<?php
namespace Illuminate\Database\Eloquent\Relations;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Database\Eloquent\Collection;
use Illuminate\Database\Eloquent\SoftDeletes;
use Illuminate\Database\Eloquent\ModelNotFoundException;
class HasManyThrough extends Relation
{
/**
* The "through" parent model instance.
*
* @var \Illuminate\Database\Eloquent\Model
*/
protected $throughParent;
/**
* The far parent model instance.
*
* @var \Illuminate\Database\Eloquent\Model
*/
protected $farParent;
/**
* The near key on the relationship.
*
* @var string
*/
protected $firstKey;
/**
* The far key on the relationship.
*
* @var string
*/
protected $secondKey;
/**
* The local key on the relationship.
*
* @var string
*/
protected $localKey;
/**
* The local key on the intermediary model.
*
* @var string
*/
protected $secondLocalKey;
/**
* The count of self joins.
*
* @var int
*/
protected static $selfJoinCount = 0;
/**
* Create a new has many through relationship instance.
*
* @param \Illuminate\Database\Eloquent\Builder $query
* @param \Illuminate\Database\Eloquent\Model $farParent
* @param \Illuminate\Database\Eloquent\Model $throughParent
* @param string $firstKey
* @param string $secondKey
* @param string $localKey
* @param string $secondLocalKey
* @return void
*/
public function __construct(Builder $query, Model $farParent, Model $throughParent, $firstKey, $secondKey, $localKey, $secondLocalKey)
{
$this->localKey = $localKey;
$this->firstKey = $firstKey;
$this->secondKey = $secondKey;
$this->farParent = $farParent;
$this->throughParent = $throughParent;
$this->secondLocalKey = $secondLocalKey;
parent::__construct($query, $throughParent);
}
/**
* Set the base constraints on the relation query.
*
* @return void
*/
public function addConstraints()
{
$localValue = $this->farParent[$this->localKey];
$this->performJoin();
if (static::$constraints) {
$this->query->where($this->getQualifiedFirstKeyName(), '=', $localValue);
}
}
/**
* Set the join clause on the query.
*
* @param \Illuminate\Database\Eloquent\Builder|null $query
* @return void
*/
protected function performJoin(Builder $query = null)
{
$query = $query ?: $this->query;
$farKey = $this->getQualifiedFarKeyName();
$query->join($this->throughParent->getTable(), $this->getQualifiedParentKeyName(), '=', $farKey);
if ($this->throughParentSoftDeletes()) {
$query->whereNull($this->throughParent->getQualifiedDeletedAtColumn());
}
}
/**
* Get the fully qualified parent key name.
*
* @return string
*/
public function getQualifiedParentKeyName()
{
return $this->parent->qualifyColumn($this->secondLocalKey);
}
/**
* Determine whether "through" parent of the relation uses Soft Deletes.
*
* @return bool
*/
public function throughParentSoftDeletes()
{
return in_array(SoftDeletes::class, class_uses_recursive($this->throughParent));
}
/**
* Set the constraints for an eager load of the relation.
*
* @param array $models
* @return void
*/
public function addEagerConstraints(array $models)
{
$this->query->whereIn(
$this->getQualifiedFirstKeyName(), $this->getKeys($models, $this->localKey)
);
}
/**
* Initialize the relation on a set of models.
*
* @param array $models
* @param string $relation
* @return array
*/
public function initRelation(array $models, $relation)
{
foreach ($models as $model) {
$model->setRelation($relation, $this->related->newCollection());
}
return $models;
}
/**
* Match the eagerly loaded results to their parents.
*
* @param array $models
* @param \Illuminate\Database\Eloquent\Collection $results
* @param string $relation
* @return array
*/
public function match(array $models, Collection $results, $relation)
{
$dictionary = $this->buildDictionary($results);
// Once we have the dictionary we can simply spin through the parent models to
// link them up with their children using the keyed dictionary to make the
// matching very convenient and easy work. Then we'll just return them.
foreach ($models as $model) {
if (isset($dictionary[$key = $model->getAttribute($this->localKey)])) {
$model->setRelation(
$relation, $this->related->newCollection($dictionary[$key])
);
}
}
return $models;
}
/**
* Build model dictionary keyed by the relation's foreign key.
