Better control of relationships serialization

[grzuy]

Hi 👋

Would be great to have more control (being able to customize) how a resource relationships object is serialized.

Per the v1.1 spec https://jsonapi.org/format/#document-resource-object-relationships

A “relationship object” MUST contain at least one of the following: links, data, meta.

Being able to control the content of data, links and meta for the relationship object.

To name a few:

• Being able to render only links - no data or meta (not possible, example naive patch)
• Being able to render only data - no links or meta (technically possible, but you need to globally set add_auto_links: false which also removes pagination links and other links elsewhere)
• Able to customize which links are rendered (not possible)
  • only self
  • only related
  • both
  • other?
  • being able to customize what the links are set to instead of the defaults
• continue to have control of whether the relationship is included in included for a compound document or not (possible)
• Being able to render meta (not possible)

As of today all you can do to customize a relationship is to set :included or not in the 3rd tuple element in

defmodule PostView do
  use JSONAPI.View, type: "posts"

  def relationships do
    [comments: CommentView]
  end

defmodule PostView do
  use JSONAPI.View, type: "posts"

  def relationships do
    [comments: {CommentView, :included}]
  end

Maybe we could use this 3rd element to eventually be a more capable configuration structure? Like accept there a keyword list with configuration options?

Thanks in advance.