silverstripe-framework/model/DataList.php
Julian Seidenberg 10199f908a API Data corruption on Versioned due to lazy loading
Lazy loading no longer loads fields from the versions table when querying. This could lead to incorrect data being displayed if the data on the object and the version it pointed to did not match.

API methods to allow setting of the context of the query that generated the DataObject on that object (used by the lazy loading mechanism to correctly query the Stage, Live, or Versions tables)

See https://github.com/silverstripe/sapphire/pull/1178 for context.
2013-02-14 14:28:42 +01:00

1099 lines
29 KiB
PHP

<?php
/**
* Implements a "lazy loading" DataObjectSet.
* Uses {@link DataQuery} to do the actual query generation.
*
* DataLists are _immutable_ as far as the query they represent is concerned. When you call a method that
* alters the query, a new DataList instance is returned, rather than modifying the existing instance
*
* When you add or remove an element to the list the query remains the same, but because you have modified
* the underlying data the contents of the list changes. These are some of those methods:
*
* - add
* - addMany
* - remove
* - removeMany
* - removeByID
* - removeByFilter
* - removeAll
*
* Subclasses of DataList may add other methods that have the same effect.
*
* @package framework
* @subpackage model
*/
class DataList extends ViewableData implements SS_List, SS_Filterable, SS_Sortable, SS_Limitable {
/**
* The DataObject class name that this data list is querying
*
* @var string
*/
protected $dataClass;
/**
* The {@link DataQuery} object responsible for getting this DataList's records
*
* @var DataQuery
*/
protected $dataQuery;
/**
* The DataModel from which this DataList comes.
*
* @var DataModel
*/
protected $model;
/**
* Create a new DataList.
* No querying is done on construction, but the initial query schema is set up.
*
* @param string $dataClass - The DataObject class to query.
*/
public function __construct($dataClass) {
$this->dataClass = $dataClass;
$this->dataQuery = new DataQuery($this->dataClass);
parent::__construct();
}
/**
* Set the DataModel
*
* @param DataModel $model
*/
public function setDataModel(DataModel $model) {
$this->model = $model;
}
/**
* Get the dataClass name for this DataList, ie the DataObject ClassName
*
* @return string
*/
public function dataClass() {
return $this->dataClass;
}
/**
* When cloning this object, clone the dataQuery object as well
*/
public function __clone() {
$this->dataQuery = clone $this->dataQuery;
}
/**
* Return a copy of the internal {@link DataQuery} object
*
* Because the returned value is a copy, modifying it won't affect this list's contents. If
* you want to alter the data query directly, use the alterDataQuery method
*
* @return DataQuery
*/
public function dataQuery() {
return clone $this->dataQuery;
}
/**
* @var bool - Indicates if we are in an alterDataQueryCall already, so alterDataQuery can be re-entrant
*/
protected $inAlterDataQueryCall = false;
/**
* Return a new DataList instance with the underlying {@link DataQuery} object altered
*
* If you want to alter the underlying dataQuery for this list, this wrapper method
* will ensure that you can do so without mutating the existing List object.
*
* It clones this list, calls the passed callback function with the dataQuery of the new
* list as it's first parameter (and the list as it's second), then returns the list
*
* Note that this function is re-entrant - it's safe to call this inside a callback passed to
* alterDataQuery
*
* @param $callback
* @return DataList
*/
public function alterDataQuery($callback) {
if ($this->inAlterDataQueryCall) {
$list = $this;
$res = call_user_func($callback, $list->dataQuery, $list);
if ($res) $list->dataQuery = $res;
return $list;
}
else {
$list = clone $this;
$list->inAlterDataQueryCall = true;
try {
$res = call_user_func($callback, $list->dataQuery, $list);
if ($res) $list->dataQuery = $res;
}
catch (Exception $e) {
$list->inAlterDataQueryCall = false;
throw $e;
}
$list->inAlterDataQueryCall = false;
return $list;
}
}
/**
* Return a new DataList instance with the underlying {@link DataQuery} object changed
*
* @param DataQuery $dataQuery
* @return DataList
*/
public function setDataQuery(DataQuery $dataQuery) {
$clone = clone $this;
$clone->dataQuery = $dataQuery;
return $clone;
}
public function setDataQueryParam($keyOrArray, $val = null) {
$clone = clone $this;
if(is_array($keyOrArray)) {
foreach($keyOrArray as $key => $val) {
$clone->dataQuery->setQueryParam($key, $val);
}
}
else {
$clone->dataQuery->setQueryParam($keyOrArray, $val);
}
return $clone;
}
/**
* Returns the SQL query that will be used to get this DataList's records. Good for debugging. :-)
*
* @return SQLQuery
*/
public function sql() {
return $this->dataQuery->query()->sql();
}
/**
* Return a new DataList instance with a WHERE clause added to this list's query.
