Laravel Eloquent - 胡萝卜素配方和分页

Question

Code Review

I have created a topic on Code Review branch.

Question

I'm using haversine formula to count distance from selected post-code to desired destination.

App\Models\Business.php

public function scopeDistance($query, $latitude, $longitude, $radius)
{
    $query->getQuery()->orders = [];
    return $query->select('*')
                 ->selectRaw("( 3959 * acos( cos( radians($latitude) ) * cos( radians( latitude ) )  * cos( radians( longitude ) - radians($longitude) ) + sin( radians($latitude) ) * sin(radians(latitude)) ) ) AS distance")
                 ->having('distance', '<=', $radius)
                 ->orderBy('distance');
}

Everything seems pretty ok, except when i use paginate() method instead of get()

I have been looking for solution, there are lots of topics describing this problem, but seems that people didn't come up with good solution for it.

Some solutions in my case caused incorrect values. Maybe i did something wrong - not sure...

However i came up with this solution and i would like to hear any feedback if it's ok in terms of performance and memory usage.

function custom_paginator($builder, $per_page)
{
    $path = current_route();
    $current_page = \Illuminate\Pagination\Paginator::resolveCurrentPage();

    if ( ! isset($builder->getQuery()->columns[1])) $count = $builder->count();
    else
    {
        $query = clone $builder->getQuery();
        $query->columns = [ $query->columns[1] ];
        $query->orders = null;
        $count = array_get(\DB::select("select count(*) as count from ({$query->toSql()}) as haversine", $query->getBindings()), 0)->count;
    }

    return new \Illuminate\Pagination\LengthAwarePaginator(
        $builder->forPage($current_page, $per_page)->get(),
        $count, $per_page, null, compact('path')
    );
}

I haven't got any more ideas how to improve it, at least it works and i dont need to call something like

count = count($results = $builder->get());
$items = $results->forPage($curPage, $perPage);

feedback really appreciated.

Answer 1

Did you really need to create a custom paginator?

If not try to use default.

The other thing I didn't like is the raw queries, you are using a laravel so take as much advantage as you can.

You will need to show your controller action for more feedback.

To be honest stackoverflow is not really the best place for this question, code review stack exchange would me more appropriate because you code already works and you just want to improve it