Add a kwarg to override relationships rendered in jsonapi errors

[Startouf]

This especially allows to render jsonapi errors without a jsonapi payload (such as GET requests) by passing relationships: {}

Features

• Pass relationships: false to send empty second argument
• relationships: Argument is optional
• Non breaking changes (default remains to send controller deserialized relationships)

[richmolj]

Thanks for this PR!

I think my preference would be relationships: false instead of relationships: {}. Would that make sense to you?

[Startouf]

I actually meant to commit nil but forgot to copy my local changes to the branch request.
You mean by passing false we should not pass any relationship argument to the call to the constructor ?

My suggestion in this case

def render_errors_for(record, relationships: nil)
      relationships = if relationships == false
        {}
      else
        relationships || deserialized_params.relationships
      end

      validation = Serializers::Validation.new(record, relationships)
end

So we need to explicitely pass relationships: false to skip relationships. Otherwise we can pass manually a relationships argument to skip using deserialized_params.relationships
(And tis is non breaking : without the relationships param we get the default deserialized_params.relationships)

[richmolj]

Having thought about this a bit more, I think your original commit was probably the way to go. I'm looking for

def render_errors_for(record, relationships: {})
# ... code ...
  relationships || deserialized_params.relationships # at some point

If we get that + a spec I'll merge 👍

[richmolj]

this would never hit the right side of || since this defaults to {}. Maybe line 6 should be nil, but you can still pass a custom hash?

[Startouf]

Hey thanks and sorry about that, I'm still working on it and the test, didn't mean to push that commit ^^"
Regarding the test, since it's quite a big integration test I need some more time to work on it