Craft GraphQL APIs in Elixir with Absinthe

Building the Resolver

Let’s build the resolver function. It will grab the :input argument for us, and then call a general-purpose PlateSlate.Menu.create_item/1 function that will handle attempting to persist the record:

05-chp.mutations/2-create/lib/plate_slate_web/resolvers/menu.ex

def create_item(_, %{input: params}, _) do
  case Menu.create_item(params) do 
    {:error, _} ->
      {:error, "Could not create menu item"}
    {:ok, _} = success ->
      success
  end
end

Here’s how we’ve implemented PlateSlate.Menu.create_item/1:

05-chp.mutations/2-create/lib/plate_slate/menu/menu.ex

def create_item(attrs \\ %{}) do
  %Item{}
  |> Item.changeset(attrs)
  |> Repo.insert()
end

The actual persistence of the ...