silverstripe-framework/model/DataList.php

472 lines
11 KiB
PHP

<?php
/**
* Implements a "lazy loading" DataObjectSet.
* Uses {@link DataQuery} to do the actual query generation.
*/
class DataList extends ViewableData implements SS_List {
/**
* The DataObject class name that this data list is querying
*/
protected $dataClass;
/**
* The {@link DataQuery} object responsible for getting this DataObjectSet's records
*/
protected $dataQuery;
/**
* The DataModel from which this DataList comes.
*/
protected $model;
/**
* Synonym of the constructor. Can be chained with literate methods.
* DataList::create("SiteTree")->sort("Title") is legal, but
* new DataList("SiteTree")->sort("Title") is not.
*/
static function create($dataClass) {
return new DataList($dataClass);
}
/**
* Create a new DataList.
* No querying is done on construction, but the initial query schema is set up.
* @param $dataClass The DataObject class to query.
*/
public function __construct($dataClass) {
$this->dataClass = $dataClass;
$this->dataQuery = new DataQuery($this->dataClass);
parent::__construct();
}
public function setModel(DataModel $model) {
$this->model = $model;
}
public function dataClass() {
return $this->dataClass;
}
/**
* Clone this object
*/
function __clone() {
$this->dataQuery = clone $this->dataQuery;
}
/**
* Return the internal {@link DataQuery} object for direct manipulation
*/
public function dataQuery() {
return $this->dataQuery;
}
/**
* Returns the SQL query that will be used to get this DataList's records. Good for debugging. :-)
*/
public function sql() {
return $this->dataQuery->query()->sql();
}
/**
* Add a WHERE clause to the query.
*
* @param string $filter
*/
public function where($filter) {
$this->dataQuery->where($filter);
return $this;
}
/**
* Set the sort order of this data list
*/
public function sort($sort, $direction = "ASC") {
if($direction && strtoupper($direction) != 'ASC') $sort = "$sort $direction";
$this->dataQuery->sort($sort);
return $this;
}
/**
* Returns true if this DataList can be sorted by the given field.
*/
public function canSortBy($field) {
return $this->dataQuery()->query()->canSortBy($field);
}
/**
* Add an join clause to this data list's query.
*/
public function join($join) {
$this->dataQuery->join($join);
return $this;
}
/**
* Restrict the records returned in this query by a limit clause
*/
public function limit($limit) {
$this->dataQuery->limit($limit);
return $this;
}
/**
* Add an inner join clause to this data list's query.
*/
public function innerJoin($table, $onClause, $alias = null) {
$this->dataQuery->innerJoin($table, $onClause, $alias);
return $this;
}
/**
* Add an left join clause to this data list's query.
*/
public function leftJoin($table, $onClause, $alias = null) {
$this->dataQuery->leftJoin($table, $onClause, $alias);
return $this;
}
/**
* 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;
}
public function toNestedArray() {
$result = array();
foreach ($this as $item) {
$result[] = $item->toMap();
}
return $result;
}
public function map($keyfield = 'ID', $titlefield = 'Title') {
$map = array();
foreach ($this as $item) {
$map[$item->$keyfield] = $item->$titlefield;
}
return $map;
}
/**
* Create a data object from the given SQL row
*/
protected function createDataObject($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 = new $row['RecordClassName']($row, false, $this->model);
else $item = new $defaultClass($row, false, $this->model);
return $item;
}
/**
* Returns an Iterator for this DataObjectSet.
* This function allows you to use DataObjectSets in foreach loops
* @return DataObjectSet_Iterator
*/
public function getIterator() {
return new ArrayIterator($this->toArray());
}
/**
* Return the number of items in this DataList
*/
function count() {
return $this->dataQuery->count();
}
/**
* Return the maximum value of the given field in this DataList
*/
function Max($field) {
return $this->dataQuery->max($field);
}
/**
* Return the minimum value of the given field in this DataList
*/
function Min($field) {
return $this->dataQuery->min($field);
}
/**
* Return the average value of the given field in this DataList
*/
function Avg($field) {
return $this->dataQuery->avg($field);
}
/**
* Return the sum of the values of the given field in this DataList
*/
function Sum($field) {
return $this->dataQuery->sum($field);
}
/**
* Returns the first item in this DataList
*/
function First() {
foreach($this->dataQuery->firstRow()->execute() as $row) {
return $this->createDataObject($row);
}
}
/**
* Returns the last item in this DataList
*/
function Last() {
foreach($this->dataQuery->lastRow()->execute() as $row) {
return $this->createDataObject($row);
}
}
/**
* Returns true if this DataList has items
*/
function exists() {
return $this->count() > 0;
}
/**
* Get a sub-range of this dataobjectset as an array
*/
public function getRange($offset, $length) {
return $this->limit(array('start' => $offset, 'limit' => $length));
}
/**
* Find an element of this DataList where the given key = value
*/
public function find($key, $value) {
return $this->where("\"$key\" = '" . Convert::raw2sql($value) . "'")->First();
}
/**
* Filter this list to only contain the given IDs
*/
public function byIDs(array $ids) {
$baseClass = ClassInfo::baseDataClass($this->dataClass);
$this->where("\"$baseClass\".\"ID\" IN (" . implode(',', $ids) .")");
return $this;
}
/**
* Return the item of the given ID
*/
public function byID($id) {
$baseClass = ClassInfo::baseDataClass($this->dataClass);
return $this->where("\"$baseClass\".\"ID\" = " . (int)$id)->First();
}
/**
* Return a single column from this DataList.