*
* @param string $filter Escaped SQL statement
* @return DataList
*/
public function where($filter) {
return $this->alterDataQuery(function($query) use ($filter){
$query->where($filter);
});
}
/**
* Returns true if this DataList can be sorted by the given field.
*
* @param string $fieldName
* @return boolean
*/
public function canSortBy($fieldName) {
return $this->dataQuery()->query()->canSortBy($fieldName);
}
/**
*
* @param string $fieldName
* @return boolean
*/
public function canFilterBy($fieldName) {
if($t = singleton($this->dataClass)->hasDatabaseField($fieldName)){
return true;
}
return false;
}
/**
* Return a new DataList instance with the records returned in this query restricted by a limit clause
*
* @param int $limit
* @param int $offset
*/
public function limit($limit, $offset = 0) {
if(!$limit && !$offset) {
return $this;
}
return $this->alterDataQuery(function($query) use ($limit, $offset){
$query->limit($limit, $offset);
});
}
/**
* Return a new DataList instance as a copy of this data list with the sort order set
*
* @see SS_List::sort()
* @see SQLQuery::orderby
* @example $list = $list->sort('Name'); // default ASC sorting
* @example $list = $list->sort('Name DESC'); // DESC sorting
* @example $list = $list->sort('Name', 'ASC');
* @example $list = $list->sort(array('Name'=>'ASC,'Age'=>'DESC'));
*
* @param String|array Escaped SQL statement. If passed as array, all keys and values are assumed to be escaped.
* @return DataList
*/
public function sort() {
$count = func_num_args();
if($count == 0) {
return $this;
}
if($count > 2) {
throw new InvalidArgumentException('This method takes zero, one or two arguments');
}
$sort = $col = $dir = null;
if ($count == 2) {
list($col, $dir) = func_get_args();
}
else {
$sort = func_get_arg(0);
}
return $this->alterDataQuery(function($query, $list) use ($sort, $col, $dir){
if ($col) {
// sort('Name','Desc')
if(!in_array(strtolower($dir),array('desc','asc'))){
user_error('Second argument to sort must be either ASC or DESC');
}
$query->sort($col, $dir);
}
else if(is_string($sort) && $sort){
// sort('Name ASC')
if(stristr($sort, ' asc') || stristr($sort, ' desc')) {
$query->sort($sort);
} else {
$query->sort($sort, 'ASC');
}
}
else if(is_array($sort)) {
// sort(array('Name'=>'desc'));
$query->sort(null, null); // wipe the sort
foreach($sort as $col => $dir) {
// Convert column expressions to SQL fragment, while still allowing the passing of raw SQL
// fragments.
try {
$relCol = $list->getRelationName($col);
} catch(InvalidArgumentException $e) {
$relCol = $col;
}
$query->sort($relCol, $dir, false);
}
}
});
}
/**
* Return a copy of this list which only includes items with these charactaristics
*
* @see SS_List::filter()
*
* @example $list = $list->filter('Name', 'bob'); // only bob in the list
* @example $list = $list->filter('Name', array('aziz', 'bob'); // aziz and bob in list
* @example $list = $list->filter(array('Name'=>'bob, 'Age'=>21)); // bob with the age 21
* @example $list = $list->filter(array('Name'=>'bob, 'Age'=>array(21, 43))); // bob with the Age 21 or 43
* @example $list = $list->filter(array('Name'=>array('aziz','bob'), 'Age'=>array(21, 43)));
* // aziz with the age 21 or 43 and bob with the Age 21 or 43
*
* @todo extract the sql from $customQuery into a SQLGenerator class
*
* @param string|array Escaped SQL statement. If passed as array, all keys and values are assumed to be escaped.