*
* @param \Illuminate\Database\Eloquent\Collection $results
* @return array
*/
protected function buildDictionary(Collection $results)
{
$dictionary = [];
// First we will create a dictionary of models keyed by the foreign key of the
// relationship as this will allow us to quickly access all of the related
// models without having to do nested looping which will be quite slow.
foreach ($results as $result) {
$dictionary[$result->{$this->firstKey}][] = $result;
}
return $dictionary;
}
/**
* Get the first related model record matching the attributes or instantiate it.
*
* @param array $attributes
* @return \Illuminate\Database\Eloquent\Model
*/
public function firstOrNew(array $attributes)
{
if (is_null($instance = $this->where($attributes)->first())) {
$instance = $this->related->newInstance($attributes);
}
return $instance;
}
/**
* Create or update a related record matching the attributes, and fill it with values.
*
* @param array $attributes
* @param array $values
* @return \Illuminate\Database\Eloquent\Model
*/
public function updateOrCreate(array $attributes, array $values = [])
{
$instance = $this->firstOrNew($attributes);
$instance->fill($values)->save();
return $instance;
}
/**
* Execute the query and get the first related model.
*
* @param array $columns
* @return mixed
*/
public function first($columns = ['*'])
{
$results = $this->take(1)->get($columns);
return count($results) > 0 ? $results->first() : null;
}
/**
* Execute the query and get the first result or throw an exception.
*
* @param array $columns
* @return \Illuminate\Database\Eloquent\Model|static
*
* @throws \Illuminate\Database\Eloquent\ModelNotFoundException
*/
public function firstOrFail($columns = ['*'])
{
if (! is_null($model = $this->first($columns))) {
return $model;
}
throw (new ModelNotFoundException)->setModel(get_class($this->related));
}
/**
* Find a related model by its primary key.
*
* @param mixed $id
* @param array $columns
* @return \Illuminate\Database\Eloquent\Model|\Illuminate\Database\Eloquent\Collection|null
*/
public function find($id, $columns = ['*'])
{
if (is_array($id)) {
return $this->findMany($id, $columns);
}
return $this->where(
$this->getRelated()->getQualifiedKeyName(), '=', $id
)->first($columns);
}
/**
* Find multiple related models by their primary keys.
*
* @param mixed $ids
* @param array $columns
* @return \Illuminate\Database\Eloquent\Collection
*/
public function findMany($ids, $columns = ['*'])
{
if (empty($ids)) {
return $this->getRelated()->newCollection();
}
return $this->whereIn(
$this->getRelated()->getQualifiedKeyName(), $ids
)->get($columns);
}
/**
* Find a related model by its primary key or throw an exception.
*
* @param mixed $id
* @param array $columns
* @return \Illuminate\Database\Eloquent\Model|\Illuminate\Database\Eloquent\Collection
*
* @throws \Illuminate\Database\Eloquent\ModelNotFoundException
*/
public function findOrFail($id, $columns = ['*'])
{
$result = $this->find($id, $columns);
if (is_array($id)) {
if (count($result) === count(array_unique($id))) {
return $result;
}
} elseif (! is_null($result)) {
return $result;
}
throw (new ModelNotFoundException)->setModel(get_class($this->related), $id);
}
/**
* Get the results of the relationship.
*
* @return mixed
*/
public function getResults()
{
return $this->get();
}
/**
* Execute the query as a "select" statement.
*
* @param array $columns
* @return \Illuminate\Database\Eloquent\Collection
*/
public function get($columns = ['*'])
{
$builder = $this->prepareQueryBuilder($columns);
$models = $builder->getModels();
// If we actually found models we will also eager load any relationships that
// have been specified as needing to be eager loaded. This will solve the
// n + 1 query problem for the developer and also increase performance.
if (count($models) > 0) {
$models = $builder->eagerLoadRelations($models);
}
return $this->related->newCollection($models);
}
/**
* Get a paginator for the "select" statement.
*
* @param int $perPage
* @param array $columns
* @param string $pageName
* @param int $page
* @return \Illuminate\Contracts\Pagination\LengthAwarePaginator
*/
public function paginate($perPage = null, $columns = ['*'], $pageName = 'page', $page = null)
{
$this->query->addSelect($this->shouldSelect($columns));
return $this->query->paginate($perPage, $columns, $pageName, $page);
}
/**
* Paginate the given query into a simple paginator.
