Moodle APIs 3.9
Moodle 3.9.13+ (Build: 20220325)
Public Member Functions | Static Protected Member Functions | Static Protected Attributes | List of all members
core_availability\tree_node Class Reference

Node (base class) used to construct a tree of availability conditions. More...

Inheritance diagram for core_availability\tree_node:
core_availability\condition core_availability\tree availability_completion\condition availability_date\condition availability_grade\condition availability_group\condition availability_grouping\condition availability_profile\condition

Public Member Functions

 check_available ($not, core_availability\info $info, $grabthelot, $userid)
 Determines whether this particular item is currently available according to the availability criteria. More...
 
 filter_user_list (array $users, $not, core_availability\info $info, capability_checker $checker)
 Tests this condition against a user list. More...
 
 get_user_list_sql ($not, core_availability\info $info, $onlyactive)
 Obtains SQL that returns a list of enrolled users that has been filtered by the conditions applied in the availability API, similar to calling get_enrolled_users and then filter_user_list. More...
 
 include_after_restore ($restoreid, $courseid, base_logger $logger, $name, base_task $task)
 Checks whether this node should be included after restore or not. More...
 
 is_applied_to_user_lists ()
 Checks whether this condition applies to user lists. More...
 
 is_available_for_all ($not=false)
 Checks whether this condition is actually going to be available for all users under normal circumstances. More...
 
 save ()
 Saves tree data back to a structure object. More...
 
 update_after_restore ($restoreid, $courseid, base_logger $logger, $name)
 Updates this node after restore, returning true if anything changed. More...
 
 update_dependency_id ($table, $oldid, $newid)
 Updates this node if it contains any references (dependencies) to the given table and id. More...
 

Static Protected Member Functions

static unique_sql_parameter (array &$params, $value)
 Utility function for generating SQL parameters (because we can't use ? parameters because get_enrolled_sql has infected us with horrible named parameters). More...
 

Static Protected Attributes

static int $uniquesqlparametercounter = 1
 Counter to be used in tree_node::unique_sql_parameter().
 

Detailed Description

Node (base class) used to construct a tree of availability conditions.

License
http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

Member Function Documentation

◆ check_available()

core_availability\tree_node::check_available (   $not,
core_availability\info  $info,
  $grabthelot,
  $userid 
)
abstract

Determines whether this particular item is currently available according to the availability criteria.

  • This does not include the 'visible' setting (i.e. this might return true even if visible is false); visible is handled independently.
  • This does not take account of the viewhiddenactivities capability. That should apply later.

The $not option is potentially confusing. This option always indicates the 'real' value of NOT. For example, a condition inside a 'NOT AND' group will get this called with $not = true, but if you put another 'NOT OR' group inside the first group, then a condition inside that will be called with $not = false. We need to use the real values, rather than the more natural use of the current value at this point inside the tree, so that the information displayed to users makes sense.

Parameters
bool$notSet true if we are inverting the condition
core_availability::info$infoItem we're checking
bool$grabthelotPerformance hint: if true, caches information required for all course-modules, to make the front page and similar pages work more quickly (works only for current user)
int$useridUser ID to check availability for
Return values
resultAvailability check result

◆ filter_user_list()

core_availability\tree_node::filter_user_list ( array  $users,
  $not,
core_availability\info  $info,
capability_checker  $checker 
)

Tests this condition against a user list.

Users who do not meet the condition will be removed from the list, unless they have the ability to view hidden activities/sections.

This function must be implemented if is_applied_to_user_lists returns true. Otherwise it will not be called.

The function must operate efficiently, e.g. by using a fixed number of database queries regardless of how many users are in the list.

Within this function, if you need to check capabilities, please use the provided checker which caches results where possible.

Conditions do not need to check the viewhiddenactivities or viewhiddensections capabilities. These are handled by core_availability::info::filter_user_list.

Parameters
array$usersArray of userid => object
bool$notTrue if this condition is applying in negative mode
core_availability::info$infoItem we're checking
capability_checker$checker
Return values
arrayFiltered version of input array
Exceptions
coding_exceptionIf called on a condition that doesn't apply to user lists

◆ get_user_list_sql()

core_availability\tree_node::get_user_list_sql (   $not,
core_availability\info  $info,
  $onlyactive 
)

Obtains SQL that returns a list of enrolled users that has been filtered by the conditions applied in the availability API, similar to calling get_enrolled_users and then filter_user_list.

As for filter_user_list, this ONLY filters out users with conditions that are marked as applying to user lists. For example, group conditions are included but date conditions are not included.

The returned SQL is a query that returns a list of user IDs. It does not include brackets, so you neeed to add these to make it into a subquery. You would normally use it in an SQL phrase like "WHERE u.id IN ($sql)".