* @return DataList
*/
public function filter() {
// Validate and process arguments
$arguments = func_get_args();
switch(sizeof($arguments)) {
case 1: $filters = $arguments[0]; break;
case 2: $filters = array($arguments[0] => $arguments[1]); break;
default:
throw new InvalidArgumentException('Incorrect number of arguments passed to filter()');
}
return $this->addFilter($filters);
}
/**
* Return a new instance of the list with an added filter
*/
public function addFilter($filterArray) {
$list = $this;
foreach($filterArray as $field => $value) {
$fieldArgs = explode(':', $field);
$field = array_shift($fieldArgs);
$filterType = array_shift($fieldArgs);
$modifiers = $fieldArgs;
$list = $list->applyFilterContext($field, $filterType, $modifiers, $value);
}
return $list;
}
/**
* Return a copy of this list which does not contain items matching any of these charactaristics.
*
* @example // filter bob from list
* $list = $list->filterAny('Name', 'bob');
* // SQL: WHERE "Name" = 'bob'
* @example // filter aziz and bob from list
* $list = $list->filterAny('Name', array('aziz', 'bob');
* // SQL: WHERE ("Name" IN ('aziz','bob'))
* @example // filter by bob or anybody aged 21
* $list = $list->filterAny(array('Name'=>'bob, 'Age'=>21));
* // SQL: WHERE ("Name" = 'bob' OR "Age" = '21')
* @example // filter by bob or anybody aged 21 or 43
* $list = $list->filterAny(array('Name'=>'bob, 'Age'=>array(21, 43)));
* // SQL: WHERE ("Name" = 'bob' OR ("Age" IN ('21', '43'))
* @example // bob age 21 or 43, phil age 21 or 43 would be excluded
* $list = $list->filterAny(array('Name'=>array('bob','phil'), 'Age'=>array(21, 43)));
* // SQL: WHERE (("Name" IN ('bob', 'phil')) OR ("Age" IN ('21', '43'))
*
* @todo extract the sql from this method into a SQLGenerator class
*
* @param string|array See {@link filter()}
* @return DataList
*/
public function filterAny() {
$numberFuncArgs = count(func_get_args());
$whereArguments = array();
if($numberFuncArgs == 1 && is_array(func_get_arg(0))) {
$whereArguments = func_get_arg(0);
} elseif($numberFuncArgs == 2) {
$whereArguments[func_get_arg(0)] = func_get_arg(1);
} else {
throw new InvalidArgumentException('Incorrect number of arguments passed to exclude()');
}
return $this->alterDataQuery(function($query, $list) use ($whereArguments) {
$subquery = $query->disjunctiveGroup();
foreach($whereArguments as $field => $value) {
$fieldArgs = explode(':',$field);
$field = array_shift($fieldArgs);
$filterType = array_shift($fieldArgs);
$modifiers = $fieldArgs;
// This is here since PHP 5.3 can't call protected/private methods in a closure.
$t = singleton($list->dataClass())->dbObject($field);
if($filterType) {
$className = "{$filterType}Filter";
} else {
$className = 'ExactMatchFilter';
}
if(!class_exists($className)){
$className = 'ExactMatchFilter';
array_unshift($modifiers, $filterType);
}
$t = new $className($field, $value, $modifiers);
$t->apply($subquery);
}
});
}
/**
* Filter this DataList by a callback function.
* The function will be passed each record of the DataList in turn, and must return true for the record to be
* included. Returns the filtered list.
*
* Note that, in the current implementation, the filtered list will be an ArrayList, but this may change in a
* future implementation.