*
* @param int $perPage
* @param array $columns
* @param string $pageName
* @param int|null $page
* @return \Illuminate\Contracts\Pagination\Paginator
*/
public function simplePaginate($perPage = null, $columns = ['*'], $pageName = 'page', $page = null)
{
$this->query->addSelect($this->shouldSelect($columns));
return $this->query->simplePaginate($perPage, $columns, $pageName, $page);
}
/**
* Set the select clause for the relation query.
*
* @param array $columns
* @return array
*/
protected function shouldSelect(array $columns = ['*'])
{
if ($columns == ['*']) {
$columns = [$this->related->getTable().'.*'];
}
return array_merge($columns, [$this->getQualifiedFirstKeyName()]);
}
/**
* Chunk the results of the query.
*
* @param int $count
* @param callable $callback
* @return bool
*/
public function chunk($count, callable $callback)
{
return $this->prepareQueryBuilder()->chunk($count, $callback);
}
/**
* Get a generator for the given query.
*
* @return \Generator
*/
public function cursor()
{
return $this->prepareQueryBuilder()->cursor();
}
/**
* Execute a callback over each item while chunking.
*
* @param callable $callback
* @param int $count
* @return bool
*/
public function each(callable $callback, $count = 1000)
{
return $this->chunk($count, function ($results) use ($callback) {
foreach ($results as $key => $value) {
if ($callback($value, $key) === false) {
return false;
}
}
});
}
/**
* Prepare the query builder for query execution.
*
* @param array $columns
* @return \Illuminate\Database\Eloquent\Builder
*/
protected function prepareQueryBuilder($columns = ['*'])
{
$builder = $this->query->applyScopes();
return $builder->addSelect(
$this->shouldSelect($builder->getQuery()->columns ? [] : $columns)
);
}
/**
* Add the constraints for a relationship query.
*
* @param \Illuminate\Database\Eloquent\Builder $query
* @param \Illuminate\Database\Eloquent\Builder $parentQuery
* @param array|mixed $columns
* @return \Illuminate\Database\Eloquent\Builder
*/
public function getRelationExistenceQuery(Builder $query, Builder $parentQuery, $columns = ['*'])
{
if ($parentQuery->getQuery()->from == $query->getQuery()->from) {
return $this->getRelationExistenceQueryForSelfRelation($query, $parentQuery, $columns);
}
$this->performJoin($query);
return $query->select($columns)->whereColumn(
$this->getQualifiedLocalKeyName(), '=', $this->getQualifiedFirstKeyName()
);
}
/**
* Add the constraints for a relationship query on the same table.
*
* @param \Illuminate\Database\Eloquent\Builder $query
* @param \Illuminate\Database\Eloquent\Builder $parentQuery
* @param array|mixed $columns
* @return \Illuminate\Database\Eloquent\Builder
*/
public function getRelationExistenceQueryForSelfRelation(Builder $query, Builder $parentQuery, $columns = ['*'])
{
$query->from($query->getModel()->getTable().' as '.$hash = $this->getRelationCountHash());
$query->join($this->throughParent->getTable(), $this->getQualifiedParentKeyName(), '=', $hash.'.'.$this->secondLocalKey);
if ($this->throughParentSoftDeletes()) {
$query->whereNull($this->throughParent->getQualifiedDeletedAtColumn());
}
$query->getModel()->setTable($hash);
return $query->select($columns)->whereColumn(
$parentQuery->getQuery()->from.'.'.$this->localKey, '=', $this->getQualifiedFirstKeyName()
);
}
/**
* Get a relationship join table hash.
*
* @return string
*/
public function getRelationCountHash()
{
return 'laravel_reserved_'.static::$selfJoinCount++;
}
/**
* Get the qualified foreign key on the related model.
*
* @return string
*/
public function getQualifiedFarKeyName()
{
return $this->getQualifiedForeignKeyName();
}
/**
* Get the qualified foreign key on the "through" model.
*
* @return string
*/
public function getQualifiedFirstKeyName()
{
return $this->throughParent->qualifyColumn($this->firstKey);
}
/**
* Get the qualified foreign key on the related model.
*
* @return string
*/
public function getQualifiedForeignKeyName()
{
return $this->related->qualifyColumn($this->secondKey);
}
/**
* Get the qualified local key on the far parent model.
*
* @return string
*/
public function getQualifiedLocalKeyName()
{
return $this->farParent->qualifyColumn($this->localKey);
}
}