Laravel: Tree filter children recursive - php

Question

I cannot seem to apply filtering on all children defined in a tree model format with eager loading mechanism
Here is my model definition (works great):
class Section extends Model
{
[...]
/**
* #return HasOne
*/
public function parent()
{
return $this->hasOne(
self::class,
'Id',
'IdParent'
)->with('parent');
}
/**
* #return HasMany
*/
public function children()
{
return $this->hasMany(
self::class,
'IdParent',
'Id'
)->with('children');
}
[...]
}
Now I want to filter out recursive based on a 'criteria object'
public function getMachines(SectionCriteria $sectionCriteria = NULL)
{
/**
* #var $builder Builder|Section
*/
$builder = Section::with([
'children' => function ($query) use ($sectionCriteria) {
if ($sectionCriteria) {
foreach ($sectionCriteria->getFilterFlags() as $flagName => $flagValue) {
if ($flagValue) {
$query->whereFlag($flagName); //Custom implementation
} else {
$query->whereNotFlag($flagName); //Custom implementation
}
}
}
}
]);
This works bot it is applied to the first level of the tree.
My question would be: Is there a way to pass an object to the children() relation so I can apply filters recursive (which would apply to all levels)?
Something like, let's say:
P.S: This is not possible since only a callback is accepted as a parameter
public function children($parameters)
{
return $this->hasMany(
self::class,
'IdParent',
'Id'
)->with('children'=>$parameters);
}
What I wouldn't want to use (with respect to SOLID principles):
Make a static class variable which holds criteria
A global variable of any kind

Answer 1

I also tried to retrieve children recursive (and apply filters) but ended up with more queries so Eloquent is preety well optimized sooo...
I used technique #1 (Make a static class variable) though I do not really like it but it works.
Model
/**
* #var null|SectionCriteria
*/
public static $childrenFilter = NULL; //This can be whatever you need since it's static
/**
* #return HasMany
*/
public function children()
{
return $this->hasMany(
self::class,
'IdParent',
'Id'
)->with(['children'=>self::searchChild()]);
}
/**
* #return \Closure
*/
public function searchChild()
{
return function ($builder) {
if (Section::$childrenFilter) {
foreach ($sectionCriteria->getFilterFlags() as $flagName => $flagValue) {
if ($flagValue) {
$query->whereFlag($flagName); //Custom implementation
} else {
$query->whereNotFlag($flagName); //Custom implementation
}
}
}
};
}
/**
* #param SectionCriteria $criteria
*/
public static function setChildSearch(SectionCriteria $criteria)
{
Section::$childrenFilter = $criteria;
}
/**
* Remove the search criteria filter
*/
public static function clearChildSearch()
{
Section::$childrenFilter = NULL;
}
Repository (the actual usage)
/**
* #param SectionCriteria|NULL $sectionCriteria
* #return Section[]|Collection
*/
public function getMachines(SectionCriteria $sectionCriteria = NULL)
{
/**
* #var $builder Builder|Section
*/
$builder = Section::with(['children']); //Here I do not need the root elements to be filtered, If needed then use: Section::with(['children'=>Section::searchChild()])
Section::setChildSearch($sectionCriteria);
$builder->orderBy('Name');
$results = $builder->get();
Section::clearChildSearch();
return $results;
}
Again...not preety but it gets the job done
New: Another way (will test this out) would be to extend the Builder class