Arbitrary number of whereHas clauses - laravel

Question

I have a product with several skus. Each sku has many attributes.
Each attribute has a type which could be something like "size" or "color", and a value, which would be something like "M", or "black".
Each product has an arbitrary number of attributes, which I've made selectable in a form.
Now, I have a list of each attribute and its value.
[
'size' => 'M',
'color' => 'black',
]
Great. Now I have to fetch the SKU(s) which correspond to these particular attributes.
For example, this works when I have just ONE attribute.
$product->skus->whereHas('attributes', function($query) {
return $query->where(['type' => 'size', 'value' => 'M']);
})->get();
But how do I build a query that returns only the skus that have attributes which match ALL of the qualifications?
And remember, these attributes are arbitrary in number. I can't hardcode it; I just have to pass the array of type-value pairs.
I figured out how to do this manually – but again it doesn't allow for the arbitrary number of attributes. Plus, it's clunky. Something like this:
$product->skus->whereHas('attributes', function($query) {
return $query->where(['type' => 'size', 'value' => 'M']);
})->whereHas('attributes', function($query) {
return $query->where(['type' => 'color', 'value' => 'white']);
})->get();
Edit: The following code appears to work but it's clunky as hell. There must be a better way to do it?
$list = $this->skus()->with('attributes');
foreach ($attrs as $type => $value) {
$list->whereHas('attributes', function ($query) use ($type, $value) {
return $query->where(['type' => $type, 'value' => $value]);
});
}
return $list->first();

Answer 1

The way that you have done it seems to be the cleanest way of doing what you asked for.
Remember that Eloquent is just an abstraction of SQL.
If your writing this in SQL, it would be something like:
select * from skus
where exists (select * from attributes where sku_id = skus.id and type = ? and value = ?)
and exists (select * from attributes where sku_id = skus.id and type = ? and value = ?)
and exists (select * from attributes where sku_id = skus.id and type = ? and value = ?)
...
This is essentially what you have already done with Eloquent in your question:
$list = $this->skus()->with('attributes');
foreach ($attrs as $type => $value) {
$list->whereHas('attributes', function ($query) use ($type, $value) {
return $query->where(['type' => $type, 'value' => $value]);
});
}
return $list->first();