value (default: lower case). Either TAG_CASE_LOWER (default) or TAG_CASE_ORIGINAL
|
|
* @return array lowercased normalized tags, indexed by the normalized tag, in the same order as the original array.
|
|
* (Eg: 'Banana' => 'banana').
|
|
*/
|
|
function tag_normalize($rawtags, $case = TAG_CASE_LOWER) {
|
|
|
|
// cache normalized tags, to prevent costly repeated calls to clean_param
|
|
static $cleaned_tags_lc = array(); // lower case - use for comparison
|
|
static $cleaned_tags_mc = array(); // mixed case - use for saving to database
|
|
|
|
if ( !is_array($rawtags) ) {
|
|
$rawtags = array($rawtags);
|
|
}
|
|
|
|
$result = array();
|
|
foreach($rawtags as $rawtag) {
|
|
$rawtag = trim($rawtag);
|
|
if (!$rawtag) {
|
|
continue;
|
|
}
|
|
if ( !array_key_exists($rawtag, $cleaned_tags_lc) ) {
|
|
$cleaned_tags_lc[$rawtag] = core_text::strtolower( clean_param($rawtag, PARAM_TAG) );
|
|
$cleaned_tags_mc[$rawtag] = clean_param($rawtag, PARAM_TAG);
|
|
}
|
|
if ( $case == TAG_CASE_LOWER ) {
|
|
$result[$rawtag] = $cleaned_tags_lc[$rawtag];
|
|
} else { // TAG_CASE_ORIGINAL
|
|
$result[$rawtag] = $cleaned_tags_mc[$rawtag];
|
|
}
|
|
}
|
|
|
|
return $result;
|
|
}
|
|
|
|
/**
|
|
* Count how many records are tagged with a specific tag.
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param string $record_type record to look for ('post', 'user', etc.)
|
|
* @param int $tagid is a single tag id
|
|
* @return int number of mathing tags.
|
|
*/
|
|
function tag_record_count($record_type, $tagid) {
|
|
global $DB;
|
|
return $DB->count_records('tag_instance', array('itemtype'=>$record_type, 'tagid'=>$tagid));
|
|
}
|
|
|
|
/**
|
|
* Determine if a record is tagged with a specific tag
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param string $record_type the record type to look for
|
|
* @param int $record_id the record id to look for
|
|
* @param string $tag a tag name
|
|
* @return bool/int true if it is tagged, 0 (false) otherwise
|
|
*/
|
|
function tag_record_tagged_with($record_type, $record_id, $tag) {
|
|
global $DB;
|
|
if ($tagid = tag_get_id($tag)) {
|
|
return $DB->count_records('tag_instance', array('itemtype'=>$record_type, 'itemid'=>$record_id, 'tagid'=>$tagid));
|
|
} else {
|
|
return 0; // tag doesn't exist
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Flag a tag as inappropriate.
|
|
*
|
|
* @param int|array $tagids a single tagid, or an array of tagids
|
|
*/
|
|
function tag_set_flag($tagids) {
|
|
global $DB;
|
|
|
|
$tagids = (array) $tagids;
|
|
|
|
// Use the tagids to create a select statement to be used later.
|
|
list($tagsql, $tagparams) = $DB->get_in_or_equal($tagids, SQL_PARAMS_NAMED);
|
|
|
|
// Update all the tags to flagged.
|
|
$sql = "UPDATE {tag}
|
|
SET flag = flag + 1, timemodified = :time
|
|
WHERE id $tagsql";
|
|
|
|
// Update all the tags.
|
|
$DB->execute($sql, array_merge(array('time' => time()), $tagparams));
|
|
|
|
// Get all the tags.
|
|
if ($tags = $DB->get_records_select('tag', 'id '. $tagsql, $tagparams, 'id ASC')) {
|
|
// Loop through and fire an event for each tag that it was flagged.
|
|
foreach ($tags as $tag) {
|
|
$event = \core\event\tag_flagged::create(array(
|
|
'objectid' => $tag->id,
|
|
'relateduserid' => $tag->userid,
|
|
'context' => context_system::instance(),
|
|
'other' => array(
|
|
'name' => $tag->name,
|
|
'rawname' => $tag->rawname
|
|
)
|
|
|
|
));
|
|
$event->add_record_snapshot('tag', $tag);
|
|
$event->trigger();
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Remove the inappropriate flag on a tag.
|
|
*
|
|
* @param int|array $tagids a single tagid, or an array of tagids
|
|
*/
|
|
function tag_unset_flag($tagids) {
|
|
global $DB;
|
|
|
|
$tagids = (array) $tagids;
|
|
|
|
// Use the tagids to create a select statement to be used later.
|
|
list($tagsql, $tagparams) = $DB->get_in_or_equal($tagids, SQL_PARAMS_NAMED);
|
|
|
|
// Update all the tags to unflagged.
|
|
$sql = "UPDATE {tag}
|
|
SET flag = 0, timemodified = :time
|
|
WHERE id $tagsql";
|
|
|
|
// Update all the tags.
|
|
$DB->execute($sql, array_merge(array('time' => time()), $tagparams));
|
|
|
|
// Get all the tags.
|
|
if ($tags = $DB->get_records_select('tag', 'id '. $tagsql, $tagparams, 'id ASC')) {
|
|
// Loop through and fire an event for each tag that it was unflagged.
|
|
foreach ($tags as $tag) {
|
|
$event = \core\event\tag_unflagged::create(array(
|
|
'objectid' => $tag->id,
|
|
'relateduserid' => $tag->userid,
|
|
'context' => context_system::instance(),
|
|
'other' => array(
|
|
'name' => $tag->name,
|
|
'rawname' => $tag->rawname
|
|
)
|
|
));
|
|
$event->add_record_snapshot('tag', $tag);
|
|
$event->trigger();
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Return a list of page types
|
|
*
|
|
* @package core_tag
|
|
* @access private
|
|
* @param string $pagetype current page type
|
|
* @param stdClass $parentcontext Block's parent context
|
|
* @param stdClass $currentcontext Current context of block
|
|
*/
|
|
function tag_page_type_list($pagetype, $parentcontext, $currentcontext) {
|
|
return array(
|
|
'tag-*'=>get_string('page-tag-x', 'tag'),
|
|
'tag-index'=>get_string('page-tag-index', 'tag'),
|
|
'tag-search'=>get_string('page-tag-search', 'tag'),
|
|
'tag-manage'=>get_string('page-tag-manage', 'tag')
|
|
);
|
|
}
|