* @param $colNum The DataObject field to return.
*/
function column($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 $idList List of IDs.
*/
function setByIDList($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.
*/
function getIDList() {
$ids = $this->column("ID");
return $ids ? array_combine($ids, $ids) : array();
}
/**
* Returns a HasManyList or ManyMany list representing the querying of a relation across all
* objects in this data list. For it to work, the relation must be defined on the data class
* that you used to create this DataList.
*
* Example: Get members from all Groups:
*
* DataObject::get("Group")->relation("Members")
*/
function relation($relationName) {
$ids = $this->column('ID');
return singleton($this->dataClass)->$relationName()->forForeignID($ids);
}
/**
* Add a number of items to the component set.
* @param array $items Items to add, as either DataObjects or IDs.
*/
function addMany($items) {
foreach($items as $item) {
$this->add($item);
}
}
/**
* Remove the items from this list with the given IDs
*/
function removeMany($idList) {
foreach($idList as $id) {
$this->removeByID($id);
}
}
/**
* Remove every element in this DataList matching the given $filter.
*/
function removeByFilter($filter) {
foreach($this->where($filter) as $item) {
$this->remove($item);
}
}
/**
* Remove every element in this DataList.
*/
function removeAll() {
foreach($this as $item) {
$this->remove($item);
}
}
// These methods are overloaded by HasManyList and ManyMany list to perform
// more sophisticated list manipulation
function add($item) {
// Nothing needs to happen by default
// TO DO: If a filter is given to this data list then
}
/**
* Return a new item to add to this DataList.
* @todo This doesn't factor in filters.
*/
function newObject($initialFields = null) {
$class = $this->dataClass;
return new $class($initialFields, false, $this->model);
}
function remove($item) {
// TO DO: Allow for amendment of this behaviour - for exmaple, we can remove an item from
// an "ActiveItems" DataList by chaning the status to inactive.
// By default, we remove an item from a DataList by deleting it.
if($item instanceof $this->dataClass) $item->delete();
}
/**
* Remove an item from this DataList by ID
*/
function removeByID($itemID) {
$item = $this->byID($itemID);
if($item) return $item->delete();
}
// Methods that won't function on DataLists
function push($item) {
user_error("Can't call DataList::push() because its data comes from a specific query.", E_USER_ERROR);
}
function insertFirst($item) {
user_error("Can't call DataList::insertFirst() because its data comes from a specific query.", E_USER_ERROR);
}
function shift() {
user_error("Can't call DataList::shift() because its data comes from a specific query.", E_USER_ERROR);
}
function replace() {
user_error("Can't call DataList::replace() because its data comes from a specific query.", E_USER_ERROR);
}
function merge() {
user_error("Can't call DataList::merge() because its data comes from a specific query.", E_USER_ERROR);
}
function removeDuplicates() {
user_error("Can't call DataList::removeDuplicates() because its data comes from a specific query.", E_USER_ERROR);
}
/**
* Necessary for interface ArrayAccess. Returns whether an item with $key exists
* @param mixed $key
* @return bool
*/
public function offsetExists($key) {
return ($this->getRange($key, 1)->First() != null);
}
/**
* Necessary for interface ArrayAccess. Returns item stored in array with index $key
* @param mixed $key
* @return DataObject
*/
public function offsetGet($key) {
return $this->getRange($key, 1)->First();
}
/**
* Necessary for interface ArrayAccess. Set an item with the key in $key
* @param mixed $key
* @param mixed $value
*/
public function offsetSet($key, $value) {
throw new Exception("Can't alter items in a DataList using array-access");
}
/**
* Necessary for interface ArrayAccess. Unset an item with the key in $key
* @param mixed $key
*/
public function offsetUnset($key) {
throw new Exception("Can't alter items in a DataList using array-access");
}
}
?>