The SQL will be complex and may be slow. It uses named parameters (sorry, I know they are annoying, but it was unavoidable here).

If there are no conditions, the returned result is array('', array()).

Conditions do not need to check the viewhiddenactivities or viewhiddensections capabilities. These are handled by core_availability::info::get_user_list_sql.

Parameters
bool$notTrue if this condition is applying in negative mode
core_availability::info$infoItem we're checking
bool$onlyactiveIf true, only returns active enrolments
Return values
arrayArray with two elements: SQL subquery and parameters array
Exceptions
coding_exceptionIf called on a condition that doesn't apply to user lists

◆ include_after_restore()

core_availability\tree_node::include_after_restore (   $restoreid,
  $courseid,
base_logger  $logger,
  $name,
base_task  $task 
)

Checks whether this node should be included after restore or not.

The node may be removed depending on restore settings, which you can get from the $task object.

By default nodes are still included after restore.

Parameters
string$restoreidRestore ID
int$courseidID of target course
base_logger$loggerLogger for any warnings
string$nameName of this item (for use in warning messages)
base_task$taskCurrent restore task
Return values
boolTrue if there was any change

Reimplemented in availability_group\condition, and availability_grouping\condition.

◆ is_applied_to_user_lists()

core_availability\tree_node::is_applied_to_user_lists ( )

Checks whether this condition applies to user lists.

The default is false (the condition is used to control access, but does not prevent the student from appearing in lists).

For example, group conditions apply to user lists: we do not want to include a student in a list of users if they are prohibited from accessing the activity because they don't belong to a relevant group. However, date conditions do not apply - we still want to show users in a list of people who might have submitted an assignment, even if they are no longer able to access the assignment in question because there is a date restriction.

The general idea is that conditions which are likely to be permanent (group membership, user profile) apply to user lists. Conditions which are likely to be temporary (date, grade requirement) do not.

Conditions which do apply to user lists must implement the filter_user_list function.

Return values
boolTrue if this condition applies to user lists

Reimplemented in core_availability\tree, availability_group\condition, availability_grouping\condition, and availability_profile\condition.

◆ is_available_for_all()

core_availability\tree_node::is_available_for_all (   $not = false)
abstract

Checks whether this condition is actually going to be available for all users under normal circumstances.

Normally, if there are any conditions, then it may be hidden. However in the case of date conditions there are some conditions which will definitely not result in it being hidden for anyone.

Parameters
bool$notSet true if we are inverting the condition
Return values
boolTrue if condition will return available for everyone

Reimplemented in core_availability\condition, core_availability\tree, and availability_date\condition.

◆ save()

core_availability\tree_node::save ( )
abstract

Saves tree data back to a structure object.

Return values
stdClassStructure object (ready to be made into JSON format)

Reimplemented in core_availability\tree, availability_completion\condition, availability_date\condition, availability_grade\condition, availability_group\condition, availability_grouping\condition, and availability_profile\condition.

◆ unique_sql_parameter()

static core_availability\tree_node::unique_sql_parameter ( array &  $params,
  $value 
)
staticprotected

Utility function for generating SQL parameters (because we can't use ? parameters because get_enrolled_sql has infected us with horrible named parameters).

Parameters
array$paramsParams array (value will be added to this array)
string | int$valueValue
Return values
SQLcode for the parameter, e.g. ':pr1234'

◆ update_after_restore()

core_availability\tree_node::update_after_restore (   $restoreid,
  $courseid,
base_logger  $logger,
  $name 
)

Updates this node after restore, returning true if anything changed.

The default behaviour is simply to return false. If there is a problem with the update, $logger can be used to output a warning.

Note: If you need information about the date offset, call core_availability::info::get_restore_date_offset($restoreid). For information on the restoring task and its settings, call core_availability::info::get_restore_task($restoreid).

Parameters
string$restoreidRestore ID
int$courseidID of target course
base_logger$loggerLogger for any warnings
string$nameName of this item (for use in warning messages)
Return values
boolTrue if there was any change

Reimplemented in availability_date\condition, core_availability\tree, availability_completion\condition, availability_grade\condition, availability_group\condition, and availability_grouping\condition.

◆ update_dependency_id()

core_availability\tree_node::update_dependency_id (   $table,
  $oldid,
  $newid 
)
abstract

Updates this node if it contains any references (dependencies) to the given table and id.

Parameters
string$tableTable name e.g. 'course_modules'
int$oldidPrevious ID
int$newidNew ID
Return values
boolTrue if it changed, otherwise false

Reimplemented in core_availability\condition, core_availability\tree, availability_completion\condition, availability_grade\condition, availability_group\condition, and availability_grouping\condition.


The documentation for this class was generated from the following file: