Файл: framework/model/ManyManyList.php
Строк: 459
<?php
/**
* Subclass of {@link DataList} representing a many_many relation.
*
* @package framework
* @subpackage model
*/
class ManyManyList extends RelationList {
/**
* @var string $joinTable
*/
protected $joinTable;
/**
* @var string $localKey
*/
protected $localKey;
/**
* @var string $foreignKey
*/
protected $foreignKey;
/**
* @var array $extraFields
*/
protected $extraFields;
/**
* @var array $_compositeExtraFields
*/
protected $_compositeExtraFields = array();
/**
* Create a new ManyManyList object.
*
* A ManyManyList object represents a list of {@link DataObject} records
* that correspond to a many-many relationship.
*
* Generation of the appropriate record set is left up to the caller, using
* the normal {@link DataList} methods. Addition arguments are used to
* support {@@link add()} and {@link remove()} methods.
*
* @param string $dataClass The class of the DataObjects that this will list.
* @param string $joinTable The name of the table whose entries define the content of this many_many relation.
* @param string $localKey The key in the join table that maps to the dataClass' PK.
* @param string $foreignKey The key in the join table that maps to joined class' PK.
* @param string $extraFields A map of field => fieldtype of extra fields on the join table.
*
* @example new ManyManyList('Group','Group_Members', 'GroupID', 'MemberID');
*/
public function __construct($dataClass, $joinTable, $localKey, $foreignKey, $extraFields = array()) {
parent::__construct($dataClass);
$this->joinTable = $joinTable;
$this->localKey = $localKey;
$this->foreignKey = $foreignKey;
$this->extraFields = $extraFields;
$this->linkJoinTable();
}
/**
* Setup the join between this dataobject and the necessary mapping table
*/
protected function linkJoinTable() {
// Join to the many-many join table
$baseClass = ClassInfo::baseDataClass($this->dataClass);
$this->dataQuery->innerJoin($this->joinTable, ""{$this->joinTable}"."{$this->localKey}" = "{$baseClass}"."ID"");
// Add the extra fields to the query
if($this->extraFields) {
$this->appendExtraFieldsToQuery();
}
}
/**
* Adds the many_many_extraFields to the select of the underlying
* {@link DataQuery}.
*
* @return void
*/
protected function appendExtraFieldsToQuery() {
$finalized = array();
foreach($this->extraFields as $field => $spec) {
$obj = Object::create_from_string($spec);
if($obj instanceof CompositeDBField) {
$this->_compositeExtraFields[$field] = array();
// append the composite field names to the select
foreach($obj->compositeDatabaseFields() as $subField => $subSpec) {
$col = $field . $subField;
$finalized[] = $col;
// cache
$this->_compositeExtraFields[$field][] = $subField;
}
} else {
$finalized[] = $field;
}
}
$this->dataQuery->selectFromTable($this->joinTable, $finalized);
}
/**
* Create a DataObject from the given SQL row.
*
* @param array $row
* @return DataObject
*/
protected function createDataObject($row) {
// remove any composed fields
$add = array();
if($this->_compositeExtraFields) {
foreach($this->_compositeExtraFields as $fieldName => $composed) {
// convert joined extra fields into their composite field types.