*/
public function filterByCallback($callback) {
if(!is_callable($callback)) {
throw new LogicException("DataList::filterByCallback() must be passed something callable.");
}
$output = new ArrayList;
foreach($this as $item) {
if($callback($item)) $output->push($item);
}
return $output;
}
/**
* Translates a Object relation name to a Database name and apply the relation join to
* the query. Throws an InvalidArgumentException if the $field doesn't correspond to a relation
*
* @param string $field
* @return string
*/
public function getRelationName($field) {
if(!preg_match('/^[A-Z0-9._]+$/i', $field)) {
throw new InvalidArgumentException("Bad field expression $field");
}
if (!$this->inAlterDataQueryCall) {
Deprecation::notice('3.1',
'getRelationName is mutating, and must be called inside an alterDataQuery block');
}
if(strpos($field,'.') === false) {
return '"'.$field.'"';
}
$relations = explode('.', $field);
$fieldName = array_pop($relations);
$relationModelName = $this->dataQuery->applyRelation($field);
return '"'.$relationModelName.'"."'.$fieldName.'"';
}
/**
* Translates a filter type to a SQL query.
*
* @param string $field - the fieldname in the db
* @param string $filter - example StartsWith, relates to a filtercontext
* @param array $modifiers - Modifiers to pass to the filter, ie not,nocase
* @param string $value - the value that the filtercontext will use for matching
* @todo Deprecated SearchContexts and pull their functionality into the core of the ORM
*/
private function applyFilterContext($field, $filter, $modifiers, $value) {
if($filter) {
$className = "{$filter}Filter";
} else {
$className = 'ExactMatchFilter';
}
if(!class_exists($className)) {
$className = 'ExactMatchFilter';
array_unshift($modifiers, $filter);
}
$t = new $className($field, $value, $modifiers);
return $this->alterDataQuery(array($t, 'apply'));
}
/**
* Return a copy of this list which does not contain any items with these charactaristics
*
* @see SS_List::exclude()
* @example $list = $list->exclude('Name', 'bob'); // exclude bob from list
* @example $list = $list->exclude('Name', array('aziz', 'bob'); // exclude aziz and bob from list
* @example $list = $list->exclude(array('Name'=>'bob, 'Age'=>21)); // exclude bob that has Age 21
* @example $list = $list->exclude(array('Name'=>'bob, 'Age'=>array(21, 43))); // exclude bob with Age 21 or 43
* @example $list = $list->exclude(array('Name'=>array('bob','phil'), 'Age'=>array(21, 43)));
* // bob age 21 or 43, phil age 21 or 43 would be excluded
*
* @todo extract the sql from this method into a SQLGenerator class
*
* @param string|array Escaped SQL statement. If passed as array, all keys and values are assumed to be escaped.
* @return DataList
*/
public function exclude() {
$numberFuncArgs = count(func_get_args());
$whereArguments = array();
if($numberFuncArgs == 1 && is_array(func_get_arg(0))) {
$whereArguments = func_get_arg(0);
} elseif($numberFuncArgs == 2) {
$whereArguments[func_get_arg(0)] = func_get_arg(1);
} else {
throw new InvalidArgumentException('Incorrect number of arguments passed to exclude()');
}
return $this->alterDataQuery(function($query, $list) use ($whereArguments) {
$subquery = $query->disjunctiveGroup();
foreach($whereArguments as $field => $value) {
$fieldArgs = explode(':', $field);
$field = array_shift($fieldArgs);
$filterType = array_shift($fieldArgs);
$modifiers = $fieldArgs;
// This is here since PHP 5.3 can't call protected/private methods in a closure.
$t = singleton($list->dataClass())->dbObject($field);
if($filterType) {
$className = "{$filterType}Filter";
} else {
$className = 'ExactMatchFilter';
}
if(!class_exists($className)){
$className = 'ExactMatchFilter';
array_unshift($modifiers, $filterType);
}
$t = new $className($field, $value, $modifiers);
$t->exclude($subquery);
}
});
}
/**
* This method returns a copy of this list that does not contain any DataObjects that exists in $list
*
* The $list passed needs to contain the same dataclass as $this
*
* @param SS_List $list
* @return DataList
* @throws BadMethodCallException
*/
public function subtract(SS_List $list) {
if($this->dataclass() != $list->dataclass()) {
throw new InvalidArgumentException('The list passed must have the same dataclass as this class');
}
return $this->alterDataQuery(function($query) use ($list){
$query->subtract($list->dataQuery());
});
}
/**
* Return a new DataList instance with an inner join clause added to this list's query.
*
* @param string $table Table name (unquoted and as escaped SQL)
* @param string $onClause Escaped SQL statement, e.g. '"Table1"."ID" = "Table2"."ID"'
* @param string $alias - if you want this table to be aliased under another name
* @return DataList
*/
public function innerJoin($table, $onClause, $alias = null) {
return $this->alterDataQuery(function($query) use ($table, $onClause, $alias){
$query->innerJoin($table, $onClause, $alias);
});
}
/**
* Return a new DataList instance with a left join clause added to this list's query.
*
* @param string $table Table name (unquoted and as escaped SQL)
* @param string $onClause Escaped SQL statement, e.g. '"Table1"."ID" = "Table2"."ID"'
* @param string $alias - if you want this table to be aliased under another name
* @return DataList
*/
public function leftJoin($table, $onClause, $alias = null) {
return $this->alterDataQuery(function($query) use ($table, $onClause, $alias){
$query->leftJoin($table, $onClause, $alias);
});
}
/**
* Return an array of the actual items that this DataList contains at this stage.
* This is when the query is actually executed.
*
* @return array
*/
public function toArray() {
$query = $this->dataQuery->query();
$rows = $query->execute();
$results = array();
foreach($rows as $row) {
$results[] = $this->createDataObject($row);
}
return $results;
}
/**
* Return this list as an array and every object it as an sub array as well
*
* @return type
*/
public function toNestedArray() {
$result = array();
foreach($this as $item) {
$result[] = $item->toMap();
}
return $result;
}
/**
* Walks the list using the specified callback
*
* @param callable $callback
* @return DataList
*/
public function each($callback) {
foreach($this as $row) {
$callback($row);
}
return $this;
}
public function debug() {
$val = "<h2>" . $this->class . "</h2><ul>";
foreach($this->toNestedArray() as $item) {
$val .= "<li style=\"list-style-type: disc; margin-left: 20px\">" . Debug::text($item) . "</li>";
}
$val .= "</ul>";
return $val;
}
/**
* Returns a map of this list
*
* @param string $keyField - the 'key' field of the result array
* @param string $titleField - the value field of the result array
* @return SS_Map
*/
public function map($keyField = 'ID', $titleField = 'Title') {
return new SS_Map($this, $keyField, $titleField);
}
/**
* Create a DataObject from the given SQL row
*
* @param array $row
* @return DataObject
*/
protected function createDataObject($row) {
$defaultClass = $this->dataClass;
// Failover from RecordClassName to ClassName
if(empty($row['RecordClassName'])) {
$row['RecordClassName'] = $row['ClassName'];
}
// Instantiate the class mentioned in RecordClassName only if it exists, otherwise default to $this->dataClass
if(class_exists($row['RecordClassName'])) {
$item = Injector::inst()->create($row['RecordClassName'], $row, false, $this->model);
} else {
$item = Injector::inst()->create($defaultClass, $row, false, $this->model);
}
//set query params on the DataObject to tell the lazy loading mechanism the context the object creation context
$item->setSourceQueryParams($this->dataQuery()->getQueryParams());
return $item;
}
/**
* Returns an Iterator for this DataList.
