eloquent with() in multiple where() clouse - laravel

Question

I am trying to filter results of relationship table.
public function read_projects_by_coords(Request $request)
{
$from_lat = $request->get("from_lat");
$to_lat = $request->get('to_lat');
$from_lng = $request->get('from_lng');
$to_lng = $request->get('to_lng');
$projects = Project::with(["details" => function($query) use ($from_lat, $from_lng, $to_lat, $to_lng){
return $query->where("details.lat", ">", $from_lat)
->where("details.lat", "<", $to_lat)
->where("details.lng", ">", $from_lng)
->where("details.lng", "<", $to_lng);
}])->get();
return response()->json($projects);
}
But when I run the above details(child) coming with a empty/null result and parent/Project table not filtered. I returns all...
For example $projects = Project::with(["details"])->get(); this is works without a problem. But when I try to filter Project Model with the where inside the with() I can't get the detail object records, and parent is not filtered.
to anyone who wants to see the models parent and child
class Project extends Model
{
protected $table = "projects";
protected $guarded = [];
protected $with = ["details"];
public function details(){
return $this->hasOne("App\Models\Detail");
}
}
class Detail extends Model
{
protected $table = "details";
protected $guarded = [];
public function project(){
return $this->belongsTo("App\Models\Project");
}
}
What am I am missing?

Answer 1

To filter the Project table to only select the ones with some Details matching your parameters, you need to use whereHas. You need to keep your with clause too in order to have the details property correctly populated.
I would use a callback to not repeat the same conditions
$callback = function($query) use ($from_lat, $from_lng, $to_lat, $to_lng) {
$query->where("lat", ">", $from_lat)
->where("lat", "<", $to_lat)
->where("lng", ">", $from_lng)
->where("lng", "<", $to_lng);
}
$projects = Project::with(['details' => $callback])
->whereHas('details', $callback)
->get();
return response()->json($projects);