Laravel mapWithKeys() returns single value - laravel

Question

In laravel I'm getting products array that looks like this
dd($activity->load('products'));
"products": [
{
"id": 1,
"pivot": {
"activity_id": 1,
"product_id": 10,
"quantity": 16
}
},
{
"id": 2,
"pivot": {
"activity_id": 1,
"product_id": 11,
"quantity": 20
}
}
]
I want to get an array of objects and pluck only the pivot.product_id and pivot.quantity from the products array
Expected result:
"selected_products": [
{
"id": 10,
"quantity": 16
},
{
"id": 11,
"quantity": 20
}
]
What I tried
return $activity
->load('products')
->products()
->get()
->mapWithKeys(function ($product, $key) {
return ['id' => $product->pivot->product_id, 'quantity' => $product->pivot->quantity];
});
Result
{
"id": 10,
"quantity": 16
}

Answer 1

There are 2 problems on your code.
First, load('products') is redundant. You cam simple call $activity->products. Or if you need filter on the products , use $activity->products()->where(...)->get()
Second, you should use map for indexed array. mapWithKeys is using for associative array.
return $activity->products
->map(function ($product, $key) {
return ['id' => $product->pivot->product_id, 'quantity' => $product->pivot->quantity];
});