Feature support - polymorphic associations

[geneeblack]

Currently polymorphic associations are not supported in the model associations

Investigate the possibility of supporting polymorphic associations via GraphQL object interfaces

Determine if this capability is necessary or edge case

potential issue-related models may not be discoverable without a table scan to determine the possible polymorphic relations, needs to be determined if this is absolutely correct, if polymorphic relations can be established 'on the fly' in the base code it may be difficult or impossible to express a concrete interface implementation that will satisfy this capability

[geneeblack]

polymorphic associations now work for output types, still investigating input types

[geneeblack]

It doesn't look like UnionType of InterfaceType can be used as inputs, according to the spec.

folkloreinc/laravel-graphql#183

So this feature would only be an option for the output types.

I'm not sure where I want to take this, maybe as an optional opt-in type generation (since it requires a table scan upon generation to determine the polymorphic class expressions) with an optional type override if automatic generation is not opted (association name would still be traversed in the association list, but if not opted and not custom typed, then it would not be expressed. (custom type option would include docs explaining how to establish the union type). Just going to let his settle in this branch until I decide how to address it since I don't believe everyone wants to do a table scan every time the schema is generated (since this could be very costly on some systems).

Note, another immediate side effect of this type is that the parent object is not able to be dereferenced when building out the include list for the query, so any references to the parent would produce n+1 queries to the parent as well as losing the ability to filter the contents of the parent when using where clauses.

[geneeblack]

this feature was included in v0.1.0 #20