$value = array();
foreach($composed as $subField => $subSpec) {
if(isset($row[$fieldName . $subSpec])) {
$value[$subSpec] = $row[$fieldName . $subSpec];
// don't duplicate data in the record
unset($row[$fieldName . $subSpec]);
}
}
$obj = Object::create_from_string($this->extraFields[$fieldName], $fieldName);
$obj->setValue($value, null, false);
$add[$fieldName] = $obj;
}
}
$dataObject = parent::createDataObject($row);
foreach($add as $fieldName => $obj) {
$dataObject->$fieldName = $obj;
}
return $dataObject;
}
/**
* Return a filter expression for when getting the contents of the
* relationship for some foreign ID
*
* @param int $id
*
* @return string
*/
protected function foreignIDFilter($id = null) {
if ($id === null) {
$id = $this->getForeignID();
}
// Apply relation filter
$key = ""{$this->joinTable}"."{$this->foreignKey}"";
if(is_array($id)) {
return array("$key IN (".DB::placeholders($id).")" => $id);
} else if($id !== null){
return array($key => $id);
}
}
/**
* Return a filter expression for the join table when writing to the join table
*
* When writing (add, remove, removeByID), we need to filter the join table to just the relevant
* entries. However some subclasses of ManyManyList (Member_GroupSet) modify foreignIDFilter to
* include additional calculated entries, so we need different filters when reading and when writing
*
* @param array|integer $id (optional) An ID or an array of IDs - if not provided, will use the current ids
* as per getForeignID
* @return array Condition In array(SQL => parameters format)
*/
protected function foreignIDWriteFilter($id = null) {
return $this->foreignIDFilter($id);
}
/**
* Add an item to this many_many relationship
* Does so by adding an entry to the joinTable.
*
* @param mixed $item
* @param array $extraFields A map of additional columns to insert into the joinTable.
* Column names should be ANSI quoted.
*/
public function add($item, $extraFields = array()) {
// Ensure nulls or empty strings are correctly treated as empty arrays
if(empty($extraFields)) $extraFields = array();
// Determine ID of new record
if(is_numeric($item)) {
$itemID = $item;
} elseif($item instanceof $this->dataClass) {
$itemID = $item->ID;
} else {
throw new InvalidArgumentException("ManyManyList::add() expecting a $this->dataClass object, or ID value",
E_USER_ERROR);
}
// Validate foreignID
$foreignIDs = $this->getForeignID();
if(empty($foreignIDs)) {
throw new Exception("ManyManyList::add() can't be called until a foreign ID is set", E_USER_WARNING);
}
// Apply this item to each given foreign ID record
if(!is_array($foreignIDs)) $foreignIDs = array($foreignIDs);
foreach($foreignIDs as $foreignID) {
// Check for existing records for this item
if($foreignFilter = $this->foreignIDWriteFilter($foreignID)) {
// With the current query, simply add the foreign and local conditions
// The query can be a bit odd, especially if custom relation classes
// don't join expected tables (@see Member_GroupSet for example).
$query = new SQLQuery("*", ""{$this->joinTable}"");
$query->addWhere($foreignFilter);
$query->addWhere(array(
""{$this->joinTable}"."{$this->localKey}"" => $itemID
));
$hasExisting = ($query->count() > 0);
} else {
$hasExisting = false;
}
// Blank manipulation
$manipulation = array(
$this->joinTable => array(
'command' => $hasExisting ? 'update' : 'insert',
'fields' => array()
)
);
if($hasExisting) {
$manipulation[$this->joinTable]['where'] = array(
""{$this->joinTable}"."{$this->foreignKey}"" => $foreignID,
""{$this->joinTable}"."{$this->localKey}"" => $itemID
);
}
if($extraFields && $this->extraFields) {
// Write extra field to manipluation in the same way
// that DataObject::prepareManipulationTable writes fields
foreach($this->extraFields as $fieldName => $fieldSpec) {
// Skip fields without an assignment
if(array_key_exists($fieldName, $extraFields)) {
$fieldObject = Object::create_from_string($fieldSpec, $fieldName);
$fieldObject->setValue($extraFields[$fieldName]);
$fieldObject->writeToManipulation($manipulation[$this->joinTable]);
}
}
}
$manipulation[$this->joinTable]['fields'][$this->localKey] = $itemID;
$manipulation[$this->joinTable]['fields'][$this->foreignKey] = $foreignID;
DB::manipulate($manipulation);
}
}
/**
* Remove the given item from this list.
*
* Note that for a ManyManyList, the item is never actually deleted, only
* the join table is affected.
