WhereHas filter issue

[X-Coder264]

I'm having some issues with the WhereHas filter.

This is the relation in my foo resource schema

BelongsToMany::make('domains')

and this is how the filter is defined

WhereHas::make($this, 'domains')

My domain resource schema has the ID filter defined -> Where::make('id')

Doing a request to my foo resource index endpoint with ?filter[domains][id]=1
throws Encountered filters that are not defined on the foo schema or domains relation: id exception (this happens in \LaravelJsonApi\Eloquent\QueryBuilder\Applicators\FilterApplicator::rejectUnrecognised)

The issue is that \LaravelJsonApi\Eloquent\QueryBuilder\Applicators\FilterApplicator::cursor does not return the relation filters at all because it calls \LaravelJsonApi\Eloquent\Fields\Relations\BelongsToMany::filters which does not yield any filters (because as far as I can see the only way to add filters is to use the withFilters method but I don't see any call to that method in the entire codebase of this package).

My current workaround is to define the relationship field as
BelongsToMany::make('domains')->withFilters(new Where('id')) // I'm manually calling withFilters here to make it work

which according to the documentation (https://laraveljsonapi.io/docs/1.0/schemas/filters.html#wherehas) shouldn't be necessary to do as it says

So in this example, the client can provide any filters that are valid for the comments resource

If I replace the \LaravelJsonApi\Eloquent\Filters\WhereHas::apply method logic from the current one to the one that was initially PR-ed in laravel-json-api/eloquent#16 then it works without having to manually call the withFilters method.

The issue is maybe related to #121

[lindyhopchris]

Thanks for reporting. I think this is a symptom of adding a feature without proper unit tests.

[X-Coder264]

@lindyhopchris I've created a PR that fixes this problem -> laravel-json-api/eloquent#22

[lindyhopchris]

@X-Coder264 thanks for submitting the PR. Having investigated, the bug is actually in the WhereHas filter. When it creates the FilterApplicator it was passing in the wrong schema. Previously it was passing in the schema to which the relationship belongs, which is wrong. My fix is to pass in the schema for the model on the inverse side of the relationship.

I.e. if you had a WhereHas filter on a PostSchema for its tags relationship. Previously it was passing the post schema to the filter applicator. The fix is to pass the relationship's inverse schema, which is the tag schema in this example.

I've pushed a branch with the fix on. It'd be great if you could give it a go before I merge and tag a fix. I've written tests that are now passing so I'm confident that I've got the fix right, but as you're actually using this filter it would be great if you could test too.

To add to your application:

composer require "laravel-json-api/eloquent:dev-feature/where-has as 1.0.1"

Think I've got that command right! Let me know if the fix works.

[X-Coder264]

@lindyhopchris Thank you for working on this. I just went away from my laptop, I'll test this in the next 3 - 5 hours and report back.

[lindyhopchris]

No problem, sorry it's just taken me a while to get to it.

Don't worry about reporting back in a hurry... I'm about to clock off for the night so won't look at this until tomorrow evening at the earliest (UK time).

[X-Coder264]

@lindyhopchris You have nothing to be sorry for, it's not like the issue has been opened for two years, it hasn't been even two weeks yet.

I tested the fix and I can confirm that the filter is now working as intended 🎉

[lindyhopchris]

@X-Coder264 great, glad to hear it's now working