Add AuthorRole to manage relationship between Author and Book.

lib/decentralised_book_index/metadata.ex

@@ -6,11 +6,11 @@ defmodule DecentralisedBookIndex.Metadata do
     resource DecentralisedBookIndex.Metadata.Book do
       define :create_book,
         action: :create,
-        args: [:title, :isbn, :description, {:optional, :book_editions_registry_id}]
+        args: [:title, :isbn, :description, :author_roles, {:optional, :book_editions_registry_id}]
 
       define :add_book_to_related_editions_registry,
         action: :add_book_to_related_editions_registry,
-        args: [:title, :isbn, :description, :related_book_id]
+        args: [:title, :isbn, :description, :author_roles, :related_book_id]
 
       define :list_books, action: :read
       define :get_book_by_id, args: [:id], action: :by_id
@@ -52,5 +52,7 @@ defmodule DecentralisedBookIndex.Metadata do
       define :update_book_editions_registry, action: :update
       define :destroy_book_editions_registry, action: :destroy
     end
+
+    resource DecentralisedBookIndex.Metadata.AuthorRole
   end
 end

lib/decentralised_book_index/metadata/author.ex

@@ -5,6 +5,7 @@ defmodule DecentralisedBookIndex.Metadata.Author do
     data_layer: AshPostgres.DataLayer
 
   require Ash.Query
+  alias DecentralisedBookIndex.Metadata
 
   postgres do
     table "authors"
@@ -87,7 +88,11 @@ defmodule DecentralisedBookIndex.Metadata.Author do
   end
 
   relationships do
-    belongs_to :author_alias_registry, DecentralisedBookIndex.Metadata.AuthorAliasRegistry do
+    belongs_to :author_alias_registry, Metadata.AuthorAliasRegistry do
+      attribute_writable? true
+    end
+
+    belongs_to :author_role, Metadata.AuthorRole do
       attribute_writable? true
     end
   end

lib/decentralised_book_index/metadata/author_role.ex

@@ -0,0 +1,49 @@
+defmodule DecentralisedBookIndex.Metadata.AuthorRole do
+  use Ash.Resource,
+    otp_app: :decentralised_book_index,
+    domain: DecentralisedBookIndex.Metadata,
+    data_layer: AshPostgres.DataLayer
+
+  alias DecentralisedBookIndex.Metadata
+
+  postgres do
+    table "author_role"
+    repo DecentralisedBookIndex.Repo
+  end
+
+  actions do
+    defaults [:read, :update, :destroy]
+
+    create :create do
+      primary? true
+      accept [:order, :role]
+      argument :author_id, :uuid
+    end
+  end
+
+  attributes do
+    uuid_primary_key :id
+
+    attribute :role, :string do
+      allow_nil? true
+      public? true
+    end
+
+    attribute :order, :integer do
+      allow_nil? false
+      public? true
+    end
+
+    timestamps()
+  end
+
+  relationships do
+    belongs_to :book, Metadata.Book do
+      allow_nil? true
+    end
+
+    has_one :author, Metadata.Author do
+      allow_nil? false
+    end
+  end
+end

lib/decentralised_book_index/metadata/book.ex

@@ -5,6 +5,7 @@ defmodule DecentralisedBookIndex.Metadata.Book do
     data_layer: AshPostgres.DataLayer
 
   require Ash.Query
+  alias DecentralisedBookIndex.Metadata
 
   postgres do
     table "books"
@@ -17,6 +18,7 @@ defmodule DecentralisedBookIndex.Metadata.Book do
     create :create do
       primary? true
       accept [:title, :isbn, :description, :book_editions_registry_id]
+      argument :author_roles, {:array, :map}
 
       change fn changeset, _ ->
         registry_id = Ash.Changeset.get_attribute(changeset, :book_editions_registry_id)
@@ -29,6 +31,8 @@ defmodule DecentralisedBookIndex.Metadata.Book do
           changeset
         end
       end
+
+      change manage_relationship(:author_roles, type: :direct_control, order_is_key: :order)
     end
 
     create :add_book_to_related_editions_registry do
@@ -38,6 +42,8 @@ defmodule DecentralisedBookIndex.Metadata.Book do
         allow_nil? false
       end
 
+      argument :author_roles, {:array, :map}
+
       change fn changeset, context ->
         related_book_id = changeset.arguments.related_book_id
 
@@ -49,6 +55,8 @@ defmodule DecentralisedBookIndex.Metadata.Book do
           Ash.Changeset.force_change_attribute(changeset, :book_editions_registry_id, related_book.book_editions_registry_id)
         end
       end
+
+      change manage_relationship(:author_roles, type: :direct_control, order_is_key: :order)
     end
 
     read :by_id do
@@ -92,6 +100,11 @@ defmodule DecentralisedBookIndex.Metadata.Book do
   end
 
   relationships do
-    belongs_to :book_editions_registry, DecentralisedBookIndex.Metadata.BookEditionsRegistry
+    belongs_to :book_editions_registry, Metadata.BookEditionsRegistry
+
+    has_many :author_roles, Metadata.AuthorRole do
+      sort order: :asc
+      public? true
+    end
   end
 end