*
* @param DataObject $item
*/
public function remove($item) {
if(!($item instanceof $this->dataClass)) {
throw new InvalidArgumentException("ManyManyList::remove() expecting a $this->dataClass object");
}
return $this->removeByID($item->ID);
}
/**
* Remove the given item from this list.
*
* Note that for a ManyManyList, the item is never actually deleted, only
* the join table is affected
*
* @param int $itemID The item ID
*/
public function removeByID($itemID) {
if(!is_numeric($itemID)) throw new InvalidArgumentException("ManyManyList::removeById() expecting an ID");
$query = new SQLDelete(""{$this->joinTable}"");
if($filter = $this->foreignIDWriteFilter($this->getForeignID())) {
$query->setWhere($filter);
} else {
user_error("Can't call ManyManyList::remove() until a foreign ID is set", E_USER_WARNING);
}
$query->addWhere(array(""{$this->localKey}"" => $itemID));
$query->execute();
}
/**
* Remove all items from this many-many join. To remove a subset of items,
* filter it first.
*
* @return void
*/
public function removeAll() {
$base = ClassInfo::baseDataClass($this->dataClass());
// Remove the join to the join table to avoid MySQL row locking issues.
$query = $this->dataQuery();
$foreignFilter = $query->getQueryParam('Foreign.Filter');
$query->removeFilterOn($foreignFilter);
$selectQuery = $query->query();
$selectQuery->setSelect(""{$base}"."ID"");
$from = $selectQuery->getFrom();
unset($from[$this->joinTable]);
$selectQuery->setFrom($from);
$selectQuery->setOrderBy(); // ORDER BY in subselects breaks MS SQL Server and is not necessary here
$selectQuery->setDistinct(false);
// Use a sub-query as SQLite does not support setting delete targets in
// joined queries.
$delete = new SQLDelete();
$delete->setFrom(""{$this->joinTable}"");
$delete->addWhere($this->foreignIDFilter());
$subSelect = $selectQuery->sql($parameters);
$delete->addWhere(array(
""{$this->joinTable}"."{$this->localKey}" IN ($subSelect)" => $parameters
));
$delete->execute();
}
/**
* Find the extra field data for a single row of the relationship join
* table, given the known child ID.
*
* @param string $componentName The name of the component
* @param int $itemID The ID of the child for the relationship
*
* @return array Map of fieldName => fieldValue
*/
public function getExtraData($componentName, $itemID) {
$result = array();
// Skip if no extrafields or unsaved record
if(empty($this->extraFields) || empty($itemID)) {
return $result;
}
if(!is_numeric($itemID)) {
user_error('ComponentSet::getExtraData() passed a non-numeric child ID', E_USER_ERROR);
}
$cleanExtraFields = array();
foreach ($this->extraFields as $fieldName => $dbFieldSpec) {
$cleanExtraFields[] = ""{$fieldName}"";
}
$query = new SQLQuery($cleanExtraFields, ""{$this->joinTable}"");
$filter = $this->foreignIDWriteFilter($this->getForeignID());
if($filter) {
$query->setWhere($filter);
} else {
user_error("Can't call ManyManyList::getExtraData() until a foreign ID is set", E_USER_WARNING);
}
$query->addWhere(array(
""{$this->localKey}"" => $itemID
));
$queryResult = $query->execute()->current();
if ($queryResult) {
foreach ($queryResult as $fieldName => $value) {
$result[$fieldName] = $value;
}
}
return $result;
}
/**
* Gets the join table used for the relationship.
*
* @return string the name of the table
*/
public function getJoinTable() {
return $this->joinTable;
}
/**
* Gets the key used to store the ID of the local/parent object.
*
* @return string the field name
*/
public function getLocalKey() {
return $this->localKey;
}
/**
* Gets the key used to store the ID of the foreign/child object.
*
* @return string the field name
*/
public function getForeignKey() {
return $this->foreignKey;
}
/**
* Gets the extra fields included in the relationship.
*
* @return array a map of field names to types
*/
public function getExtraFields() {
return $this->extraFields;
}
}