Tag API before 3.1

Moodle 2.0

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Tag API overview

The Tag API has been implemented in lib/moodlelib.php.

examplefunction()

Example function description.

Tag API Usage

Example

$id = mt_rand(1000000000, 9999999999); // Generating a key that is unlikely to be taken

tag_set('foo_user', $id, array()); // Delete all foo_user->$id tags by passing an empty array tag_get_tags('foo_user', $id); // returns an empty array()

tag_set_add('foo_user', $id, 'chess'); // Add chess to the list of tags for foo_user->$id tag_get_tags('foo_user', $id); /* returns: Array (

   [14] => stdClass Object
       (
           [id] => 14
           [tagtype] => default
           [name] => chess
           [rawname] => chess
           [flag] => 0
           [ordering] => 0
       )

)

• /

tag_set_delete('foo_user', $id, 'chess'); //Delete the chess tag for foo_user->$id tag_get_tags('foo_user', $id); // returns an empty array()

br(""); tag_set('foo_user', $id, array('table tennis', 'foosball', 'programming')); //Add some more tags for foo_user->$id $tags = tag_get_tags('foo_user', $id); /* $tags = Array (

   [15] => stdClass Object
       (
           [id] => 15
           [tagtype] => official
           [name] => table tennis
           [rawname] => table tennis
           [flag] => 0
           [ordering] => 0
       )

   [16] => stdClass Object
       (
           [id] => 16
           [tagtype] => default
           [name] => foosball
           [rawname] => foosball
           [flag] => 0
           [ordering] => 1
       )

   [17] => stdClass Object
       (
           [id] => 17
           [tagtype] => default
           [name] => programming
           [rawname] => programming
           [flag] => 0
           [ordering] => 2
       )

)

• /

$firstTagKey = key($tags); // Grab the first key (which happens to be the key for table tennis). tag_type_set($firstTagKey, 'official'); // Make table tennis an official tag // output only official foo_user->$id tags tag_get_tags('foo_user', $id, 'official'); /* Returns: Array (

   [15] => stdClass Object
       (
           [id] => 15
           [tagtype] => official
           [name] => table tennis
           [rawname] => table tennis
           [flag] => 0
           [ordering] => 0
       )

)

• /

// Set a description for the table tennis tag.

tag_description_set($firstTagKey, '

Another name for wiff-waff"

', FORMAT_HTML);

// Output a tag cloud for all tags in the system. tag_print_cloud();

Tag API database tables

Tag

This table holds all of the tags which are currently available in the system.

Field	Type	Default	Info
id	int(10)	auto-incrementing	The unique ID for this Tag.
userid	int(10)		The user that the Tag belongs to
name	varchar(255)	null	The name of the tag
rawname	varchar(255)		A version of the name which has been normalised with functions such as clean_param and strtolower
tagtype	varchar(255) NULL	null	Specifies the type of the tag. Currently there are only two types of tags, official and default. Official is used for tags that have been accepted by administrators.
description	text NULL		A description of the tag. It's format is specified by the descriptionformat field of this table
descriptionformat	tinyint(2) unsigned	0	Specifies the MOODLE TEXT format of the description (see: https://docs.moodle.org/dev/Text_formats_2.0#Database_structure)
flag	smallint(4)	0	Used to identify tags that have been marked as inappropriate
timemodified	bigint(10)		The time that the tag was last updated.

Tag_Instance

This table is use to record the instances of each tag's use. It has a many to one relationship with the tag table shown above.

Field	Type	Default	Info
id	int(10)	auto-incrementing	The unique ID for this tag instance
tagid	int(10)		The foreign key which relates to the primary tagid key in the tag table
itemtype	varchar(255)	null	The category that the tag belongs to (eg. user, course)
itemid	int(10)		The ID of the particular item you are linking to. So for an itemtype of user you would use the user's ID for the itemid.
tiuserid	int(10)	0	The userid of the user who created the tag instance.
ordering	int(10)		See http://tracker.moodle.org/browse/MDL-31150
timemodified	int(10)	0	The time that the tag instace was last updated.