ash_graphql/documentation/topics/relay.md
Riccardo Binetti 66d2f44443
feat: add Relay ID translation in mutation and queries (#109)
Adds a new option for queries and mutations that defines which arguments or
attributes will use a global Relay ID and their type. This allows automatically
decoding them before hitting their action.

This paves the way to automatic translation derived from the arguments, which
will be implemented subsequently.

---------

Co-authored-by: Zach Daniel <zachary.s.daniel@gmail.com>
2024-02-06 09:46:09 -05:00

1.6 KiB

Relay

Enabling relay for a resource sets it up to follow the relay specification.

The two changes that are made currently are:

  • the type for the resource will implement the Node interface
  • pagination over that resource will behave as a Connection.

Using with Absinthe.Relay

Use the following option when calling use AshGraphql

use AshGraphql, define_relay_types?: false

Relay Global IDs

Use the following option to generate Relay Global IDs (see here).

use AshGraphql, relay_ids?: true

This allows refetching a node using the node query and passing its global ID.

Translating Relay Global IDs passed as arguments

When relay_ids?: true is passed, users of the API will have access only to the global IDs, so they will also need to use them when an ID is required as argument. You actions, though, internally use the normal IDs defined by the data layer.

To handle the translation between the two ID domains, you can use the relay_id_translations option. With this, you can define a list of arguments that will be translated from Relay global IDs to internal IDs.

For example, if you have a Post resource with an action to create a post associated with an author:

create :create do
  argument :author_id, :uuid

  # Do stuff with author_id
end

You can add this to the mutation connected to that action:

mutations do
  create :create_post, :create do
    relay_id_translations [input: [author_id: :user]]
  end
end