* This function allows you to use DataLists in foreach loops
*
* @return ArrayIterator
*/
public function getIterator() {
return new ArrayIterator($this->toArray());
}
/**
* Return the number of items in this DataList
*
* @return int
*/
public function count() {
return $this->dataQuery->count();
}
/**
* Return the maximum value of the given field in this DataList
*
* @param string $fieldName
* @return mixed
*/
public function max($fieldName) {
return $this->dataQuery->max($fieldName);
}
/**
* Return the minimum value of the given field in this DataList
*
* @param string $fieldName
* @return mixed
*/
public function min($fieldName) {
return $this->dataQuery->min($fieldName);
}
/**
* Return the average value of the given field in this DataList
*
* @param string $fieldName
* @return mixed
*/
public function avg($fieldName) {
return $this->dataQuery->avg($fieldName);
}
/**
* Return the sum of the values of the given field in this DataList
*
* @param string $fieldName
* @return mixed
*/
public function sum($fieldName) {
return $this->dataQuery->sum($fieldName);
}
/**
* Returns the first item in this DataList
*
* @return DataObject
*/
public function first() {
foreach($this->dataQuery->firstRow()->execute() as $row) {
return $this->createDataObject($row);
}
}
/**
* Returns the last item in this DataList
*
* @return DataObject
*/
public function last() {
foreach($this->dataQuery->lastRow()->execute() as $row) {
return $this->createDataObject($row);
}
}
/**
* Returns true if this DataList has items
*
* @return bool
*/
public function exists() {
return $this->count() > 0;
}
/**
* Get a sub-range of this dataobjectset as an array
*
* @param int $offset
* @param int $length
* @return DataList
*/
public function getRange($offset, $length) {
Deprecation::notice("3.0", 'Use limit($length, $offset) instead. Note the new argument order.');
return $this->limit($length, $offset);
}
/**
* Find the first DataObject of this DataList where the given key = value
*
* @param string $key
* @param string $value
* @return DataObject|null
*/
public function find($key, $value) {
if($key == 'ID') {
$baseClass = ClassInfo::baseDataClass($this->dataClass);
$SQL_col = sprintf('"%s"."%s"', $baseClass, Convert::raw2sql($key));
} else {
$SQL_col = sprintf('"%s"', Convert::raw2sql($key));
}
return $this->where("$SQL_col = '" . Convert::raw2sql($value) . "'")->First();
}
/**
* Restrict the columns to fetch into this DataList
*
* @param array $queriedColumns
* @return DataList
*/
public function setQueriedColumns($queriedColumns) {
return $this->alterDataQuery(function($query) use ($queriedColumns){
$query->setQueriedColumns($queriedColumns);
});
}
/**
* Filter this list to only contain the given Primary IDs
*
* @param array $ids Array of integers, will be automatically cast/escaped.
* @return DataList
*/
public function byIDs(array $ids) {
$ids = array_map('intval', $ids); // sanitize
$baseClass = ClassInfo::baseDataClass($this->dataClass);
return $this->where("\"$baseClass\".\"ID\" IN (" . implode(',', $ids) .")");
}
/**
* Return the first DataObject with the given ID
*
* @param int $id
* @return DataObject
*/
public function byID($id) {
$baseClass = ClassInfo::baseDataClass($this->dataClass);
return $this->where("\"$baseClass\".\"ID\" = " . (int)$id)->First();
}
/**
* Returns an array of a single field value for all items in the list.
*
* @param string $colName
* @return array
*/
public function column($colName = "ID") {
return $this->dataQuery->column($colName);
}
// Member altering methods
/**
* Sets the ComponentSet to be the given ID list.
* Records will be added and deleted as appropriate.
*
* @param array $idList List of IDs.
*/
public function setByIDList($idList) {
$has = array();
// Index current data
foreach($this->column() as $id) {
$has[$id] = true;
}
// Keep track of items to delete
$itemsToDelete = $has;
// add items in the list
// $id is the database ID of the record
if($idList) foreach($idList as $id) {
unset($itemsToDelete[$id]);
if($id && !isset($has[$id])) {
$this->add($id);
}
}
// Remove any items that haven't been mentioned
$this->removeMany(array_keys($itemsToDelete));
}
/**
* Returns an array with both the keys and values set to the IDs of the records in this list.
*
*/
public function getIDList() {
$ids = $this->column("ID");
return $ids ? array_combine($ids, $ids) : array();
}
/**
* Returns a HasManyList or ManyMany list representing the querying of a relation across all
* objects in this data list. For it to work, the relation must be defined on the data class
* that you used to create this DataList.
*
* Example: Get members from all Groups:
*
* DataList::Create("Group")->relation("Members")
*
* @param string $relationName
* @return HasManyList|ManyManyList
*/
public function relation($relationName) {
$ids = $this->column('ID');
return singleton($this->dataClass)->$relationName()->forForeignID($ids);
}
public function dbObject($fieldName) {
return singleton($this->dataClass)->dbObject($fieldName);
}
/**
* Add a number of items to the component set.
