Absinthe.Federation
Apollo Federation support for Absinthe
Installation
Install from Hex.pm:
def deps do
[
{:absinthe_federation, "~> 0.1.4"}
]
end
Install from github:
def deps do
[
{:absinthe_federation, github: "DivvyPayHQ/absinthe_federation", branch: "main"}
]
end
Add the following line to your absinthe schema
defmodule MyApp.MySchema do
use Absinthe.Schema
+ use Absinthe.Federation.Schema
query do
...
end
end
Usage
Macro based schemas (recommended)
defmodule MyApp.MySchema do
use Absinthe.Schema
+ use Absinthe.Federation.Schema
query do
+ extends()
field :review, :review do
arg(:id, non_null(:id))
resolve(&ReviewResolver.get_review_by_id/3)
end
...
end
object :product do
+ key_fields("upc")
+ extends()
field :upc, non_null(:string) do
+ external()
end
field(:reviews, list_of(:review)) do
resolve(&ReviewResolver.get_reviews_for_product/3)
end
+ field(:_resolve_reference, :product) do
+ resolve(&ProductResolver.get_product_by_upc/3)
+ end
end
end
SDL based schemas (experimental)
defmodule MyApp.MySchema do
use Absinthe.Schema
+ use Absinthe.Federation.Schema
import_sdl """
extend type Query {
review(id: ID!): Review
}
extend type Product @key(fields: "upc") {
upc: String! @external
reviews: [Review]
}
"""
def hydrate(_, _) do
...
end
Resolving structs in _entities queries
If you need to resolve your struct to a specific type in your schema you can implement the Absinthe.Federation.Schema.EntityUnion.Resolver
protocol like this:
defmodule MySchema do
@type t :: %__MODULE__{
id: String.t()
}
defstruct id: ""
defimpl Absinthe.Federation.Schema.EntityUnion.Resolver do
def resolve_type(_, _), do: :my_schema_object_name
end
end
More Documentation
See additional documentation, including guides, in the Absinthe.Federation hexdocs.
Contributing
Refer to the Contributing Guide.
License
See LICENSE