*
* @param array $items Items to add, as either DataObjects or IDs.
* @return DataList
*/
public function addMany($items) {
foreach($items as $item) {
$this->add($item);
}
return $this;
}
/**
* Remove the items from this list with the given IDs
*
* @param array $idList
* @return DataList
*/
public function removeMany($idList) {
foreach($idList as $id) {
$this->removeByID($id);
}
return $this;
}
/**
* Remove every element in this DataList matching the given $filter.
*
* @param string $filter - a sql type where filter
* @return DataList
*/
public function removeByFilter($filter) {
foreach($this->where($filter) as $item) {
$this->remove($item);
}
return $this;
}
/**
* Remove every element in this DataList.
*
* @return DataList
*/
public function removeAll() {
foreach($this as $item) {
$this->remove($item);
}
return $this;
}
/**
* This method are overloaded by HasManyList and ManyMany list to perform more sophisticated
* list manipulation
*
* @param type $item
*/
public function add($item) {
// Nothing needs to happen by default
// TO DO: If a filter is given to this data list then
}
/**
* Return a new item to add to this DataList.
*
* @todo This doesn't factor in filters.
*/
public function newObject($initialFields = null) {
$class = $this->dataClass;
return Injector::inst()->create($class, $initialFields, false, $this->model);
}
/**
* Remove this item by deleting it
*
* @param DataClass $item
* @todo Allow for amendment of this behaviour - for example, we can remove an item from
* an "ActiveItems" DataList by chaning the status to inactive.
*/
public function remove($item) {
// By default, we remove an item from a DataList by deleting it.
$this->removeByID($item->ID);
}
/**
* Remove an item from this DataList by ID
*
* @param int $itemID - The primary ID
*/
public function removeByID($itemID) {
$item = $this->byID($itemID);
if($item) return $item->delete();
}
/**
* Reverses a list of items.
*
* @return DataList
*/
public function reverse() {
return $this->alterDataQuery(function($query){
$query->reverseSort();
});
}
/**
* This method won't function on DataLists due to the specific query that it represent
*
* @param mixed $item
*/
public function push($item) {
user_error("Can't call DataList::push() because its data comes from a specific query.", E_USER_ERROR);
}
/**
* This method won't function on DataLists due to the specific query that it represent
*
* @param mixed $item
*/
public function insertFirst($item) {
user_error("Can't call DataList::insertFirst() because its data comes from a specific query.", E_USER_ERROR);
}
/**
* This method won't function on DataLists due to the specific query that it represent
*
*/
public function shift() {
user_error("Can't call DataList::shift() because its data comes from a specific query.", E_USER_ERROR);
}
/**
* This method won't function on DataLists due to the specific query that it represent
*
*/
public function replace() {
user_error("Can't call DataList::replace() because its data comes from a specific query.", E_USER_ERROR);
}
/**
* This method won't function on DataLists due to the specific query that it represent
*
*/
public function merge() {
user_error("Can't call DataList::merge() because its data comes from a specific query.", E_USER_ERROR);
}
/**
* This method won't function on DataLists due to the specific query that it represent
*
*/
public function removeDuplicates() {
user_error("Can't call DataList::removeDuplicates() because its data comes from a specific query.",
E_USER_ERROR);
}
/**
* Returns whether an item with $key exists
*
* @param mixed $key
* @return bool
*/
public function offsetExists($key) {
return ($this->limit(1,$key)->First() != null);
}
/**
* Returns item stored in list with index $key
*
* @param mixed $key
* @return DataObject
*/
public function offsetGet($key) {
return $this->limit(1, $key)->First();
}
/**
* Set an item with the key in $key
*
* @param mixed $key
* @param mixed $value
*/
public function offsetSet($key, $value) {
user_error("Can't alter items in a DataList using array-access", E_USER_ERROR);
}
/**
* Unset an item with the key in $key
*
* @param mixed $key
*/
public function offsetUnset($key) {
user_error("Can't alter items in a DataList using array-access", E_USER_ERROR);
}
}